1WTNT41 KNHC 260847 2TCDAT1 3TROPICAL STORM ALEX DISCUSSION NUMBER 3 4NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 5500 AM EDT SAT JUN 26 2010 6 7AN AIR FORCE RESERVE HURRICANE HUNTER INVESTIGATING TROPICAL 8DEPRESSION ONE REPORTED 925 MB FLIGHT-LEVEL WINDS OF 46 KT ABOUT 90 9NM EAST OF THE CENTER...WHICH SUGGEST SURFACE WINDS OF NEAR 35 KT. 10THE STEPPED FREQUENCY MICROWAVE RADIOMETER ON THE AIRCRAFT SHOWED A 11LARGE AREA OF WINDS NEAR 35 KT THAT DID NOT APPEAR TO BE RAIN- 12CONTAMINATED. BASED ON THIS...THE DEPRESSION IS UPGRADED TO 13TROPICAL STORM ALEX WITH AN INITIAL INTENSITY OF 35 KT. THE 14AIRCRAFT DATA SUGGESTS THAT THE CIRCULATION OF ALEX REMAINS 15BROAD...AND THAT THE RECENTLY REPORTED CENTRAL PRESSURE OF 1004 MB 16MAY HAVE BEEN MEASURED IN A MESOSCALE LOW PRESSURE AREA. IT SHOULD 17BE NOTED THAT THE AIRCRAFT REPORTED SFMR WINDS IN EXCESS OF 40 KT 18WHICH APPEAR SUSPECT DUE TO RAIN CONTAMINATION. 19 20THE INITIAL MOTION REMAINS UNCERTAIN...WITH THE BEST ESTIMATE OF 21285/7. FOR THE NEXT 24 TO 48 HOURS ALEX IS EXPECTED TO MOVE 22WEST-NORTHWESTWARD OR NORTHWESTWARD TO THE SOUTH OF A LOW/MID-LEVEL 23RIDGE CENTERED OVER THE EASTERN UNITED STATES. AFTER THAT...THE 24LARGE-SCALE MODELS FORECAST THE RIDGE TO WEAKEN AS A DEEP-LAYER 25TROUGH MOVES INTO THE EASTERN U. S. THERE REMAINS A SIGNIFICANT 26SPREAD IN THE MODEL GUIDANCE ON HOW THIS EVOLUTION WILL AFFECT 27ALEX. THE GFS...GFS ENSEMBLE MEAN...AND THE GFDL SHOW ENOUGH OF A 28BREAK IN THE RIDGE TO STEER ALEX NORTHWARD TOWARD THE NORTHWESTERN 29GULF COAST. THE ECMWF...NOGAPS...AND UKMET SHOW THE RIDGE REMAINING 30STRONG ENOUGH TO STEER ALEX GENERALLY WESTWARD INTO NORTHEASTERN 31MEXICO. THE HWRF AND THE CANADIAN MODELS ARE BETWEEN THESE 32EXTREMES. OVERALL...THE GUIDANCE ENVELOPE HAS SHIFTED WESTWARD 33SINCE THE LAST ADVISORY...SO THE NEW FORECAST TRACK WILL BE NUDGED 34WESTWARD AS WELL. HOWEVER...THE NEW TRACK IS STILL A LITTLE TO THE 35RIGHT OF THE CENTER OF THE GUIDANCE ENVELOPE AND THE VARIOUS 36CONSENSUS MODELS. IT IS IN BEST OVERALL AGREEMENT WITH THE HWRF. 37 38THE LARGE-SCALE MODELS FORECAST ALEX TO BE NEAR OR UNDER A LARGE 39UPPER-LEVEL ANTICYCLONE THROUGH THE FORECAST PERIOD...WHICH SHOULD 40CAUSE AN ENVIRONMENT OF LIGHT VERTICAL WIND SHEAR. AS A RESULT... 41ALEX IS FORECAST TO INTENSIFY AS LONG AS IT REMAINS OVER WATER. 42THE NEW INTENSITY FORECAST CALLS FOR A 50 KT INTENSITY AS THE 43CENTER REACHES THE COAST OF BELIZE OR THE YUCATAN PENINSULA... 44FOLLOWED BY WEAKENING OVER LAND. THE GFDL...SHIPS...AND LGEM 45MODELS FORECAST ALEX TO BE A HURRICANE OVER THE GULF OF MEXICO. 46THE INTENSITY FORECAST WILL NOT YET DO THAT...BUT WILL CALL FOR 47MORE STRENGTHENING OVER THE GULF THAN THE PREVIOUS FORECAST. 48 49FORECAST POSITIONS AND MAX WINDS 50 51INITIAL 26/0900Z 16.9N 84.9W 35 KT 52 12HR VT 26/1800Z 17.4N 86.3W 45 KT 53 24HR VT 27/0600Z 18.4N 88.0W 50 KT 54 36HR VT 27/1800Z 19.4N 89.5W 35 KT...INLAND 55 48HR VT 28/0600Z 20.5N 90.5W 30 KT...OVER WATER 56 72HR VT 29/0600Z 22.5N 92.5W 35 KT 57 96HR VT 30/0600Z 24.0N 94.0W 45 KT 58120HR VT 01/0600Z 24.5N 95.5W 60 KT 59 60$$ 61FORECASTER BEVEN 62 63 64WTNT41 KNHC 261446 65TCDAT1 66TROPICAL STORM ALEX DISCUSSION NUMBER 4 67NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 681000 AM CDT SAT JUN 26 2010 69 70SATELLITE IMAGES SHOW THAT ALEX IS A LARGE CYCLONE WITH AN EXTENSIVE 71AREA OF CLOUDINESS...NUMEROUS SQUALLS IN RAINBANDS...AND A WELL 72ESTABLISHED UPPER-LEVEL OUTFLOW IN ALL QUADRANTS. HOWEVER... A 73RECENT MICROWAVE IMAGE REVEAL THAT ALEX STILL HAS A POORLY 74ORGANIZED INNER CORE. THE INITIAL INTENSITY OF 40 KNOTS IS BASED 75ON 3.0 AND 2.5 DVORAK T-NUMBERS FROM TABF AND SAB 76RESPECTIVELY...AND SURROUNDING SURFACE OBSERVATIONS. AN AIR FORCE 77PLANE IS SCHEDULED TO INVESTIGATE ALEX LATER TODAY AND WILL PROVIDE 78A BETTER ESTIMATE OF THE INTENSITY. ALTHOUGH ALEX IS EMBEDDED 79WITHIN A FAVORABLE ENVIRONMENT FOR INTENSIFICATION...THE 80STRENGTHENING WILL BE LIMITED BY THE EFFECT OF LAND PRIMARILY AS 81THE CYCLONE CROSSES THE YUCATAN PENINSULA WITHIN 12 TO 24 HOURS. 82ONCE IN THE GULF OF MEXICO...IN A COUPLE OF DAYS...THE CYCLONE 83COULD GAIN SOME STRENGTH AND ALEX IS FORECAST TO BECOME BECOME A 84HURRICANE BY THE END OF THE FORECAST PERIOD. THE OFFICIAL INTENSITY 85FORECAST IS A BLEND OF BOTH THE LGEM AND DECAY SHIPS MODELS. 86 87SINCE WE DO NOT HAVE A RELIABLE CENTER LOCATION...THE INITIAL MOTION 88CONTINUES TO BE UNCERTAIN. THE BEST ESTIMATE IS 290 DEGREES AT 9 89KNOTS. ALEX IS CURRENTLY LOCATED ON THE SOUTH SIDE OF A SUBTROPICAL 90RIDGE EXTENDING WESTWARD FROM THE BAHAMAS ACROSS THE GULF OF 91MEXICO. THIS RIDGE WILL KEEP ALEX MOVING ON THE SAME GENERAL 92WEST-NORTHWEST TRACK FOR THE NEXT 24 TO 48 HOURS. THEREAFTER...THE 93RIDGE IS FORECAST TO WEAKEN AND ALEX SHOULD DECREASE ITS FORWARD 94SPEED. HOWEVER...MOST OF THE GLOBAL MODELS SHOW THAT THE RIDGE WILL 95BE STRONG ENOUGH TO KEEP THE CYCLONE ON A GENERAL WEST-NORTHWEST 96TRACK OVER THE SOUTHERN PORTION OF THE GULF OF MEXICO. IN 97FACT...THE GFDL/HWRF PAIR WHICH PREVIOUSLY MOVED ALEX ON A MORE 98NORTHERLY COMPONENT ACROSS THE GULF HAVE SHIFTED SOUTHWARD AND ARE 99NOW SHOWING A MORE WESTERWARD TRACK LIKE MOST OF THE GLOBAL MODELS. 100 101 102FORECAST POSITIONS AND MAX WINDS 103 104INITIAL 26/1500Z 17.3N 86.1W 40 KT 105 12HR VT 27/0000Z 17.7N 87.5W 50 KT 106 24HR VT 27/1200Z 19.0N 89.1W 30 KT...INLAND 107 36HR VT 28/0000Z 20.5N 91.0W 30 KT...OVER WATER 108 48HR VT 28/1200Z 22.0N 92.5W 40 KT 109 72HR VT 29/1200Z 23.0N 94.0W 55 KT 110 96HR VT 30/1200Z 23.5N 96.0W 65 KT 111120HR VT 01/1200Z 24.0N 98.5W 25 KT...INLAND 112 113$$ 114FORECASTER AVILA 115 116 117WTNT41 KNHC 261446 118TCDAT1 119TROPICAL STORM ALEX DISCUSSION NUMBER 4 120NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 1211000 AM CDT SAT JUN 26 2010 122 123SATELLITE IMAGES SHOW THAT ALEX IS A LARGE CYCLONE WITH AN EXTENSIVE 124AREA OF CLOUDINESS...NUMEROUS SQUALLS IN RAINBANDS...AND A WELL 125ESTABLISHED UPPER-LEVEL OUTFLOW IN ALL QUADRANTS. HOWEVER... A 126RECENT MICROWAVE IMAGE REVEAL THAT ALEX STILL HAS A POORLY 127ORGANIZED INNER CORE. THE INITIAL INTENSITY OF 40 KNOTS IS BASED 128ON 3.0 AND 2.5 DVORAK T-NUMBERS FROM TABF AND SAB 129RESPECTIVELY...AND SURROUNDING SURFACE OBSERVATIONS. AN AIR FORCE 130PLANE IS SCHEDULED TO INVESTIGATE ALEX LATER TODAY AND WILL PROVIDE 131A BETTER ESTIMATE OF THE INTENSITY. ALTHOUGH ALEX IS EMBEDDED 132WITHIN A FAVORABLE ENVIRONMENT FOR INTENSIFICATION...THE 133STRENGTHENING WILL BE LIMITED BY THE EFFECT OF LAND PRIMARILY AS 134THE CYCLONE CROSSES THE YUCATAN PENINSULA WITHIN 12 TO 24 HOURS. 135ONCE IN THE GULF OF MEXICO...IN A COUPLE OF DAYS...THE CYCLONE 136COULD GAIN SOME STRENGTH AND ALEX IS FORECAST TO BECOME BECOME A 137HURRICANE BY THE END OF THE FORECAST PERIOD. THE OFFICIAL INTENSITY 138FORECAST IS A BLEND OF BOTH THE LGEM AND DECAY SHIPS MODELS. 139 140SINCE WE DO NOT HAVE A RELIABLE CENTER LOCATION...THE INITIAL MOTION 141CONTINUES TO BE UNCERTAIN. THE BEST ESTIMATE IS 290 DEGREES AT 9 142KNOTS. ALEX IS CURRENTLY LOCATED ON THE SOUTH SIDE OF A SUBTROPICAL 143RIDGE EXTENDING WESTWARD FROM THE BAHAMAS ACROSS THE GULF OF 144MEXICO. THIS RIDGE WILL KEEP ALEX MOVING ON THE SAME GENERAL 145WEST-NORTHWEST TRACK FOR THE NEXT 24 TO 48 HOURS. THEREAFTER...THE 146RIDGE IS FORECAST TO WEAKEN AND ALEX SHOULD DECREASE ITS FORWARD 147SPEED. HOWEVER...MOST OF THE GLOBAL MODELS SHOW THAT THE RIDGE WILL 148BE STRONG ENOUGH TO KEEP THE CYCLONE ON A GENERAL WEST-NORTHWEST 149TRACK OVER THE SOUTHERN PORTION OF THE GULF OF MEXICO. IN 150FACT...THE GFDL/HWRF PAIR WHICH PREVIOUSLY MOVED ALEX ON A MORE 151NORTHERLY COMPONENT ACROSS THE GULF HAVE SHIFTED SOUTHWARD AND ARE 152NOW SHOWING A MORE WESTERWARD TRACK LIKE MOST OF THE GLOBAL MODELS. 153 154 155FORECAST POSITIONS AND MAX WINDS 156 157INITIAL 26/1500Z 17.3N 86.1W 40 KT 158 12HR VT 27/0000Z 17.7N 87.5W 50 KT 159 24HR VT 27/1200Z 19.0N 89.1W 30 KT...INLAND 160 36HR VT 28/0000Z 20.5N 91.0W 30 KT...OVER WATER 161 48HR VT 28/1200Z 22.0N 92.5W 40 KT 162 72HR VT 29/1200Z 23.0N 94.0W 55 KT 163 96HR VT 30/1200Z 23.5N 96.0W 65 KT 164120HR VT 01/1200Z 24.0N 98.5W 25 KT...INLAND 165 166$$ 167FORECASTER AVILA 168 169 170WTNT41 KNHC 262033 171TCDAT1 172TROPICAL STORM ALEX DISCUSSION NUMBER 5 173NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 174400 PM CDT SAT JUN 26 2010 175 176AN AIR FORCE PLANE REACHED ALEX AND FOUND THAT THE CYCLONE WAS A 177LITTLE STRONGER...WITH A MINIMUM PRESSURE OF 996 MB AND 178FLIGHT-LEVEL WINDS OF 59 KNOTS ON THE SOUTH SIDE. THERE WERE 179SEVERAL SFMR VALUES AROUND 55 KNOTS...AND THIS IS THE VALUE USED 180FOR THE INITIAL INTENSITY. THIS INTENSITY IS ALSO IN AGREEMENT WITH 181THE LATEST T-NUMBERS WHICH REACHED 3.0 AND 3.5 ON THE DVORAK SCALE. 182THERE IS LITTLE ROOM FOR ALEX TO INTENSIFY MUCH MORE SINCE A 183PORTION OF THE CIRCULATION IS ALREADY OVER LAND. ALEX IS EXPECTED 184TO WEAKEN OVER THE YUCATAN PENINSULA...BUT ONCE IN THE GULF OF 185MEXICO IT SHOULD BEGIN TO RE-STRENGTHEN. ALEX HAS A COUPLE OF DAYS 186OVER WATER AND IN A FAVORABLE ENVIRONMENT BEFORE IT REACHES THE 187MEXICAN COAST IN AROUND 96 HOURS. 188 189THE CENTER WAS VERY DIFFICULT TO LOCATE EARLIER TODAY BUT NOW THAT 190THE STORM IS BETTER ORGANIZED AND THE HURRICANE HUNTER PLANE 191PROVIDED A GOOD FIX...THE INITIAL MOTION IS MORE RELIABLE AND IT IS 192ESTIMATED AT 280 DEGREES AT 10 KNOTS. A STRONG SUBTROPICAL RIDGE 193EXTENDING FROM THE BAHAMAS ACROSS THE GULF OF MEXICO IS EXPECTED TO 194TO KEEP ALEX ON A GENERAL WEST-TO WEST-NORTHWEST TRACK OVER THE 195SOUTHERN GULF OF MEXICO THROUGH THE FORECAST PERIOD. A DECREASE IN 196FORWARD SPEED IS ANTICIPATED WHILE ALEX IS LOCATED IN THE SOUTHERN 197GULF OF MEXICO AS THE STEERING CURRENTS WEAKEN A LITTLE BIT. THE 198CONFIDENCE IN THE FORECAST IS HIGH BECAUSE MOST OF THE DYNAMICAL 199MODELS ARE IN GOOD AGREEMENT AND HAVE SHIFTED FARTHER SOUTH JOINING 200THE RELIABLE ECMWF. 201 202 203FORECAST POSITIONS AND MAX WINDS 204 205INITIAL 26/2100Z 17.3N 87.8W 55 KT 206 12HR VT 27/0600Z 17.7N 89.2W 30 KT...INLAND 207 24HR VT 27/1800Z 19.0N 91.0W 30 KT...INLAND 208 36HR VT 28/0600Z 20.0N 92.5W 45 KT...OVER WATER 209 48HR VT 28/1800Z 20.5N 93.5W 55 KT 210 72HR VT 29/1800Z 21.5N 95.5W 65 KT 211 96HR VT 30/1800Z 22.0N 98.0W 65 KT...INLAND 212120HR VT 01/1800Z 22.0N 101.0W 20 KT...INLAND 213 214$$ 215FORECASTER AVILA 216 217 218WTNT41 KNHC 270251 219TCDAT1 220TROPICAL STORM ALEX DISCUSSION NUMBER 6 221NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 2221000 PM CDT SAT JUN 26 2010 223 224SURFACE OBSERVATIONS AND RADAR IMAGERY FROM BELIZE INDICATE THAT THE 225CENTER OF ALEX MOVED INLAND IN THE PAST COUPLE OF HOURS JUST TO THE 226NORTH OF BELIZE CITY...WHERE RECENT OBSERVATIONS SERVE AS THE BASIS 227FOR THE CENTRAL PRESSURE OF 997 MB FOR THIS ADVISORY. WHILE DEEP 228CONVECTION HAS GENERALLY DECREASED OVER THE PAST FEW HOURS...A 229RECENT BURST DEVELOPED NEAR THE CENTER AS IT MOVED INLAND. GIVEN 230THIS...THE INITIAL INTENSITY IS LOWERED ONLY TO 50 KT...IN 231AGREEMENT WITH DVORAK CI ESTIMATES FROM TAFB AND SAB AT 0000 UTC. 232NOW THAT THE CENTER IS INLAND...WEAKENING SHOULD OCCUR OVERNIGHT 233AND EARLY SUNDAY AS ALEX MOVES ACROSS THE YUCATAN PENINSULA. AFTER 234ALEX MOVES INTO THE SOUTHERN GULF OF MEXICO...CONDITIONS APPEAR 235FAVORABLE FOR STRENGTHENING OVER WARM WATERS AND IN A LOW SHEAR 236ENVIRONMENT. THE OFFICIAL INTENSITY FORECAST IS CLOSE TO THE ICON 237INTENSITY CONSENSUS THROUGH THE PERIOD. 238 239THE INITIAL MOTION ESTIMATE IS 290/10...A LITTLE TO THE RIGHT OF THE 240PREVIOUS FORECAST. MOST OF THE TRACK MODEL GUIDANCE SHOWS A 241SUBTROPICAL RIDGE PERSISTING ACROSS THE NORTHERN GULF OF MEXICO... 242AND THESE MODELS TAKE ALEX ON A WEST OR WEST-NORTHWEST TRACK OVER 243THE SOUTHERN GULF AND INTO MEXICO IN 3 OR 4 DAYS. HOWEVER...THE 244LATEST RUNS OF THE GFDL AND GFS TAKE ALEX FARTHER NORTH LATE IN THE 245PERIOD...BUT THIS APPEARS TO BE DUE TO THE DEVELOPMENT OF SPURIOUS 246VORTICITY MAXIMA IN BOTH MODELS THAT ERODE THE RIDGE NORTH OF ALEX. 247GIVEN THEIR LACK OF CONTINUITY...THE GFS AND GFDL SOLUTIONS ARE 248CONSIDERED OUTLIERS. THE NEW OFFICIAL FORECAST IS ADJUSTED ONLY A 249LITTLE TO THE RIGHT OF THE PREVIOUS PACKAGE DUE TO THE INITIAL 250POSITION AND MOTION...AND IS IN GOOD AGREEMENT WITH A BLEND OF THE 251DYNAMICAL MODELS EXCLUDING THE GFDL AND GFS. 252 253FORECAST POSITIONS AND MAX WINDS 254 255INITIAL 27/0300Z 17.7N 88.4W 50 KT 256 12HR VT 27/1200Z 18.5N 89.9W 30 KT...INLAND 257 24HR VT 28/0000Z 19.6N 91.5W 35 KT...OVER WATER 258 36HR VT 28/1200Z 20.4N 92.6W 45 KT 259 48HR VT 29/0000Z 21.0N 93.6W 55 KT 260 72HR VT 30/0000Z 22.0N 96.0W 70 KT 261 96HR VT 01/0000Z 23.0N 99.0W 55 KT...INLAND 262120HR VT 02/0000Z 23.0N 101.5W 30 KT...INLAND 263 264$$ 265FORECASTER BRENNAN 266 267 268WTNT41 KNHC 270857 269TCDAT1 270TROPICAL STORM ALEX DISCUSSION NUMBER 7 271NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 272400 AM CDT SUN JUN 27 2010 273 274RATHER THAN BECOMING DISORGANIZED AFTER MOVING INLAND...RADAR AND 275SATELLITE DATA INDICATE THAT ALEX HAS ACTUALLY BECOME MUCH BETTER 276DEFINED. AN EYE FEATURE HAS BEEN NOTED IN BELIZE RADAR DATA AND 277SATELLITE IMAGERY INDICATES THAT CLOUD TOPS HAVE COOLED 278SIGNIFICANTLY WITH A NEARLY CLOSED RING OF -80C AND COLDER TOPS 279ENCIRCLING THE RADAR CENTER. THE UPPER-LEVEL OUTFLOW PATTERN 280REMAINS IMPRESSIVE AND ADDITIONAL CONVECTIVE BANDING FEATURES HAVE 281DEVELOPED IN ALL QUADRANTS. THE RADAR AND SATELLITE DEPICTIONS OF 282ALEX LOOKS MORE LIKE A HURRICANE THAN A LOW-END TROPICAL STORM. 283 284THE MOTION ESTIMATE IS 300/10. THE SHORT TERM MOTION IS THE ONLY 285THING STRAIGHT-FORWARD ABOUT THE FORECAST TRACK. ALL OF THE MODELS 286AGREE ON AN UPPER-LEVEL LOW CURRENTLY JUST EAST OF HUDSON BAY 287CANADA TO DIG SOUTHWARD AND CARVE OUT A DEEP TROUGH OVER MUCH OF 288THE EASTERN U.S. DURING THE NEXT 5 DAYS. AS THE TROUGH AMPLIFIES 289...THE SUBTROPICAL RIDGE CURRENTLY SITUATED ACROSS FLORIDA AND THE 290NORTHERN GULF OF MEXICO ERODES IN THE 36-72 HOUR TIME FRAME LEAVING 291A LARGE WEAKNESS IN THE RIDGE OVER THE CENTRAL AND WESTERN GULF. 292THIS WEAK FLOW PATTERN IS EXPECTED TO CAUSE ALEX TO SLOW DOWN AND 293ALLOW THE CYCLONE TO GAIN SOME LATITUDE. AFTER THAT...HOWEVER...THE 294MODELS DIVERGE SIGNIFICANTLY WITH THE GFS AND CANADIAN MODELS 295TAKING ALEX NORTHWARD THROUGH THE WEAKNESS IN THE RIDGE TO THE 296TEXAS-LOUISIANA BORDER AREA...WHEREAS THE ECMWF...NOGAPS...GFDL... 297HWRF...UKMET...AND GFS-PARALLEL MODELS MOVE ALEX WESTWARD INTO 298NORTHEASTERN MEXICO. THE MAIN DIFFERENCE IN THE MODELS IS HOW THEY 299HANDLE THE MID-LATITUDE TROUGH-RIDGE PATTERN. THE GFS AND CANADIAN 300MODELS ARE MORE PROGRESSIVE AND LESS AMPLIFIED WITH THE FLOW 301PATTERN ACROSS THE NORTHERN U.S. DURING THE FORECAST PERIOD... 302WHEREAS THE OTHER MODELS PRODUCE A STRONGER...MORE HIGHLY AMPLIFIED 303...AND SLOWER PATTERN. THE CURRENT PROGRESSIVE 5-WAVE NORTHERN 304HEMISPHERIC FLOW PATTERN WOULD TEND TO FAVOR THE THE GFS-CANADIAN 305SOLUTION...BUT AT LEAST ONE MORE MODEL CYCLE WILL BE REQUIRED TO 306CONFIRM THAT TREND. THE OFFICIAL FORECAST TRACK IS TO THE RIGHT OF 307AND SLOWER THAN THE PREVIOUS ADVISORY...AND IS SIMILAR TO THE 308CONSENSUS MODEL...TVCN. NOTE...IF THE RECENT NORTHWARD SHIFT IN THE 309MODELS CONTINUES...THEN ALEX COULD REMAIN OVER WATER FOR THE NEXT 5 310DAYS RESULTING IN A VERY POWERFUL HURRICANE. 311 312BASED ON THE MUCH IMPROVED STRUCTURE OF ALEX WHILE IT IS HAS BEEN 313OVER LAND...THE INTENSITY FORECAST HAS BEEN ADJUSTED UPWARD FROM 314THE PREVIOUS ADVISORY. WITH VERTICAL SHEAR FORECAST TO BE 5 KT OR 315LESS DURING MOST OF THE FORECAST PERIOD AND SSTS OF 28C AND WARMER 316EXPECTED ALONG THE TRACK...THERE IS AT LEAST A MODERATE LIKELIHOOD 317THAT ALEX COULD BECOME A MAJOR HURRICANE. THE OFFICIAL INTENSITY 318FORECAST IS NEARLY IDENTICAL TO THE SHIPS AND DECAY-SHIPS INTENSITY 319MODELS...AND HIGHER THAN BOTH THE GFDL AND HWRF MODELS. 320 321 322FORECAST POSITIONS AND MAX WINDS 323 324INITIAL 27/0900Z 18.3N 89.4W 35 KT 325 12HR VT 27/1800Z 19.1N 90.6W 30 KT...INLAND 326 24HR VT 28/0600Z 20.2N 91.9W 40 KT...OVER WATER 327 36HR VT 28/1800Z 20.9N 92.8W 55 KT 328 48HR VT 29/0600Z 21.5N 93.6W 65 KT 329 72HR VT 30/0600Z 22.6N 95.5W 75 KT 330 96HR VT 01/0600Z 23.2N 97.4W 85 KT 331120HR VT 02/0600Z 23.5N 99.7W 30 KT...INLAND 332 333$$ 334FORECASTER STEWART 335 336 337WTNT41 KNHC 271440 338TCDAT1 339TROPICAL DEPRESSION ALEX DISCUSSION NUMBER 8 340NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 3411000 AM CDT SUN JUN 27 2010 342 343RECENT SATELLITE IMAGERY INDICATES THAT THE CONVECTIVE TOPS NEAR THE 344CENTER OF ALEX HAVE WARMED AND DECREASED IN COVERAGE OVER THE PAST 345FEW HOURS. BASED ON THESE TRENDS...AND A LACK OF ANY OBSERVATIONS 346OF STRONGER WINDS...THE INITIAL INTENSITY IS LOWERED TO 30 KT FOR 347THIS ADVISORY. 348 349THE INTENSITY FORECAST REASONING REMAINS UNCHANGED. AFTER ALEX 350EMERGES INTO THE GULF...WARM WATERS AND LOW SHEAR WILL OFFER THE 351OPPORTUNITY FOR RESTRENGTHENING. GIVEN THAT THE LOW-LEVEL 352CIRCULATION OF ALEX REMAINS WELL DEFINED...THE FORECAST CALLS FOR 353ALEX TO REGAIN TROPICAL STORM STATUS BY TONIGHT...AND FOR STEADY 354INTENSIFICATION THROUGH 72 HOURS. THE OFFICIAL FORECAST IS ABOVE 355ALL OF THE INTENSITY GUIDANCE THROUGH 48 HOURS...AND IS IN GOOD 356AGREEMENT WITH THE DECAY SHIPS MODEL BEYOND THAT TIME. NEEDLESS TO 357SAY...THE AMOUNT OF TIME THAT ALEX SPENDS OVER THE GULF WATERS WILL 358BE THE PIVOTAL FACTOR IN HOW MUCH INTENSIFICATION OCCURS. 359 360WHILE THE SHORT-TERM MOTION OF ALEX APPEARS ALMOST DUE WEST...A 361LONGER-TERM INITIAL MOTION ESTIMATE IS TOWARD THE WEST-NORTHWEST... 362295 DEGREES AT 10 KNOTS....A LITTLE TO THE LEFT OF THE PREVIOUS 363FORECAST TRACK. DURING THE FORECAST PERIOD...THE GLOBAL MODELS ARE 364IN GENERAL AGREEMENT WITH THE EVOLUTION OF THE LARGE-SCALE FLOW 365OVER NORTH AMERICA...WITH A LONGWAVE TROUGH DEVELOPING OVER THE 366EASTERN UNITED STATES IN TWO TO THREE DAYS...AND A MID- TO 367UPPER-LEVEL RIDGE DEVELOPING UPSTREAM OF THE TROUGH OVER CENTRAL 368NORTH AMERICA. HOWEVER...SUBTLE DIFFERENCES BETWEEN THE MODELS 369RESULT IN LARGE DIFFERENCES IN THE ULTIMATE TRACK OF ALEX. THE 370GFS...CANADIAN AND GFS ENSEMBLE MEAN ARE WEAKER WITH THE CENTRAL 371U.S. RIDGE IN 4 OR 5 DAYS. AS A RESULT...THESE MODELS HAVE BEEN 372PERSISTENTLY TAKING ALEX MORE POLEWARD. THE REMAINING MODELS 373SUGGEST THAT A STRONGER RIDGE NORTH OF ALEX WILL RESULT IN A MORE 374WESTWARD TURN LATE IN THE FORECAST PERIOD. THE ECMWF ENSEMBLE MEAN 375AND THE HWRF ARE ON THE NORTH SIDE OF THIS GROUP OF MODELS...BUT DO 376NOT SHOW A SHARP NORTHWARD TURN. ALL THAT BEING SAID...THE NEW 377OFFICIAL FORECAST IS ADJUSTED A LITTLE TO THE LEFT OF THE PREVIOUS 378ONE THROUGH 36 HOURS DUE TO THE INITIAL MOTION...AND BEYOND THAT 379TIME IS A LITTLE TO THE RIGHT OF THE PREVIOUS PACKAGE AND CLOSE TO 380THE TVCN MULTI-MODEL CONSENSUS. 381 382ALL OF THE MODEL UNCERTAINTY WITH THE TRACK OF ALEX OFFERS A 383REMINDER TO NOT TO FOCUS ON THE EXACT FORECAST TRACK...PARTICULARLY 384IN THE EXTENDED PART OF THE FORECAST PERIOD...WHERE AVERAGE 385FORECAST ERRORS CAN BE 200 TO 300 MILES. 386 387FORECAST POSITIONS AND MAX WINDS 388 389INITIAL 27/1500Z 18.7N 90.6W 30 KT 390 12HR VT 28/0000Z 19.6N 91.6W 35 KT...OVER WATER 391 24HR VT 28/1200Z 20.4N 92.6W 45 KT 392 36HR VT 29/0000Z 21.1N 93.4W 55 KT 393 48HR VT 29/1200Z 21.8N 94.2W 65 KT 394 72HR VT 30/1200Z 23.0N 96.0W 75 KT 395 96HR VT 01/1200Z 23.5N 98.0W 65 KT...INLAND 396120HR VT 02/1200Z 24.0N 100.5W 30 KT...INLAND 397 398$$ 399FORECASTER BRENNAN 400 401 402WTNT41 KNHC 272035 403TCDAT1 404TROPICAL DEPRESSION ALEX DISCUSSION NUMBER 9 405NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 406400 PM CDT SUN JUN 27 2010 407 408SATELLITE IMAGES SHOW THAT ALEX CONTINUES TO HAVE A LARGE AND 409WELL-DEFINED CIRCULATION WITH PLENTY OF BANDING FEATURES. NEAR THE 410CENTER...HOWEVER...CONVECTION HAS DECREASED...PROBABLY DUE TO THE 411INFLUENCE OF LAND. THE MEXICAN NAVY SURFACE STATION AT ISLA PEREZ 412RECENTLY REPORTED 30 KT WINDS...SO THE INITIAL WIND SPEED IS KEPT 413AT 30 KT. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT IS 414SCHEDULED TO INVESTIGATE ALEX THIS EVENING AFTER THE CENTER MOVES 415OFFSHORE. 416 417THE INITIAL MOTION OF ALEX IS A LITTLE SLOWER...WITH A 12-HR AVERAGE 418YIELDING AN ESTIMATE OF 300/8. THE PIVOTAL QUESTION FOR THE 419LONG-TERM FORECAST TRACK OF THE TROPICAL CYCLONE APPEARS TO HINGE 420ON THE STRENGTH OF MID-LEVEL RIDGING OVER THE NORTHERN GULF COAST. 421THE MODELS THAT SHOW A WEAKER RIDGE...SUCH AS THE CMC/GFS/HWRF... 422ALLOW THE TROPICAL CYCLONE TO TURN TOWARD THE NORTH-NORTHWEST AND 423NORTH AND APPROACH THE NORTHWESTERN GULF COAST IN SEVERAL DAYS. 424OTHER MODELS...SUCH AS THE ECMWF/UKMET/NOGAPS...HAVE A STRONGER 425RIDGE AND KEEP ALEX MOVING TO THE NORTHWEST OR WEST-NORTHWEST INTO 426MEXICO. OVERALL THE MODEL GUIDANCE HAS SHIFTED SLIGHTLY TO THE 427NORTH...AND THE OFFICIAL FORECAST IS A LITTLE TO THE RIGHT OF THE 428PREVIOUS ONE. SINCE THERE IS CONSIDERABLE MODEL SPREAD...THIS TRACK 429FORECAST IS THOUGHT TO BE OF BELOW-AVERAGE CONFIDENCE. 430 431WHILE THERE IS A LARGE DISAGREEMENT ON THE TRACK OF ALEX...THE 432GLOBAL MODELS ARE IN MUCH BETTER AGREEMENT WITH THE LARGE-SCALE 433ENVIRONMENT. THESE MODELS SHOW AN UPPER-RIDGE AXIS SITTING VERY 434NEAR THE TROPICAL CYCLONE FOR THE NEXT SEVERAL DAYS...IN A 435FAVORABLE POSITION FOR INTENSIFICATION. COMBINED WITH THE WARM 436WATERS OF THE GULF OF MEXICO...STRENGTHENING IS LIKELY...ESPECIALLY 437AFTER ALEX MOVES FARTHER AWAY FROM THE YUCATAN PENINSULA. GIVEN THE 438OVERALL ENVIRONMENTAL CONDITIONS...IT IS SURPRISING THAT THE 439GFDL/HWRF DO NOT SHOW MORE INTENSIFICATION...LEAVING THE SYSTEM AS 440A TROPICAL STORM FOR MANY DAYS. THE STATISTICAL GUIDANCE SEEMS MORE 441REASONABLE AND THE NHC FORECAST IS CLOSE TO THE SHIPS MODEL...AND 442IS NOT TOO DISSIMILAR FROM THE PREVIOUS FORECAST. 443 444FORECAST POSITIONS AND MAX WINDS 445 446INITIAL 27/2100Z 19.2N 90.9W 30 KT 447 12HR VT 28/0600Z 19.9N 91.8W 35 KT 448 24HR VT 28/1800Z 20.6N 92.6W 45 KT 449 36HR VT 29/0600Z 21.5N 93.3W 55 KT 450 48HR VT 29/1800Z 22.3N 94.2W 65 KT 451 72HR VT 30/1800Z 23.2N 96.3W 80 KT 452 96HR VT 01/1800Z 24.0N 98.5W 55 KT...INLAND 453120HR VT 02/1800Z 24.5N 100.5W 20 KT...DISSIPATING INLAND 454 455$$ 456FORECASTER BLAKE 457 458 459WTNT41 KNHC 280241 460TCDAT1 461TROPICAL STORM ALEX DISCUSSION NUMBER 10 462NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 4631000 PM CDT SUN JUN 27 2010 464 465AN AIR FORCE RESERVE UNIT AIRCRAFT HAS BEEN INVESTIGATING ALEX THIS 466EVENING AND MEASURED A MINIMUM PRESSURE OF 991 MB AND PEAK 467FLIGHT-LEVEL WINDS OF 42 KT NORTH OF THE CENTER. THE PLANE ALSO 468MEASURED PEAK SFMR WINDS OF 41 KT TO THE NORTH OF THE CENTER. 469SATELLITE IMAGES INDICATE THAT CENTRAL CONVECTION IS REFORMING... 470BANDING FEATURES ARE GRADUALLY INCREASING...AND UPPER-LEVEL OUTFLOW 471IS WELL-ESTABLISHED IN ALL QUADRANTS EXCEPT THE NORTHWEST. BASED 472UPON THE AIRCRAFT MEASUREMENTS AND THE INCREASED ORGANIZATION ON 473SATELLITE IMAGES...ALEX IS ONCE AGAIN UPGRADED TO A TROPICAL 474STORM...AND THE ADVISORY INTENSITY IS SET AT 40 KT. 475 476ALTHOUGH THE 12-HR AVERAGE INITIAL MOTION ESTIMATE IS 300/6... 477SHORTER-TERM FIXES SUGGEST THAT ALEX MAY BE MOVING EVEN SLOWER. 478DURING THE FORECAST PERIOD...GLOBAL MODELS FORECAST AN UNUSUALLY 479DEEP LONGWAVE TROUGH TO DEVELOP OVER THE NORTHEASTERN UNITED STATES 480WHICH SHOULD RESULT IN A TEMPORARY WEAKENING OF MID-LEVEL RIDGING 481ALONG THE NORTHERN GULF COAST. THE GFS/CANADIAN MODELS CONTINUE TO 482INDICATE A WEAKER VERSION OF THE MID-LEVEL RIDGE AND HENCE A MORE 483NORTHWESTERLY OR NORTH-NORTHWESTERLY MOTION...WHILE THE ECMWF/ 484UKMET/NOGAPS HAVE CONSISTENTLY PREDICTED A STRONGER RIDGE AND MOVE 485ALEX ON A MORE WEST-NORTHWESTERLY COURSE. THE OFFICIAL NEW FORECAST 486IS QUITE SIMILAR TO THE PREVIOUS ADVISORY...AND CLOSELY FOLLOWS A 487CONSENSUS OF THE DYNAMICAL MODELS THAT EXCLUDES THE GFS...SINCE THE 488LATTER MODEL APPEARS TO BE SOMEWHAT OF A NORTHERN OUTLIER AT THIS 489TIME. 490 491NOW THAT THE CENTER OF ALEX HAS EMERGED OVER THE GULF OF 492MEXICO...GLOBAL MODELS PREDICT AN ENVIRONMENT CHARACTERIZED BY 493LIGHT VERTICAL WIND SHEAR AS ALEX MOVES OVER WARM WATERS. BOTH OF 494THESE INGREDIENTS SHOULD FAVOR STEADY INTENSIFICATION 495UNTIL LANDFALL. PERHAPS THE ONE NEGATIVE FACTOR IS THE LARGE SIZE 496OF THE CIRCULATION...AS IT MAY TAKE SOME TIME FOR THE CYCLONE TO 497CONSOLIDATE FURTHER. GIVEN THE FAVORABLE LARGE-SCALE CONDITIONS... 498IT IS STILL PUZZLING THAT THE GFDL/HWRF DO NOT SHOW ALEX 499STRENGTHENING TO MORE THAN A TROPICAL STORM DURING THE NEXT SEVERAL 500DAYS. STATISTICAL GUIDANCE...ON THE OTHER HAND...CONTINUES TO 501FORECAST A STRONGER TROPICAL CYCLONE AND THE NHC INTENSITY FORECAST 502REMAINS CLOSE TO SHIPS/LGEM MODEL OUTPUT. IN ANY EVENT...IT SHOULD 503BE NOTED THAT THE SKILL OF 2 TO 3-DAY INTENSITY FORECASTS IS VERY 504LOW. 505 506FORECAST POSITIONS AND MAX WINDS 507 508INITIAL 28/0300Z 19.4N 91.3W 40 KT 509 12HR VT 28/1200Z 20.1N 92.0W 45 KT 510 24HR VT 29/0000Z 21.0N 92.7W 50 KT 511 36HR VT 29/1200Z 21.9N 93.5W 55 KT 512 48HR VT 30/0000Z 22.6N 94.6W 65 KT 513 72HR VT 01/0000Z 23.5N 96.7W 85 KT 514 96HR VT 02/0000Z 24.3N 98.8W 50 KT...INLAND 515120HR VT 03/0000Z 25.0N 101.0W 20 KT...DISSIPATING INLAND 516 517$$ 518FORECASTER KIMBERLAIN/PASCH 519 520 521WTNT41 KNHC 280851 522TCDAT1 523TROPICAL STORM ALEX DISCUSSION NUMBER 11 524NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 525400 AM CDT MON JUN 28 2010 526 527DEEP CONVECTION WITH CLOUD TOPS OF -80C TO -84C HAVE DEVELOPED NEAR 528AND AROUND THE CENTER OF ALEX DURING THE PAST FEW HOURS. AN AIR 529FORCE RESERVE UNIT AIRCRAFT AROUND 05Z FOUND THE CENTRAL PRESSURE 530TO STILL BE AROUND 991 MB...BUT FLIGHT-LEVEL WINDS HAD INCREASED TO 53151 KT...EQUAL TO ABOUT 38 AT THE SURFACE. THE AIRCRAFT ALSO 532MEASURED AN SFMR SURFACE WIND OF 41 KT IN THE NORTHERN QUADRANT ON 533ITS OUTBOUND LEG. BASED ON THIS INFORMATION AND THE MARKED INCREASE 534IN CENTRAL DEEP CONVECTION SINCE THE RECON FIX...THE INITIAL 535INTENSITY IS SET AT 45 KT. 536 537THE INITIAL MOTION ESTIMATE IS 315/05 BASED ON RECON FIX DATA. 538COMPARED TO LAST NIGHT...THE MODELS ARE IN MUCH BETTER AGREEMENT ON 539THE EVOLUTION OF THE SYNOPTIC-SCALE FLOW PATTERN ACROSS THE U.S. 540AND THE GULF OF MEXICO. IN FACT...THE 500 MB HEIGHT AND WIND FIELDS 541ARE NEARLY IDENTICAL WITH THE STRENGTH AND PLACEMENT OF THE 542DEVELOPING TROUGH-RIDGE PATTERN THROUGH 72 HOURS. DESPITE THESE 543STRIKING SIMILARITIES...HOWEVER...THERE IS STILL CONSIDERABLE 544DIVERGENCE IN THE FORECAST TRACKS...ESPECIALLY AFTER 48 HOURS. FOR 545THE NEXT 2 DAYS OR SO...THE MODELS ARE IN GENERAL AGREEMENT ON A 546SLOW NORTHWESTWARD MOTION. AFTER THAT...THE GFS...GFS-PARALLEL... 547CMC...HWRF...AND GFDL MODEL KEEP ALEX ON A NORTHWESTWARD TRACK AND 548BRING THE CYCLONE INLAND ALONG THE LOWER OR CENTRAL TEXAS COAST. IN 549CONTRAST...THE ECMWF...UKMET...AND NOGAPS MODELS TAKE ALEX WESTWARD 550INTO THE NORTHEASTERN COAST OF MEXICO...WITH THE ECMWF HAVING THE 551MOST SOUTHERN TRACK OF THOSE MODELS. HOWEVER...THE ENTIRE NHC MODEL 552SUITE HAS SHIFTED NORTH AGAIN...ALONG WITH THE ECMWF MODEL. THE 553ONLY DIFFERENCE I CAN SEE BETWEEN THE MODELS IS THAT THE THE 554ECMWF...UKMET...AND ESPECIALLY NOGAPS DEPICT ALEX AS A SMALLER AND 555WEAKER CYCLONE THAN THE OTHER MODELS ARE FORECASTING. GIVEN THAT 556ALEX IS EXPECTED TO BE A RELATIVELY LARGE HURRICANE BY 72 HOURS... 557GREATER WEIGHT WAS PLACED ON THE OTHER MODEL SOLUTIONS... WHICH HAS 558RESULTED IN A NORTHWARD SHIFT OF THE FORECAST TRACK...BUT STILL 559REMAINS SOUTH OF THE NHC CONSENSUS MODEL..TVCN. 560 561THE NORMALLY ROBUST GFDL AND HWRF MODELS ARE STILL ONLY FORECASTING 562MODEST INTENSIFICATION OF ALEX...WHICH REMAINS SOMEWHAT PERPLEXING 563GIVEN THE VERY LOW VERTICAL SHEAR ENVIRONMENT AND IMPRESSIVE 564OUTFLOW ENVIRONMENT IN WHICH ALEX IS CURRENTLY IN AND IS FORECAST 565TO REMAIN EMBEDDED IN FOR THE NEXT SEVERAL DAYS. THE CURRENT 566CENTRAL PRESSURE IS MORE TYPICAL OF SYSTEM NEARING HURRICANE 567STRENGTH. GIVEN THAT THE SHEAR IS EXPECTED TO REMAIN QUITE LOW AND 568THE ATMOSPHERE IS FORECAST TO REMAIN VERY MOIST IN THE MID-LEVELS 569...I SEE NO REASON WHY ALEX SHOULD NOT CONTINUE TO STRENGTHEN...AND 570POSSIBLY EVEN BECOME A MAJOR HURRICANE BEFORE LANDFALL. THE 571OFFICIAL INTENSITY FORECAST IS SLIGHTLY HIGHER THAN THE VERY 572RELIABLE LGEM MODEL...WHICH BRINGS ALEX UP TO 90 KT BY 72 HOURS. 573 574 575FORECAST POSITIONS AND MAX WINDS 576 577INITIAL 28/0900Z 19.7N 91.6W 45 KT 578 12HR VT 28/1800Z 20.3N 91.9W 55 KT 579 24HR VT 29/0600Z 21.4N 92.7W 65 KT 580 36HR VT 29/1800Z 22.4N 93.6W 75 KT 581 48HR VT 30/0600Z 23.3N 94.7W 85 KT 582 72HR VT 01/0600Z 24.6N 97.0W 95 KT 583 96HR VT 02/0600Z 25.6N 99.2W 40 KT...INLAND 584120HR VT 03/0600Z 26.5N 101.0W 20 KT...DISSIPATING INLAND 585 586$$ 587FORECASTER STEWART 588 589 590WTNT41 KNHC 281445 591TCDAT1 592TROPICAL STORM ALEX DISCUSSION NUMBER 12 593NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 5941000 AM CDT MON JUN 28 2010 595 596ALTHOUGH THE CLOUD PATTERN OF ALEX HAS BECOME A LITTLE DISTORTED 597THIS MORNING...THE CYCLONE HAS CONTINUED TO GRADUALLY INTENSIFY. AN 598AIR FORCE RESERVE RECONNAISSANCE PLANE FOUND PEAK FLIGHT-LEVEL 599WINDS OF 66 KT...SFMR VALUES OF 51 KT...AND A DECREASE IN PRESSURE 600TO 989 MB. THUS THE INITIAL INTENSITY IS INCREASED A BIT TO 50 KT. 601 602THE INITIAL MOTION IS 330/5...TO THE RIGHT OF PREVIOUS ESTIMATES. AN 603UPPER-LEVEL TROUGH SEEN TO THE NORTH OF THE STORM MAY BE 604CONTRIBUTING TO THE MORE POLEWARD MOTION BY CAUSING A WEAKENING OF 605THE RIDGE OVER THE GULF COAST. THIS TROUGH IS FORECAST TO LIFT OUT 606OF THE AREA IN A DAY OR SO...WHICH SHOULD ALLOW RIDGING TO BUILD 607BACK IN SLIGHTLY AND STEER ALEX MORE TOWARD THE NORTHWEST. AFTER 608THAT TIME...THE STRENGTH OF A RIDGE OVER THE CENTRAL PLAINS SHOULD 609HELP DETERMINE WHETHER THE TROPICAL CYCLONE CONTINUES A 610NORTHWESTWARD MOTION OR MAKES MORE OF A TURN TOWARD THE 611WEST-NORTHWEST. THE MODEL GUIDANCE IS IN PRETTY GOOD AGREEMENT 612THROUGH 48 HOURS...THEN HAS A BIT MORE SPREAD. THERE HAS BEEN A 613SUBTLE SHIFT NORTHWARD WITH SOME OF THE 06Z GUIDANCE...AND THE NHC 614FORECAST HAS BEEN ADJUSTED IN THAT DIRECTION. 615 616SOME NORTHWESTERLY SHEAR IS CURRENTLY AFFECTING ALEX...ALTHOUGH THIS 617HAS NOT PREVENTED THE STORM FROM SLOWLY DEEPENING. THIS SHEAR IS 618FORECAST TO ABATE BY TOMORROW AS THE UPPER-LEVEL TROUGH PULLS OUT 619OF THE GULF OF MEXICO...WHICH COULD THEN ALLOW FOR MORE SIGNIFICANT 620STRENGTHENING. THE STATISTICAL MODELS CONTINUE TO SHOW MORE 621INTENSIFICATION OF ALEX THAN THE DYNAMICAL GUIDANCE...WHICH SEEMS 622REASONABLE GIVEN THE LIKELY ENVIRONMENTAL CONDITIONS. THE NHC 623FORECAST IS CLOSE TO THE STATISTICAL MODELS AND THE PREVIOUS 624FORECAST. 625 626FORECAST POSITIONS AND MAX WINDS 627 628INITIAL 28/1500Z 20.3N 91.7W 50 KT 629 12HR VT 29/0000Z 21.1N 92.1W 55 KT 630 24HR VT 29/1200Z 22.3N 92.9W 65 KT 631 36HR VT 30/0000Z 23.5N 94.2W 75 KT 632 48HR VT 30/1200Z 24.3N 95.5W 85 KT 633 72HR VT 01/1200Z 25.5N 97.7W 80 KT...INLAND 634 96HR VT 02/1200Z 26.5N 99.5W 35 KT...INLAND 635120HR VT 03/1200Z 27.5N 101.5W 20 KT...DISSIPATING INLAND 636 637$$ 638FORECASTER BLAKE/BRENNAN 639 640 641WTNT41 KNHC 282037 642TCDAT1 643TROPICAL STORM ALEX DISCUSSION NUMBER 13 644NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 645400 PM CDT MON JUN 28 2010 646 647DATA FROM THE AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT SUGGEST 648THAT THE INTENSITY OF ALEX HAS CHANGED LITTLE OVER THE PAST FEW 649HOURS. THE LAST PRESSURE MEASURED WAS 990 MB...UP JUST A BIT FROM 650THIS MORNING. DATA FROM THE SFMR ON THE AIRCRAFT SUPPORT 651MAINTAINING THE INTENSITY AT 50 KT. ALEX IS EXPERIENCING NORTHERLY 652WIND SHEAR OF ABOUT 10 TO 15 KNOTS ACCORDING TO THE SHIPS MODEL AND 653ANALYSES FROM UW-CIMSS. THE SHEAR IN COMBINATION WITH SOME DRY AIR 654IN THE NORTHERN PART OF THE CIRCULATION HAVE LIKELY BEEN 655RESPONSIBLE FOR THE SPOTTY NATURE OF THE DEEP CONVECTION NEAR THE 656CENTER OF ALEX TODAY. ALSO...SINCE ALEX HAS BEEN SITUATED OVER THE 657SHALLOW SHELF WATERS WEST OF THE YUCATAN ALL DAY...SOME UPWELLING 658OF COOL WATER COULD BE HINDERING DEVELOPMENT FOR THE TIME BEING. 659 660ONCE THE MID TO UPPER-LEVEL TROUGH OVER THE NORTHERN GULF OF MEXICO 661MOVES AWAY FROM ALEX...THE ENVIRONMENT SHOULD BECOME MORE FAVORABLE 662FOR INTENSIFICATION AS THE SHEAR DECREASES AND ALEX MOVES TOWARD A 663WARM EDDY IN THE SOUTHWESTERN GULF. THE OFFICIAL NHC INTENSITY 664FORECAST IS SIMILAR TO THE PREVIOUS PACKAGE...AND IS CLOSE TO A 665BLEND OF THE SHIPS AND LGEM MODELS...WHICH ARE THE STRONGEST OF THE 666INTENSITY MODELS. ALSO...ALEX COULD STRENGTHEN A LITTLE MORE BEFORE 667LANDFALL BEYOND WHAT IS SHOWN IN THE 48-HOUR FORECAST...BUT NONE OF 668THE GUIDANCE SHOWS ALEX REACHING MAJOR HURRICANE INTENSITY AT THIS 669TIME. 670 671ALEX HAS MOVED LITTLE OVER THE PAST FEW HOURS...BUT THE BEST 672LONG-TERM INITIAL MOTION ESTIMATE IS TOWARD THE NORTH-NORTHWEST... 673330 DEGREES...AT 4 KNOTS. AFTER THE UPPER-LEVEL TROUGH OVER THE 674NORTHERN GULF MOVES EAST...THE GLOBAL MODELS ARE NOW IN GENERALLY 675GOOD AGREEMENT IN BUILDING A RIDGE TO THE NORTH OF ALEX. THIS 676SHOULD RESULT IN A TURN TOWARD THE NORTHWEST AND THEN TOWARD THE 677WEST-NORTHWEST OVER THE NEXT COUPLE OF DAYS...WITH AN INCREASE IN 678FORWARD SPEED. COMPARED TO YESTERDAY...THE TRACK GUIDANCE IS IN 679BETTER AGREEMENT ON THIS SCENARIO AND HAS GENERALLY TRENDED 680SOUTHWARD AND FASTER WITH THE FORWARD SPEED. ACCORDINGLY...THE 681OFFICIAL FORECAST HAS BEEN ADJUSTED TO THE LEFT AND SHOWS AN 682INCREASE IN FORWARD SPEED...BUT NOW LIES TO THE RIGHT OF MOST OF 683THE DYNAMICAL MODELS. 684 685A HURRICANE WARNING MAY BE REQUIRED FOR A PORTION OF THE HURRICANE 686WATCH AREA TONIGHT. 687 688FORECAST POSITIONS AND MAX WINDS 689 690INITIAL 28/2100Z 20.5N 91.8W 50 KT 691 12HR VT 29/0600Z 21.5N 92.4W 60 KT 692 24HR VT 29/1800Z 22.9N 93.7W 65 KT 693 36HR VT 30/0600Z 23.8N 95.1W 75 KT 694 48HR VT 30/1800Z 24.5N 96.4W 80 KT 695 72HR VT 01/1800Z 25.5N 99.5W 60 KT...INLAND 696 96HR VT 02/1800Z 26.0N 101.0W 25 KT...INLAND 697120HR VT 03/1800Z...DISSIPATED 698 699$$ 700FORECASTER BRENNAN 701 702 703WTNT41 KNHC 290248 704TCDAT1 705TROPICAL STORM ALEX DISCUSSION NUMBER 14 706NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 7071000 PM CDT MON JUN 28 2010 708 709ALTHOUGH THE SATELLITE PRESENTATION OF ALEX CONTINUES TO BE A LITTLE 710RAGGED-LOOKING...DATA FROM THE AIR FORCE HURRICANE HUNTERS INDICATE 711THAT THE STORM IS GRADUALLY STRENGTHENING. PEAK 925 MB FLIGHT-LEVEL 712WINDS WERE 68 KT AND MAXIMUM SFMR-MEASURED WINDS WERE 53 KT. 713AIRCRAFT OBSERVATIONS ALSO SHOWED THAT THE MINIMUM CENTRAL PRESSURE 714HAS DROPPED TO 985 MB...A RATHER LOW VALUE FOR A TROPICAL STORM. 715BASED ON THE WIND MEASUREMENTS...THE INITIAL INTENSITY IS SET TO 55 716KT FOR THIS ADVISORY. 717 718CENTER FIXES FROM THE RECONNAISSANCE AIRCRAFT INDICATE THAT THE 719STORM HAS DRIFTED MOSTLY NORTHWARD OVER THE PAST SEVERAL HOURS...AND 720THE INITIAL MOTION ESTIMATE IS 360/4. THIS MOTION IS BELIEVED TO 721BE TEMPORARY BECAUSE THE GLOBAL MODELS ARE FORECASTING A MID-LEVEL 722RIDGE TO BUILD TO THE NORTH OF ALEX OVER THE NEXT COUPLE OF 723DAYS...WHICH SHOULD INDUCE A GRADUAL BEND OF THE TRACK TO THE LEFT. 724THE TRACK MODEL CONSENSUS HAS SHIFTED ABOUT A HALF DEGREE TO THE 725NORTH DUE TO THE RECENT NORTHWARD MOTION...AND THE OFFICIAL 726FORECAST IS ADJUSTED SLIGHTLY NORTHWARD AS WELL. ONE SHOULD NOT 727FOCUS ON THE EXACT LANDFALL POINT...HOWEVER...SINCE THE AVERAGE 728TRACK FORECAST ERROR IN THE 48- TO 72-HOUR TIME FRAME IS 100-150 729NAUTICAL MILES. 730 731THE WESTERLY SHEAR THAT WAS AFFECTING ALEX HAS ABATED AND THE SHIPS 732MODEL DIAGNOSES A FURTHER DECREASE IN SHEAR...TO BELOW 10 KT IN 24 733HOURS. AS ALEX MOVES AWAY FROM THE SHELF WATERS NEAR THE NORTHWEST 734COAST OF THE YUCATAN...IT SHOULD PASS OVER WARMER SEA SURFACE 735TEMPERATURES DURING THE NEXT 48 HOURS OR SO...ALTHOUGH THE 736PROJECTED TRACK IS NOW A LITTLE TO THE NORTH OF A WARM EDDY OVER 737THE SOUTHWEST GULF. IT IS STILL SOMEWHAT PUZZLING THAT THE GFDL 738AND HWRF MODELS STILL DO NOT FORECAST ALEX TO BECOME A 739HURRICANE...PARTICULARLY SINCE THE CYCLONE IS APPROACHING HURRICANE 740STRENGTH AS WE SPEAK. THE OFFICIAL INTENSITY FORECAST IS CLOSE TO 741THE STATISTICAL LGEM GUIDANCE...AND IS ESSENTIALLY THE SAME AS THE 742PREVIOUS NHC FORECAST. 743 744GIVEN THE LATEST 36-HR FORECAST POINT AND THE EXTENT OF 745TROPICAL-STORM FORCE WINDS IN THE FORECAST...IT IS TIME TO UPGRADE 746THE HURRICANE WATCH FOR TO A HURRICANE WARNING FOR THE SOUTH TEXAS 747AND NORTHEAST MEXICAN COASTS. 748 749 750FORECAST POSITIONS AND MAX WINDS 751 752INITIAL 29/0300Z 21.0N 91.6W 55 KT 753 12HR VT 29/1200Z 22.2N 92.3W 65 KT 754 24HR VT 30/0000Z 23.6N 93.5W 70 KT 755 36HR VT 30/1200Z 24.5N 95.2W 75 KT 756 48HR VT 01/0000Z 25.2N 96.9W 80 KT 757 72HR VT 02/0000Z 25.7N 99.6W 45 KT...INLAND 758 96HR VT 03/0000Z 27.0N 102.0W 20 KT...INLAND 759120HR VT 04/0000Z...DISSIPATED 760 761$$ 762FORECASTER PASCH/KIMBERLAIN 763 764 765WTNT41 KNHC 290855 766TCDAT1 767TROPICAL STORM ALEX DISCUSSION NUMBER 15 768NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 769400 AM CDT TUE JUN 29 2010 770 771A 0525Z AIR FORCE RESERVE RECON FLIGHT FOUND TWO PEAK 925 MB 772FLIGHT-LEVEL WINDS OF 73 KT LOCATED ABOUT 20 AND 45 NMI NORTHEAST 773OF THE CENTER. RELIABLE SFMR SURFACE WINDS ALONG THAT LEG WERE 774AROUND 57 KT...AND THE CENTRAL PRESSURE WAS 985 MB. SINCE THAT 775RECON FLIGHT...DEEP CONVECTION IN THE EASTERN SEMICIRCLE OF THE 776SMALL DEVELOPING EYE HAS ALSO INCREASED. SATELLITE INTENSITY 777ESTIMATES AT 06Z WERE T4.0/65 KT FROM TAFB AND T3.5/55 KT FROM SAB. 778BASED ON A BLEND OF THESE DATA...THE INITIAL INTENSITY IS SET 779AT 60 KT FOR THIS ADVISORY. 780 781THE INITIAL MOTION ESTIMATE IS 340/07 BASED ON RECON AND MICROWAVE 782SATELLITE FIX POSITIONS OVER THE PAST 8 HOURS. THE LATEST MODEL 783GUIDANCE SUITE...INCLUDING THE CONSENSUS MODELS...HAS SHIFTED 784SOUTHWARD. HOWEVER...ALEX HAS SHOWN NO SIGNS OF MAKING ANY 785SIGNIFICANT WESTWARD PROGRESS LIKE THE ECMWF...NOGAPS...GFS...AND 786GFDL MODELS HAVE BEEN AND ARE STILL FORECASTING TO OCCUR. THE 787MODELS ARE CONSISTENT...HOWEVER...ON BUILDING A SUBTROPICAL RIDGE 788TO THE NORTH AND EAST OF ALEX OVER THE NEXT 3 DAYS...WHICH IS 789EXPECTED TO GRADUALLY STEER THE CYCLONE ON A WEST-NORTHWESTWARD OR 790WESTWARD TRACK WITH TIME. HOWEVER...WATER VAPOR IMAGERY INDICATES 791THE UPPER-LEVEL OUTFLOW PATTERN IS STRONGLY ELONGATED IN A 792NORTH-SOUTH ORIENTATION. THIS IS A GOOD SHORT-TERM MOTION INDICATOR 793...WHICH WOULD SUGGEST THAT ALEX SHOULD MAINTAIN ITS CURRENT 794NORTH-NORTHWESTWARD MOTION FOR ANOTHER 6-12 HOURS BEFORE TURNING 795TOWARD THE NORTHWEST. THIS MOTION VECTOR WOULD KEEP ALEX ALONG OR 796JUST OUTSIDE THE RIGHT SIDE OF THE GUIDANCE ENVELOPE. SINCE THERE 797IS NO OBVIOUS PHYSICAL JUSTIFICATION TO SHIFT THE TRACK SOUTHWARD 798AT THIS TIME...THE OFFICIAL FORECAST IS JUST AN UPDATE OF THE 799PREVIOUS TRACK AND IS WELL TO THE RIGHT OF THE MODEL CONSENSUS. 800 801MICROWAVE DATA FROM 0114Z SSMIS AND 0243Z AMSU OVERPASSES INDICATED 802A SMALL MID-LEVEL EYE FEATURE VERY NEAR THE LOW-LEVEL RECON CENTER 803POSITION. THIS INDICATES THAT ALEX HAS A NEARLY VERTICALLY ALIGNED 804INNER CORE CIRCULATION...WHICH WOULD FAVOR STEADY INTENSIFICATION 805GIVEN THE VERY CONDUCIVE UPPER-LEVEL AND OCEANIC ENVIRONMENTS THAT 806THE CYCLONE IS FORECAST TO INTERACT WITH RIGHT UP UNTIL LANDFALL IN 807ABOUT 48 HOURS. THE OFFICIAL INTENSITY FORECAST IS SIMILAR TO THE 808PREVIOUS ADVISORY AND IS A BLEND OF THE SHIPS AND LGEM MODELS. 809 810 811FORECAST POSITIONS AND MAX WINDS 812 813INITIAL 29/0900Z 21.7N 91.9W 60 KT 814 12HR VT 29/1800Z 22.8N 92.7W 65 KT 815 24HR VT 30/0600Z 24.0N 94.2W 75 KT 816 36HR VT 30/1800Z 24.8N 95.9W 80 KT 817 48HR VT 01/0600Z 25.3N 97.4W 85 KT...NEAR NE MEXICAN COAST 818 72HR VT 02/0600Z 26.0N 100.0W 35 KT...INLAND 819 96HR VT 03/0600Z 27.5N 102.5W 20 KT...DISSIPATING INLAND 820120HR VT 04/0600Z...DISSIPATED INLAND 821 822$$ 823FORECASTER STEWART 824 825 826WTNT41 KNHC 291454 827TCDAT1 828TROPICAL STORM ALEX DISCUSSION NUMBER 16 829NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 8301000 AM CDT TUE JUN 29 2010 831 832SATELLITE IMAGERY SHOWS THAT ALEX HAS A SOMEWHAT RAGGED APPEARANCE 833THIS MORNING...WITH A CONVECTIVE BURST OCCURRING JUST EAST OF THE 834CENTER AND AN APPARENT DRY SLOT WEST OF THE CENTER. AN AIR FORCE 835RESERVE HURRICANE HUNTER AIRCRAFT REPORTED 850 MB FLIGHT-LEVEL 836WINDS OF 70 KT AND SFMR WINDS OF 57 KT IN THE NORTHEAST QUADRANT... 837THE LATTER ABOUT 20 NM FROM THE CENTER. THE MINIMUM CENTRAL 838PRESSURE WAS 982 MB. BASED ON THE AIRCRAFT WINDS...THE INITIAL 839INTENSITY REMAINS 60 KT. THE CIRRUS OUTFLOW IS FAIR TO THE NORTH 840AND EAST...AND POOR ELSEWHERE. 841 842ALEX HAS TURNED LEFT AND ACCELERATED DURING THE PAST SEVERAL HOURS. 843THE 12 HR MOTION IS 325/10...AND THE SHORT-TERM MOTION MAY BE 844FASTER. RAWINSONDE DATA THIS MORNING SHOW HEIGHT RISES FROM 845850-500 MB OVER LOUISIANA AND TEXAS...INDICATING THE LOW/MID-LEVEL 846RIDGE IN THIS AREA IS STRENGTHENING AS FORECAST BY THE LARGE-SCALE 847MODELS. THE TRACK GUIDANCE IS IN GOOD AGREEMENT THAT ALEX WILL 848GRADUALLY TURN WEST-NORTHWESTWARD AND WESTWARD ON THE SOUTH SIDE OF 849THIS RIDGE AS IT STRENGTHENS FURTHER DURING THE NEXT 24-48 HR. 850INDEED...THE ECMWF AND THE NAM SUGGEST ALEX COULD TURN SOUTH OF 851WEST AFTER IT MAKES LANDFALL. THE NEW FORECAST TRACK IS SHIFTED A 852LITTLE TO THE SOUTH AND IS FASTER THAN THE PREVIOUS TRACK BASED ON 853CURRENT POSITION AND MOTION. HOWEVER...IT STILL LIES NORTH OF THE 854CONSENSUS MODELS AND THE CENTER OF THE GUIDANCE ENVELOPE. OF THE 855DYNAMICAL GUIDANCE...ONLY THE HWRF AND NOGAPS ARE CURRENTLY NORTH 856OF THE OFFICIAL FORECAST. 857 858THE CENTRAL CONVECTIVE BURST IS PRODUCING TOPS COLDER THAN 859-80C...AND THE AIRCRAFT IS REPORTING A PARTIAL EYEWALL. THESE ARE 860SIGNS THAT ALEX COULD STRENGTHEN SOON. ON THE OTHER HAND...THE 861OUTFLOW IS RESTRICTED ON THE WEST SIDE WHERE THERE IS APPARENTLY 862SOME DRY AIR ENTRAINMENT. IN ADDITION...THE GFDL...HWRF...AND GFDN 863DO NOT FORECAST SIGNIFICANT STRENGTHENING DESPITE A SEEMINGLY 864FAVORABLE LIGHT-SHEAR WARM-WATER ENVIRONMENT. THE SHIPS AND LGEM 865MODELS CONTINUE TO FORECAST ALEX TO BECOME A HURRICANE...AND THE 866NEW INTENSITY FORECAST FOLLOWS SUIT. THE NEW FORECAST IS AN UPDATE 867OF THE PREVIOUS FORECAST AND LIES AT THE UPPER EDGE OF THE 868INTENSITY GUIDANCE ENVELOPE. 869 870THE AIRCRAFT DATA SHOW THAT THE 34 KT WIND RADII HAVE EXPANDED OVER 871ALL QUADRANTS EXCEPT THE SOUTHWEST. BETWEEN THIS AND THE FASTER 872FORWARD MOTION...THERE IS NOW ABOUT 12 HOURS LESS TIME TO MAKE 873PREPARATIONS BEFORE THE ONSET OF TROPICAL-STORM FORCE WINDS IN THE 874WARNING AREA THAN COMPARED TO THE PREVIOUS FORECAST. 875 876 877FORECAST POSITIONS AND MAX WINDS 878 879INITIAL 29/1500Z 22.7N 93.1W 60 KT 880 12HR VT 30/0000Z 23.7N 94.0W 65 KT 881 24HR VT 30/1200Z 24.7N 95.5W 75 KT 882 36HR VT 01/0000Z 25.2N 97.0W 80 KT 883 48HR VT 01/1200Z 25.7N 98.7W 50 KT 884 72HR VT 02/1200Z 26.0N 101.5W 25 KT...DISSIPATING INLAND 885 96HR VT 03/1200Z...DISSIPATED 886 887$$ 888FORECASTER BEVEN 889 890 891WTNT41 KNHC 292047 892TCDAT1 893TROPICAL STORM ALEX DISCUSSION NUMBER 17 894NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 895400 PM CDT TUE JUN 29 2010 896 897AN AIR FORCE RESERVE HURRICANE HUNTER REPORTED A CENTRAL PRESSURE OF 898981 MB AT 1716 UTC...WITH 850 MB FLIGHT-LEVEL WINDS OF 68 KT AND 899SFMR WINDS NEAR 55 KT. SINCE THEN...SATELLITE IMAGERY SHOWS THAT 900ALEX IS BECOMING BETTER ORGANIZED...WITH A WELL DEFINED CURVED 901CONVECTIVE BAND WRAPPING ALL THE WAY AROUND THE CENTER. THIS 902PATTERN YIELDS SATELLITE INTENSITY ESTIMATES OF 65 KT FROM TAFB AND 903SAB. THE INITIAL INTENSITY REMAINS 60 KT FOR THIS ADVISORY...BUT 904IT IS ANTICIPATED THAT THE NEXT AIRCRAFT MISSION NEAR 0000 UTC WILL 905FIND THAT ALEX IS A HURRICANE. 906 907ALEX HAS TURNED FARTHER TO THE LEFT AND THE INITIAL MOTION IS NOW 908310/11. THERE IS LITTLE CHANGE TO THE OVERALL FORECAST 909PHILOSOPHY...AS THE TRACK GUIDANCE REMAINS IN GOOD AGREEMENT THAT 910ALEX WILL GRADUALLY TURN WEST-NORTHWESTWARD AND WESTWARD ON THE 911SOUTH SIDE OF THE STRENGTHENING LOW/MID-LEVEL RIDGE OVER THE 912SOUTHERN PLAINS AND NORTHWESTERN GULF COAST. HOWEVER...THE CYCLONE 913HAS TURNED LEFT MORE THAN PREVIOUSLY FORECAST...AND THIS REQUIRES 914THE NEW FORECAST TRACK TO BE SHIFTED SOUTHWARD FROM THE PREVIOUS 915ADVISORY. THE NEW TRACK STILL LIES TO THE NORTH OF THE CONSENSUS 916MODELS AND THE CENTER OF THE GUIDANCE ENVELOPE...AND THE ONLY 917DYNAMICAL MODEL NORTH OF THE OFFICIAL FORECAST IS THE HWRF. THUS... 918THERE IS STILL ROOM FOR SOME ADDITIONAL SOUTHWARD ADJUSTMENT IF 919NECESSARY. 920 921ALEX IS NOW IN A LOW-SHEAR ENVIRONMENT OVER WARM SEA SURFACE 922TEMPERATURES...WHICH APPEARS FAVORABLE FOR STRENGTHENING UNTIL 923LANDFALL. ON THE OTHER HAND...THE CIRRUS OUTFLOW FROM THE CENTRAL 924CONVECTION IS POOR AT THIS TIME...AND LARGE SLOTS BETWEEN THE 925CONVECTIVE BANDS SUGGEST THAT SOME DRY AIR ENTRAINMENT IS STILL 926OCCURRING. THE GFDL...GFDN...AND HWRF ARE SHOWING MORE 927INTENSIFICATION THAN EARLIER...BUT NONE OF THEM FORECAST A PEAK 928INTENSITY OF MORE THAN 80 KT. THESE MODELS ARE CLOSE TO THE 929SHIPS/LGEM MODELS AND THE PREVIOUS INTENSITY FORECAST...SO THERE IS 930NO CHANGE TO THE INTENSITY FORECAST. WHILE NOT EXPLICITLY IN THE 931FORECAST... IT IS LIKELY THAT ALEX WILL REACH A PEAK INTENSITY OF 93280-85 KT BEFORE IT MAKES LANDFALL BETWEEN THE 24 AND 36 HR FORECAST 933POINTS. 934 935FORECAST POSITIONS AND MAX WINDS 936 937INITIAL 29/2100Z 23.2N 94.0W 60 KT 938 12HR VT 30/0600Z 23.9N 95.1W 65 KT 939 24HR VT 30/1800Z 24.5N 96.5W 75 KT 940 36HR VT 01/0600Z 24.9N 98.1W 75 KT...INLAND 941 48HR VT 01/1800Z 25.2N 99.9W 40 KT...INLAND 942 72HR VT 02/1800Z 25.5N 103.0W 25 KT...DISSIPATING INLAND 943 96HR VT 03/1800Z...DISSIPATED 944 945$$ 946FORECASTER BEVEN 947 948 949WTNT41 KNHC 300233 950TCDAT1 951HURRICANE ALEX DISCUSSION NUMBER 18 952NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 9531000 PM CDT TUE JUN 29 2010 954 955ALEX HAS GRADUALLY BECOME BETTER ORGANIZED ON SATELLITE IMAGES AND 956DVORAK CLASSIFICATIONS FROM BOTH TAFB AND SAB CONTINUE TO SUPPORT A 957CURRENT INTENSITY OF 65 KT. AN AIR FORCE RESERVE UNIT HURRICANE 958HUNTER AIRCRAFT PASSED THROUGH THE CENTER ON A NORTHWEST TO 959SOUTHEAST LEG AND MEASURED A CENTRAL PRESSURE OF 973 MB BY 960DROPSONDE. THE SFMR ABOARD THE PLANE MEASURED A SURFACE WIND OF 62 961KT JUST TO THE SOUTHEAST OF THE CENTER. SOON THEREAFTER...THE 962AIRCRAFT HAD TO DEPART THE AREA DUE TO RADAR FAILURE. BASED ON THE 963SUBSTANTIAL DROP IN CENTRAL PRESSURE SINCE EARLIER TODAY AND THE 964FACT THAT HIGHER SURFACE WINDS ARE LIKELY OCCURRING IN THE 965NORTHEAST QUADRANT...ALEX IS BEING UPGRADED TO A 65-KT HURRICANE 966FOR THIS ADVISORY. VERTICAL SHEAR IS FORECAST TO REMAIN BELOW 10 967KT FOR THE NEXT 24-48 HOURS SO THE HURRICANE SHOULD REMAIN IN AN 968ENVIRONMENT CONDUCIVE FOR INTENSIFICATION UP TO LANDFALL. THE 969SHIPS RAPID INTENSIFICATION INDEX SHOWS A 33 PERCENT PROBABILITY OF 970RAPID INTENSIFICATION...I.E. A 30-KT INCREASE OVER 24 HOURS. 971HOWEVER...NONE OF THE OTHER NUMERICAL INTENSITY GUIDANCE SHOWS ALEX 972STRENGTHENING BEYOND CATEGORY ONE STATUS PRIOR TO LANDFALL. THE 973OFFICIAL INTENSITY IS VERY CLOSE TO THE LGEM GUIDANCE AND ABOUT THE 974SAME AS THAT FROM THE PREVIOUS PACKAGE. 975 976ALEX WOBBLED WESTWARD OVER THE PAST SEVERAL HOURS. AFTER SOME 977SMOOTHING...THE INITIAL MOTION ESTIMATE IS 280/8. SHORT-TERM 978FORECASTS FROM DYNAMICAL MODELS SUCH AS THE GFDL AND GFS SUGGEST 979THAT THE WESTWARD MOTION IS TEMPORARY AND THAT A WEST-NORTHWESTWARD 980TRACK SHOULD RESUME SOON. THE FLOW TO THE SOUTH OF A MID- 981TROPOSPHERIC RIDGE SHOULD STEER THE HURRICANE ON A GENERALLY 982WEST-NORTHWESTWARD COURSE ACROSS THE WESTERN GULF OF MEXICO...WITH 983ALEX REACHING THE COAST IN ABOUT 24 HOURS. BECAUSE OF THE JOG TO 984THE LEFT...THE NEW NHC FORECAST TRACK HAS BEEN SHIFTED SLIGHTLY TO 985THE SOUTH OF THE PREVIOUS ONE. IT SHOULD BE REPEATED THAT ONE 986SHOULD NOT FOCUS ON THE EXACT PREDICTED LANDFALL POINT BECAUSE OF 987TRACK FORECAST UNCERTAINTIES...AND ALSO BECAUSE THIS IS A LARGE 988TROPICAL CYCLONE. 989 990FORECAST POSITIONS AND MAX WINDS 991 992INITIAL 30/0300Z 23.1N 94.8W 65 KT 993 12HR VT 30/1200Z 23.7N 96.0W 75 KT 994 24HR VT 01/0000Z 24.2N 97.6W 80 KT 995 36HR VT 01/1200Z 24.6N 99.2W 55 KT...INLAND 996 48HR VT 02/0000Z 24.5N 101.0W 30 KT...INLAND 997 72HR VT 03/0000Z...DISSIPATED INLAND 998 999$$ 1000FORECASTER PASCH 1001 1002 1003WTNT41 KNHC 300851 1004TCDAT1 1005HURRICANE ALEX DISCUSSION NUMBER 19 1006NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 1007400 AM CDT WED JUN 30 2010 1008 1009ALEX HAS BECOME MUCH BETTER ORGANIZED THIS MORNING BASED ON 1010WELL-DEFINED BANDING FEATURES WRAPPING INTO THE CENTER AND THE 1011APPEARANCE OF A SMALL EYE IN INFRARED IMAGERY. AN AIR FORCE RESERVE 1012UNIT RECONNAISSANCE AIRCRAFT AT 0842Z MEASURED A CENTRAL PRESSURE 1013961 MB AND 850 MB FLIGHT-LEVEL WINDS OF 82 KT IN THE NORTHEAST 1014QUADRANT. THE SFMR ABOARD THE PLANE MEASURED A RELIABLE SURFACE 1015WIND OF 62 KT AND A RAIN-CONTAMINATED PEAK WIND OF 71 KT. THE 1016DVORAK INTENSITY ESTIMATE FROM BOTH TAFB AND SAB WAS T4.5/77 KT. 1017THEREFORE...THE INITIAL INTENSITY IS CONSERVATIVELY INCREASED TO 70 1018KT FOR THIS ADVISORY. 1019 1020ALEX HAS WOBBLED WEST-NORTHWESTWARD OVER THE PAST 6 HOURS...AND EVEN 1021BRIEFLY STALLED. HOWEVER...TRENDING THROUGH THE SATELLITE AND RECON 1022FIXES YIELDS AN AVERAGE MOTION OF 290/06. UPPER-AIR OBSERVATIONS AT 102300Z INDICATED MODEST 10-30 METER HEIGHT RISES FROM 700-400 MB 1024ACROSS THE GULF COAST FROM LOUISIANA TO FLORIDA...BUT ALSO TO THE 1025NORTHWEST AND WEST OF ALEX ACROSS TEXAS MEXICO TO THE WEST. THIS 1026MEANS ALEX IS EMBEDDED BETWEEN TO RIDGES AND IN A WEAKER STEERING 1027FLOW REGIME THAT NONE OF THE MODELS PICKED UP ON IN THE SHORT TERM. 1028HOWEVER...ALL OF THE GLOBAL AND REGIONAL MODELS ARE CONSISTENT ON 1029BRINGING A MID-LEVEL RIDGE FROM WESTERN NEBRASKA SOUTHEASTWARD TO 1030THE TENNESSEE VALLEY DURING THE NEXT 48 HOURS...WHICH SHOULD ACT TO 1031STEER ALEX ON WEST-NORTHWESTWARD TRACK FOR THE NEXT 24 HOURS AND 1032THEN WESTWARD ACROSS NORTHERN MEXICO AFTER THAT. THERE HAS BEEN AN 1033INTERESTING CHANGE IN THE 00Z AND 06 MODEL GUIDANCE WITH THE ECMWF 1034SHIFTING FARTHER NORTHWARD...WHICH MEANS THIS MDOEL HAS GONE FROM 1035BEING THE PERSISTENT LEFT-MOST OF THE MODELS TO THE RIGHT SIDE OF 1036THE MODEL SUITE...AND IT NOW HAS A TRACK SIMILAR TO HWRF. THE 1037OFFICIAL FORECAST TRACK HAS BEEN SHIFTED SLIGHTLY TO THE RIGHT OF 1038THE PREVIOUS TRACK BASED ON THE MORE NORTHWARD INITIAL POSITION... 1039AND REMAINS NEAR THE EXTREME RIGHT SIDE OF THE GUIDANCE ENVELOPE 1040AND NORTH OF THE MODEL CONSENSUS. 1041 1042VERTICAL SHEAR IS FORECAST TO REMAIN LIGHT UP UNTIL LANDFALL OCCURS 1043IN ABOUT 24 HOURS. GIVEN THAT ALEX IS ALSO MOVING SLOWLY OVER SOME 1044OF THE WARMEST UPPER-OCEAN HEAT CONTENT IN THAT REGION OF THE GULF 1045OF MEXICO...STEADY STRENGTHENING RIGHT UP UNTIL LANDFALL SEEMS 1046REASONABLE. HOWEVER...GIVEN THE RELATIVELY LOW CENTRAL PRESSURE 1047RECENTLY MEASURED BY THE RECON AIRCRAFT...RAPID INTENSIFICATION OF 1048AT LEAST 30 KT IN 24 HOURS IS A DISTINCT POSSIBILITY. THE OFFICIAL 1049INTENSITY FORECAST IS A BLEND OF THE LGEM AND SHIPS MODELS. 1050 1051FORECAST POSITIONS AND MAX WINDS 1052 1053INITIAL 30/0900Z 23.3N 95.1W 70 KT 1054 12HR VT 30/1800Z 23.8N 96.2W 80 KT 1055 24HR VT 01/0600Z 24.3N 97.7W 85 KT 1056 36HR VT 01/1800Z 24.5N 99.6W 35 KT...INLAND 1057 48HR VT 02/0600Z 24.4N 101.7W 20 KT...DISSIPATING INLAND 1058 72HR VT 03/0600Z...DISSIPATED INLAND 1059 1060$$ 1061FORECASTER STEWART 1062 1063 1064WTNT41 KNHC 301448 1065TCDAT1 1066HURRICANE ALEX DISCUSSION NUMBER 20 1067NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 10681000 AM CDT WED JUN 30 2010 1069 1070 1071SATELLITE PRESENTATION HAS IMPROVED THIS MORNING WITH T-NUMBERS FROM 1072TAFB AND SAB REACHING 5.0 AND 5.5 ON THE DVORAK SCALE AND THE 1073MINIMUM PRESSURE HAS BEEN OSCILLATING BETWEEN 958 MB AND 961 MB. 1074HOWEVER...BOTH FLIGHT LEVEL WINDS AND SFMR DATA SUPPORT AN 1075INITIAL INTENSITY OF ONLY 70 KNOTS AT THIS TIME. LATEST 1076RECONNAISSANCE DATA SHOW THAT THERE ARE TWO WIND MAXIMA ON THE 1077NORTHEAST QUADRANT OF THE HURRICANE AND WINDS ARE SPREAD OUT IN 1078OTHER QUADRANTS. GIVEN SUCH A LOW MINIMUM PRESSURE...THE CURRENT 1079SATELLITE PRESENTATION AND A FAVORABLE ENVIRONMENT FOR 1080INTENSIFICATION...THE WINDS SHOULD INCREASE TODAY AND ALEX COULD 1081REACH CATEGORY TWO BEFORE LANDFALL. 1082 1083FIXES FROM THE AIRCRAFT INDICATE THAT ALEX IS MOVING TOWARD THE 1084NORTHWEST OR 320 DEGREES AT 6 KNOTS. THE CURRENT WEAKNESS IN 1085THE SUBTROPICAL RIDGE TO THE NORTH OF THE CYCLONE SHOULD BE 1086REPLACED BY A RIDGE SOON. THIS FLOW PATTERN SHOULD FORCE ALEX 1087ON A MORE WESTWARD TRACK LATER TODAY AS INDICATED IN THE OFFICIAL 1088FORECAST. IN FACT...MOST OF THE DYNAMICAL GUIDANCE FORECAST A SHARP 1089TURN TO THE WEST OR EVEN SOUTH OF DUE WEST DEPENDING UPON THE 1090FORECAST STRENGTH OF THE RIDGE IN EACH MODEL. THIS TRACK SHOULD 1091BRING THE CORE OF THE HURRICANE TO THE COAST WITHIN THE WARNING 1092AREA LATE TONIGHT OR EARLY THURSDAY. HOWEVER...ALEX IS A LARGE 1093HURRICANE WITH TROPICAL STORM FORCE WINDS EXTENDING A GREAT 1094DISTANCE FROM THE CENTER. RADAR DATA SHOW THAT STRONG SQUALLS AND 1095GUSTY WINDS ARE ALREADY NEARING THE SOUTH TEXAS AND NORTHERN MEXICO 1096COASTS. 1097 1098 1099FORECAST POSITIONS AND MAX WINDS 1100 1101INITIAL 30/1500Z 23.8N 95.5W 70 KT 1102 12HR VT 01/0000Z 24.1N 96.7W 85 KT 1103 24HR VT 01/1200Z 24.5N 98.5W 45 KT...INLAND 1104 36HR VT 02/0000Z 24.5N 101.0W 25 KT...INLAND 1105 48HR VT 02/1200Z...DISSIPATED 1106 1107$$ 1108FORECASTER AVILA 1109 1110 1111WTNT41 KNHC 302036 1112TCDAT1 1113HURRICANE ALEX DISCUSSION NUMBER 21 1114NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 1115400 PM CDT WED JUN 30 2010 1116 1117AFTER A FEW HOURS OF A TRACK BETWEEN NORTH-NORTHWEST AND NORTHWEST 1118EARLIER TODAY...AIRCRAFT...SATELLITE AND RADAR FIXES INDICATE THAT 1119ALEX HAS TURNED BACK TO THE WEST AT AN AVERAGE SPEED OF ABOUT 11 1120KNOTS. THE RIDGE THAT WAS ANTICIPATED TO BUILD NORTH OF THE 1121HURRICANE HAS MATERIALIZED AND IS NOW FORCING ALEX TO TAKE A LEFT 1122TURN DIRECTLY TOWARD THE COAST OF MEXICO. THE RIDGE IS FORECAST TO 1123PERSIST AND ALEX SHOULD MAINTAIN THIS GENERAL WESTWARD TRACK FOR 1124THE NEXT DAY OR TWO UNTIL DISSIPATION OVER MEXICO. 1125 1126ALEX IS A LARGE HURRICANE AND BOTH HURRICANE AND TROPICAL STORM 1127FORCE WINDS EXTEND A GREAT DISTANCE FROM THE CENTER. ONLY A SMALL 1128DEVIATION TO THE NORTH OF THE TRACK...LIKE THE ONE THAT OCCURRED 1129THIS MORNING...WILL BRING HURRICANE FORCE WINDS TO THE SOUTHERN 1130TEXAS COAST. THEREFORE...WE WOULD RATHER KEEP THE HURRICANE 1131WARNINGS FOR THIS PORTION OF THE TEXAS COAST AT THIS TIME. 1132 1133SATELLITE IMAGES AND DATA FROM THE HURRICANE HUNTER AIRCRAFT 1134INDICATE THAT ALEX IS BETTER ORGANIZED...AND THAT THE 1135WINDS HAVE INCREASED. THE MAXIMUM FLIGHT LEVEL WINDS REPORTED SO FAR 1136ARE 96 KNOTS AND SFMR REPORTED 81 KNOTS TO THE NORTHWEST OF THE 1137CENTER. IN ADDITION...THE EYE HAS BECOME DISTINCT ON VISIBLE IMAGES 1138AND IS SURROUNDED BY A CIRCULAR AREA OF DEEP CONVECTION. BASED ON 1139THESE DATA...THE INITIAL INTENSITY HAS BEEN INCREASED TO 80 KNOTS. 1140ENVIRONMENTAL CONDITIONS COULD ALLOW ALEX TO BECOME A CATEGORY TWO 1141HURRICANE BEFORE LANDFALL. 1142 1143 1144FORECAST POSITIONS AND MAX WINDS 1145 1146INITIAL 30/2100Z 24.5N 96.8W 80 KT 1147 12HR VT 01/0600Z 24.5N 98.0W 60 KT...INLAND 1148 24HR VT 01/1800Z 24.5N 100.0W 30 KT...INLAND 1149 36HR VT 02/0600Z 24.5N 102.5W 25 KT...DISSIPATING INLAND 1150 48HR VT 02/1800Z...DISSIPATED 1151 1152$$ 1153FORECASTER AVILA 1154 1155 1156WTNT41 KNHC 010239 1157TCDAT1 1158HURRICANE ALEX DISCUSSION NUMBER 22 1159NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 11601000 PM CDT WED JUN 30 2010 1161 1162OBSERVATIONS FROM THE BROWNSVILLE WSR-88D RADAR AND THE AIR FORCE 1163RESERVE UNIT HURRICANE HUNTERS INDICATE THAT THE EYE OF ALEX 1164CROSSED THE COAST IN A SPARSELY-POPULATED AREA OF NORTHEASTERN 1165MEXICO AROUND 0200 UTC. JUST BEFORE LANDFALL...THE AIRCRAFT 1166MEASURED SURFACE WINDS OF 87 KT FROM THE SFMR INSTRUMENT AND A 1167MINIMUM CENTRAL PRESSURE OF 947 MB. ASSUMING THAT THE PEAK WINDS 1168WERE NOT SAMPLED...AND OUT OF RESPECT FOR THE CONTINUED DROP IN 1169CENTRAL PRESSURE...THE LANDFALL INTENSITY WAS SET AT 90 KT. THE 1170CURRENT INTENSITY ESTIMATE OF 85 KT IS BASED ON AN ASSUMED SLIGHT 1171DECREASE SINCE LANDFALL. CONTINUED WEAKENING WILL OCCUR AS ALEX 1172MOVES OVER LAND...AND THE WEAKENING IS LIKELY TO BE RATHER RAPID 1173AFTER THE TROPICAL CYCLONE REACHES THE VERY HIGH AND RUGGED TERRAIN 1174ASSOCIATED WITH THE SIERRA MADRE ORIENTAL MOUNTAINS OF MEXICO. 1175DISSIPATION IS LIKELY WITHIN 36 TO 48 HOURS...IF NOT SOONER. 1176 1177INITIAL MOTION IS ABOUT 260/9...JUST A TAD SOUTH OF DUE WEST. 1178MID-LEVEL RIDGING TO THE NORTH OF ALEX IS PREDICTED TO BE MORE OR 1179LESS MAINTAINED FOR THE NEXT 24 TO 48 HOURS. THIS WOULD MOVE THE 1180CYCLONE ON A MAINLY WESTWARD TRACK UNTIL DISSIPATION. 1181 1182AS THE WINDS DECREASE AND THE SURGE AND WAVES ALONG THE COAST 1183GRADUALLY DIMINISH...THE PRIMARY THREAT FROM ALEX WILL BE 1184TORRENTIAL RAINS TOTALING AS HIGH AS 20 INCHES...WHICH WOULD LIKELY 1185PRODUCE LIFE-THREATENING FLASH FLOODS AND MUD SLIDES OVER THE 1186MOUNTAINOUS REGIONS OF MEXICO. ALSO...A FEW TORNADOES ARE POSSIBLE 1187OVERNIGHT WITHIN THE NORTHERN PORTION OF THE CIRCULATION OF ALEX. 1188 1189IT MAY BE OF INTEREST THAT ALEX WAS THE FIRST CATEGORY TWO...AND THE 1190STRONGEST...HURRICANE TO OCCUR IN JUNE SINCE ALMA OF 1966. 1191 1192FORECAST POSITIONS AND MAX WINDS 1193 1194INITIAL 01/0300Z 24.3N 97.8W 85 KT 1195 12HR VT 01/1200Z 24.3N 99.4W 60 KT...INLAND 1196 24HR VT 02/0000Z 24.3N 101.6W 30 KT...INLAND 1197 36HR VT 02/1200Z 24.8N 103.8W 20 KT...INLAND 1198 48HR VT 03/0000Z...DISSIPATED INLAND 1199 1200$$ 1201FORECASTER PASCH/BERG 1202 1203 1204WTNT41 KNHC 010836 1205TCDAT1 1206HURRICANE ALEX DISCUSSION NUMBER 23 1207NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 1208400 AM CDT THU JUL 01 2010 1209 1210ALEX IS STILL MAINTAINING DEEP CONVECTION NEAR THE CENTER AND IN A 1211LARGE CURVED RAINBAND ALONG THE COAST OF MEXICO. HOWEVER... 1212SATELLITE IMAGERY AND DATA FROM THE BROWNSVILLE DOPPLER RADAR 1213SUGGEST THAT ALEX HAS WEAKENED...WITH THE EYE BECOMING LESS 1214DISTINCT AND THE CONVECTIVE TOPS WARMING AND BECOMING LESS SYMMETRIC 1215AND OVER THE PAST FEW HOURS. THE INITIAL INTENSITY IS LOWERED 1216TO 70 KT FOR THIS ADVISORY...AND ALEX WILL CONTINUE WEAKENING AS IT 1217MOVES FARTHER INLAND. THE LOW-LEVEL CENTER WILL LIKELY DISSIPATE IN 1218THE NEXT 24 TO 36 HOURS AS IT MOVES INTO THE SIERRA MADRE ORIENTAL 1219MOUNTAINS. 1220 1221THE INITIAL MOTION ESTIMATE IS A LITTLE SOUTH OF DUE WEST...260/10. 1222A STRENGTHENING MID- AND UPPER-LEVEL RIDGE OVER THE CENTRAL UNITED 1223STATES WILL CONTINUE TO STEER ALEX GENERALLY WESTWARD UNTIL 1224DISSIPATION. BEYOND THAT TIME...MOST OF THE GLOBAL MODELS SHOW THE 1225MID-LEVEL REMNANTS OF ALEX SPLITTING...WITH ONE PART MOVING 1226WESTWARD ACROSS CENTRAL MEXICO...AND ANOTHER PORTION RECURVING 1227NORTHWARD INTO NORTHERN MEXICO AND THE SOUTHERN PLAINS OF THE U.S. 1228AHEAD OF AN AMPLIFYING MID-LATITUDE TROUGH. THESE REMNANTS...ALONG 1229WITH AN ACCOMPANYING SURGE OF MOISTURE...WILL LIKELY MAINTAIN A 1230HEAVY RAINFALL THREAT IN NORTHERN MEXICO AND PORTIONS OF THE SOUTH- 1231CENTRAL U.S. AFTER THE SURFACE CENTER OF ALEX DISSIPATES. 1232 1233FORECAST POSITIONS AND MAX WINDS 1234 1235INITIAL 01/0900Z 24.0N 99.0W 70 KT 1236 12HR VT 01/1800Z 23.9N 100.5W 40 KT...INLAND 1237 24HR VT 02/0600Z 24.1N 102.7W 25 KT...INLAND 1238 36HR VT 02/1800Z...DISSIPATED 1239 1240$$ 1241FORECASTER BRENNAN 1242 1243 1244WTNT41 KNHC 011431 1245TCDAT1 1246TROPICAL STORM ALEX DISCUSSION NUMBER 24 1247NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 12481000 AM CDT THU JUL 01 2010 1249 1250INFRARED SATELLITE SHOWS THAT CLOUD TOPS CONTINUE TO WARM NEAR THE 1251CENTER OF ALEX. THE INITIAL INTENSITY IS LOWERED TO 45 KT FOR THIS 1252ADVISORY...AND ALEX SHOULD CONTINUE TO WEAKEN TODAY. THE LOW-LEVEL 1253CENTER WILL LIKELY DISSIPATE OVERNIGHT DUE TO THE HIGH TERRAIN OF 1254MEXICO. 1255 1256THE INITIAL MOTION ESTIMATE REMAINS SOUTH OF DUE WEST...260/11. 1257A GENERAL WESTWARD TRACK IS LIKELY UNTIL DISSIPATION OVERNIGHT... 1258THEN THE REMNANTS OF ALEX SHOULD MOVE TO THE WEST OR WEST- 1259NORTHWEST. THIS SYSTEM...ALONG WITH AN ACCOMPANYING SURGE OF 1260MOISTURE...WILL LIKELY KEEP A HEAVY RAINFALL THREAT IN NORTHERN 1261MEXICO AND PORTIONS OF THE FAR SOUTH-CENTRAL U.S. FOR THE NEXT FEW 1262DAYS. 1263 1264 1265FORECAST POSITIONS AND MAX WINDS 1266 1267INITIAL 01/1500Z 23.1N 100.3W 45 KT...INLAND 1268 12HR VT 02/0000Z 23.0N 102.0W 30 KT...INLAND 1269 24HR VT 02/1200Z...DISSIPATED 1270 1271$$ 1272FORECASTER BLAKE 1273 1274 1275WTNT41 KNHC 012033 1276TCDAT1 1277TROPICAL STORM ALEX DISCUSSION NUMBER 25 1278NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 1279400 PM CDT THU JUL 01 2010 1280 1281THE LATEST SATELLITE PICTURES SHOW THAT ALEX HAS BECOME SOMEWHAT 1282RAGGED WITH WARMING CLOUD TOPS NEAR THE CENTER. IN ADDITION... 1283THE LOW- AND UPPER-LEVEL CENTERS OF ALEX HAVE DECOUPLED WITH THE 1284UPPER-LEVEL CENTER MOVING SOUTHWEST AND THE LOWER-LEVEL CIRCULATION 1285FARTHER TO THE NORTH. ZACATECAS RECENTLY REPORTED SUSTAINED 1286TROPICAL-STORM-FORCE WINDS...SO ALEX WILL STAY A 35-KT TROPICAL 1287STORM FOR THIS ADVISORY. ALEX WILL FURTHER WEAKEN...THEN PROBABLY 1288DISSIPATE OVERNIGHT DUE TO THE HIGH TERRAIN OF MEXICO. 1289 1290THE INITIAL MOTION ESTIMATE IS 270/11. THIS GENERAL TRACK IS LIKELY 1291UNTIL DISSIPATION OVERNIGHT. HOWEVER...THIS SYSTEM HAS A LARGE 1292AREA OF MOISTURE ASSOCIATED WITH IT AND THE REMNANTS OF ALEX ARE 1293EXPECTED TO KEEP A HEAVY RAINFALL THREAT IN NORTHERN MEXICO AND 1294PORTIONS OF THE FAR SOUTH-CENTRAL U.S. FOR THE NEXT FEW DAYS. 1295 1296 1297FORECAST POSITIONS AND MAX WINDS 1298 1299INITIAL 01/2100Z 23.2N 101.2W 35 KT...INLAND 1300 12HR VT 02/0600Z 23.5N 102.9W 25 KT...DISSIPATING INLAND 1301 24HR VT 02/1800Z...DISSIPATED 1302 1303$$ 1304FORECASTER BLAKE 1305 1306 1307WTNT41 KNHC 020233 1308TCDAT1 1309TROPICAL DEPRESSION ALEX DISCUSSION NUMBER 26 1310NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL012010 13111000 PM CDT THU JUL 01 2010 1312 1313ALEX HAS MOVED OVER THE RUGGED TERRAIN OF CENTRAL MEXICO AT 1314ELEVATIONS BETWEEN 5000 AND 8000 FEET...AND SATELLITE IMAGERY AND 1315SURFACE OBSERVATIONS SUGGEST THAT A WELL-DEFINED CENTER OF 1316CIRCULATION NO LONGER EXISTS. IN ADDITION...THE ONLY DEEP 1317CONVECTION LEFT IN THE VICINITY OF ALEX IS ASSOCIATED WITH UPSLOPE 1318FLOW WELL TO THE EAST ALONG THE SIERRA MADRE ORIENTAL MOUNTAINS. 1319ALEX HAS THEREFORE DISSIPATED...AND THIS WILL BE THE LAST ADVISORY 1320ON THIS SYSTEM. MAXIMUM SUSTAINED WINDS ARE ESTIMATED TO BE AROUND 132125 KT...BASED ON THE LATEST OBSERVATION AT ZACATECAS MEXICO. 1322 1323MOISTURE ASSOCIATED WITH THE REMNANTS OF ALEX WILL CONTINUE TO POSE 1324A HEAVY RAINFALL THREAT OVER PORTIONS OF NORTHERN AND CENTRAL 1325MEXICO...AS WELL AS THE SOUTHERN PLAINS OF THE UNITED STATES...OVER 1326THE NEXT FEW DAYS. FOR THE UNITED STATES...PLEASE REFER TO 1327PRODUCTS ISSUED BY THE HYDROMETEOROLOGICAL PREDICTION CENTER AND 1328LOCAL NATIONAL WEATHER SERVICE FORECAST OFFICES FOR ADDITIONAL 1329INFORMATION. 1330 1331FORECAST POSITIONS AND MAX WINDS 1332 1333INITIAL 02/0300Z 23.3N 102.4W 25 KT...POST-TROP/REMNT LOW 1334 12HR VT 02/1200Z...DISSIPATED 1335 1336$$ 1337FORECASTER BERG 1338 1339 1340