1WTNT43 KNHC 142052 2TCDAT3 3TROPICAL STORM KARL DISCUSSION NUMBER 1 4NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 5500 PM EDT TUE SEP 14 2010 6 7AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING THE LOW 8PRESSURE AREA IN THE NORTHWESTERN CARIBBEAN SEA FOUND A SMALL AND 9VIGOROUS WIND/PRESSURE CENTER INSIDE THE LARGER CYCLONIC ENVELOPE. 10THE MAXIMUM FLIGHT-LEVEL WINDS WERE 41 KT AT LESS THAN 1500 FT JUST 11EAST OF THE CENTER...AND THE SFMR ESTIMATED RELIABLE-LOOKING WINDS 12OF 35 KT OUTSIDE OF THE HEAVY RAIN AREAS. THE MINIMUM CENTRAL 13PRESSURE WAS 1001 MB. BASED ON THESE DATA...THE SYSTEM IS UPGRADED 14STRAIGHT TO TROPICAL STORM KARL WITH AN INITIAL INTENSITY OF 35 KT. 15 16THE INITIAL MOTION IS 295/13. KARL IS LOCATED ON THE SOUTH SIDE OF 17A DEEP-LAYER RIDGE CENTERED ALONG THE NORTHERN GULF COAST. THE 18TRACK GUIDANCE IS IN GOOD AGREEMENT THAT THE RIDGE SHOULD STEER 19KARL GENERALLY WEST-NORTHWESTWARD ACROSS THE YUCATAN PENINSULA INTO 20THE SOUTHWESTERN GULF OF MEXICO...FOLLOWED BY A GENERAL WESTWARD 21MOTION TOWARD MAINLAND MEXICO. THERE IS SOME SPREAD IN THE TRACK 22GUIDANCE OVER THE GULF OF MEXICO...WITH SOME OF THE DYNAMICAL 23MODELS FORECASTING A SOUTH-OF-WEST MOTION BEFORE KARL REACHES THE 24COAST OF MAINLAND MEXICO. THE FORECAST TRACK WILL SHOW A WESTWARD 25MOTION AFTER 72 HR...AND OVERALL IT LIES DOWN THE CENTER OF THE 26GUIDANCE ENVELOPE. 27 28KARL IS IN AN ENVIRONMENT OF LIGHT EASTERLY VERTICAL WIND SHEAR... 29AND THIS IS FORECAST TO PERSIST FOR THE NEXT 4-5 DAYS. THE MAJOR 30INFLUENCE ON THE INTENSITY WILL BE LAND INTERACTION. WHILE THE 31INTENSITY FORECAST SHOWS KARL WITH 45-KT WINDS OVER EASTERN 32YUCATAN...THE STORM COULD REACH A HIGHER INTENSITY BETWEEN THE 12 33AND 24 HR FORECAST POINTS. OVER THE GULF OF MEXICO...KARL SHOULD 34RE-INTENSIFY...WITH THE SHIPS AND GFDL MODELS CALLING FOR IT TO 35BECOME A HURRICANE. THE INTENSITY FORECAST IS A BIT MORE 36CONSERVATIVE DUE TO UNCERTAINTY ABOUT WHAT KIND OF STRUCTURE KARL 37WILL HAVE AFTER CROSSING THE YUCATAN PENINSULA. AFTER FINAL 38LANDFALL IN MEXICO...KARL SHOULD EVENTUALLY DISSIPATE OVER THE 39MOUNTAINS OF CENTRAL MEXICO. 40 41 42FORECAST POSITIONS AND MAX WINDS 43 44INITIAL 14/2100Z 18.3N 84.2W 35 KT 45 12HR VT 15/0600Z 18.9N 86.0W 40 KT 46 24HR VT 15/1800Z 19.6N 88.1W 45 KT...INLAND 47 36HR VT 16/0600Z 20.4N 90.3W 30 KT...INLAND 48 48HR VT 16/1800Z 21.0N 92.6W 35 KT...OVER WATER 49 72HR VT 17/1800Z 21.5N 96.0W 55 KT 50 96HR VT 18/1800Z 21.5N 99.5W 30 KT...INLAND 51120HR VT 19/1800Z...DISSIPATED 52 53$$ 54FORECASTER BEVEN 55 56 57WTNT43 KNHC 150243 58TCDAT3 59TROPICAL STORM KARL DISCUSSION NUMBER 2 60NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 611000 PM CDT TUE SEP 14 2010 62 63THE AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING KARL 64EARLIER THIS EVENING FOUND PEAK 925 MB FLIGHT-LEVEL WINDS OF 49 KT 65AND SEVERAL BELIEVABLE 34-39 KT SFMR SURFACE WINDS JUST NORTH OF 66THE CENTER AS IT EXITED THE STORM. THESE DATA WERE THE BASIS FOR 67THE INCREASE IN INTENSITY IN THE 0000 UTC INTERMEDIATE ADVISORY. 68THE ORGANIZATION OF THE CYCLONE HAS CHANGED LITTLE SINCE THAT 69TIME...THEREFORE THE INITIAL INTENSITY REMAINS 40 KT. THE NEXT AIR 70FORCE RESERVE RECONNAISSANCE MISSION IS SCHEDULED TO REACH KARL 71AROUND 0600 UTC. 72 73THE AIRCRAFT FIXES AND A COUPLE OF RECENT SSMIS MICROWAVE IMAGES 74SHOW THAT THE CENTER IS LOCATED NEAR THE EASTERN EDGE OF THE SMALL 75MASS OF DEEP CONVECTION...WHICH SUGGESTS THAT THERE IS SOME LIGHT 76EASTERLY SHEAR. THE SHEAR...HOWEVER...IS NOT EXPECTED TO BE 77INHIBITIVE FOR STRENGTHENING...AND SOME INTENSIFICATION IS POSSIBLE 78BEFORE KARL REACHES THE EAST COAST OF THE YUCATAN PENINSULA. OVER 79THE SOUTHWESTERN GULF OF MEXICO...WATERS ARE WARM AND THE SHEAR IS 80EXPECTED TO BE LIGHT...THEREFORE STRENGTHENING IS EXPECTED. THE 81GFDL...LGEM...SHIPS...AND FLORIDA STATE SUPERENSEMBLE ALL SHOW KARL 82AT HURRICANE STRENGTH BEFORE IT REACHES THE COAST OF MAINLAND 83MEXICO IN ABOUT 72 HOURS. THERE IS STILL SOME UNCERTAINTY ABOUT 84WHAT KIND OF STRUCTURE KARL WILL HAVE AFTER CROSSING THE YUCATAN 85PENINSULA...HOWEVER GIVEN THE FAVORABLE CONDITIONS AND MODEL 86AGREEMENT...THE OFFICIAL FORECAST BRINGS KARL TO HURRICANE STATUS 87AT THAT TIME. 88 89THE INITIAL MOTION IS 290/13. THE TRACK FORECAST PHILOSOPHY REMAINS 90UNCHANGED. KARL IS EXPECTED TO MOVE GENERALLY WEST-NORTHWESTWARD 91AROUND THE SOUTHERN PORTION OF A DEEP-LAYER RIDGE ALONG THE 92NORTHERN GULF COAST. THE TRACK GUIDANCE IS IN GOOD AGREEMENT 93THROUGH 48 HOURS...WITH INCREASED SPREAD THEREAFTER...AS SOME OF THE 94MODELS TURN KARL WEST-SOUTHWESTWARD NEAR THE COAST OF MAINLAND 95MEXICO. THE NEW NHC TRACK IS ESSENTIALLY AN UPDATE OF THE PREVIOUS 96ADVISORY AND IS IN GOOD AGREEMENT WITH THE GFS AND ECMWF MODELS. 97 98FORECAST POSITIONS AND MAX WINDS 99 100INITIAL 15/0300Z 18.6N 85.5W 40 KT 101 12HR VT 15/1200Z 19.2N 87.3W 50 KT 102 24HR VT 16/0000Z 20.0N 89.5W 30 KT...INLAND 103 36HR VT 16/1200Z 20.7N 91.6W 35 KT 104 48HR VT 17/0000Z 21.1N 93.4W 50 KT 105 72HR VT 18/0000Z 21.5N 96.7W 65 KT 106 96HR VT 19/0000Z 21.5N 100.5W 25 KT...INLAND 107120HR VT 20/0000Z...DISSIPATED 108 109$$ 110FORECASTER BROWN 111 112 113WTNT43 KNHC 150840 114TCDAT3 115TROPICAL STORM KARL DISCUSSION NUMBER 3 116NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 117400 AM CDT WED SEP 15 2010 118 119THE AIR FORCE RESERVE HURRICANE HUNTERS INVESTIGATING KARL EARLY 120THIS MORNING FOUND THAT THE STORM HAS STRENGTHENED SOMEWHAT SINCE 121THE LAST RECONNAISSANCE MISSION ON TUESDAY AFTERNOON. THE CENTRAL 122PRESSURE HAS FALLEN TO 995 MB AND THE MAXIMUM UNCONTAMINATED 123SFMR-OBSERVED SURFACE WIND VELOCITIES WERE ABOUT 55 KT...WHICH IS 124THE VALUE USED FOR THE CURRENT ADVISORY INTENSITY. SATELLITE 125IMAGES SHOW THAT A RATHER SYMMETRICAL UPPER-LEVEL OUTFLOW PATTERN 126IS DEVELOPING OVER KARL...SO SOME ADDITIONAL INTENSIFICATION COULD 127OCCUR BEFORE LANDFALL. FORTUNATELY...THE TIME IS SHORT BEFORE THE 128CENTER SHOULD CROSS THE COAST. 129 130KARL WOBBLED WESTWARD A FEW HOURS AGO BUT THE LATEST AIRCRAFT FIXES 131INDICATE THAT A WEST-NORTHWESTWARD MOTION...AROUND 285/11...HAS 132RESUMED. BASED ON GLOBAL MODEL FORECASTS...A MID-TROPOSPHERIC 133RIDGE SHOULD REMAIN IN PLACE TO THE NORTH OF THE TROPICAL CYCLONE 134FOR THE NEXT 2 TO 3 DAYS. THEREFORE A WEST-NORTHWESTWARD TO 135WESTWARD TRACK APPEARS LIKELY...WHICH WOULD TAKE THE CENTER ACROSS 136THE NORTHEASTERN COAST OF MAINLAND MEXICO IN THE LATTER HALF OF THE 137FORECAST PERIOD. THE OFFICIAL TRACK FORECAST IS FAIRLY CLOSE TO 138THE PREVIOUS ONE AND IS ABOUT IN THE MIDDLE OF THE DYNAMICAL 139GUIDANCE. 140 141FORECAST POSITIONS AND MAX WINDS 142 143INITIAL 15/0900Z 18.5N 86.7W 55 KT 144 12HR VT 15/1800Z 19.1N 88.3W 50 KT...INLAND 145 24HR VT 16/0600Z 20.0N 90.5W 30 KT...INLAND 146 36HR VT 16/1800Z 20.7N 92.6W 45 KT 147 48HR VT 17/0600Z 21.3N 94.4W 60 KT 148 72HR VT 18/0600Z 21.4N 97.2W 75 KT 149 96HR VT 19/0600Z 21.0N 100.0W 25 KT...INLAND 150120HR VT 20/0600Z...DISSIPATED 151 152$$ 153FORECASTER PASCH 154 155 156WTNT43 KNHC 151440 157TCDAT3 158TROPICAL STORM KARL DISCUSSION NUMBER 4 159NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 1601000 AM CDT WED SEP 15 2010 161 162THE CENTER OF KARL MADE LANDFALL ALONG THE SOUTHEASTERN COAST OF THE 163YUCATAN PENINSULA OF MEXICO AT ABOUT 1245 UTC. BEFORE LANDFALL... 164AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT REPORTED A CENTRAL 165PRESSURE NEAR 991 MB WITH 850 MB FLIGHT-LEVEL WINDS OF 61 KT JUST 166NORTH OF THE CENTER. THE MAXIMUM RELIABLE SFMR WINDS WERE 50-55 167KT. BASED ON THIS...THE LANDFALL INTENSITY IS ESTIMATED AT 55 KT. 168DATA FROM THE RADAR IN BELIZE CITY SHOWED THAT KARL WAS DEVELOPING 169AN EYE AT LANDFALL...BUT AT THIS TIME THERE IS NO OTHER EVIDENCE TO 170SUGGEST IT REACHED HURRICANE STRENGTH AFTER THE HURRICANE HUNTER 171DEPARTED. 172 173KARL HAS BEEN MOVING A BIT TO THE LEFT OF THE PREVIOUS FORECASTS... 174WITH THE INITIAL MOTION NOW 280/12. KARL REMAINS ON THE SOUTH SIDE 175OF A LOW-/MID-LEVEL RIDGE CENTERED OVER THE NORTHERN GULF 176COAST...AND THIS FEATURE SHOULD STEER THE CYCLONE GENERALLY 177WEST-NORTHWESTWARD OR WESTWARD ACROSS THE SOUTHWESTERN GULF OF 178MEXICO INTO MAINLAND MEXICO. THERE IS SOME SPREAD IN THE 179GUIDANCE...WITH THE GFS...GFDL...AND HWRF MODELS SHOWING A MORE 180NORTHWARD MOTION THAN THE ECMWF...UKMET...CANADIAN...AND NOGAPS 181MODELS. THE NEW TRACK FORECAST WILL SPLIT THE DIFFERENCE BETWEEN 182THE TWO MODEL CAMPS AND LIE JUST TO THE SOUTH OF THE CONSENSUS 183MODELS. THE NEW TRACK IS SHIFTED A LITTLE TO THE SOUTH OF THE 184PREVIOUS TRACK FOR THE FIRST 48 HR. 185 186KARL SHOULD WEAKEN TO A TROPICAL DEPRESSION BY THE TIME IT REACHES 187THE WEST COAST OF THE YUCATAN PENINSULA. ONCE THE CENTER REACHES 188WATER...THE COMBINATION OF WARM SEA SURFACE TEMPERATURES AND LIGHT 189VERTICAL WIND SHEAR SHOULD ALLOW RE-INTENSIFICATION AS FORECAST BY 190ALL GUIDANCE. THE NEW INTENSITY FORECAST IS SIMILAR TO THE 191PREVIOUS FORECAST...CALLING FOR KARL TO BECOME A HURRICANE BEFORE 192MAKING LANDFALL IN MAINLAND MEXICO. KARL SHOULD WEAKEN AFTER ITS 193SECOND LANDFALL AND DISSIPATED OVER THE MOUNTAINS OF CENTRAL MEXICO 194BY 120 HR. 195 196FORECAST POSITIONS AND MAX WINDS 197 198INITIAL 15/1500Z 18.6N 88.2W 50 KT...INLAND 199 12HR VT 16/0000Z 19.1N 89.7W 35 KT...INLAND 200 24HR VT 16/1200Z 20.1N 91.7W 30 KT...OVER WATER 201 36HR VT 17/0000Z 20.9N 93.7W 45 KT 202 48HR VT 17/1200Z 21.3N 95.2W 60 KT 203 72HR VT 18/1200Z 21.5N 98.0W 75 KT...INLAND 204 96HR VT 19/1200Z 21.0N 101.0W 25 KT...INLAND 205120HR VT 20/1200Z...DISSIPATED 206 207$$ 208FORECASTER BEVEN 209 210 211WTNT43 KNHC 152032 212TCDAT3 213TROPICAL STORM KARL DISCUSSION NUMBER 5 214NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 215400 PM CDT WED SEP 15 2010 216 217KARL IS SLOWLY WEAKENING AS THE CENTER CROSSES THE YUCATAN 218PENINSULA. SATELLITE IMAGERY AND DATA FROM THE BELIZE CITY RADAR 219INDICATE THE CYCLONE CONTINUES TO PRODUCE STRONG CONVECTION...BUT 220THIS IS CURRENTLY CONFINED TO THE SOUTHWESTERN QUADRANT. THERE ARE 221NO OBSERVATION AVAILABLE NEAR THE CORE...AND THUS THE INITIAL 222INTENSITY OF 40 KT IS SOMEWHAT UNCERTAIN. 223 224THE INITIAL MOTION IS NOW 285/13. THE CYCLONE REMAINS ON THE SOUTH 225SIDE OF A LOW/MID-LEVEL RIDGE CENTERED OVER THE NORTHERN GULF 226COAST...AND THIS FEATURE SHOULD STEER THE CYCLONE GENERALLY 227WEST-NORTHWESTWARD OR WESTWARD ACROSS THE SOUTHWESTERN GULF OF 228MEXICO INTO MAINLAND MEXICO. THERE REMAINS SOME SPREAD IN THE 229GUIDANCE...WITH THE HWRF INDICATING A MORE NORTHWARD MOTION ON THE 230RIGHT SIDE OF THE GUIDANCE ENVELOPE AND THE GFDN A MORE WESTWARD 231MOTION ON THE LEFT. SEVERAL OF THE OTHER DYNAMICAL MODELS NOW 232FORECAST KARL TO SLOW ITS FORWARD MOTION BEFORE REACHING THE COAST 233OF MAINLAND MEXICO...AND ALSO FORECAST A TURN TO SOUTH OF WEST 234MOTION NEAR OR JUST AFTER LANDFALL. THE NEW FORECAST TRACK 235REFLECTS BOTH OF THESE POSSIBILITIES...WITH THE NEW TRACK BEING 236SIMILAR TO...BUT A LITTLE SLOWER THAN...THE PREVIOUS TRACK AFTER 23736 HR. 238 239KARL IS FORECAST TO WEAKEN TO A TROPICAL DEPRESSION BY THE TIME IT 240REACHES THE WEST COAST OF THE YUCATAN PENINSULA IN ABOUT 12 HR. 241ONCE THE CENTER REACHES WATER...THE COMBINATION OF WARM SEA SURFACE 242TEMPERATURES AND LIGHT VERTICAL WIND SHEAR SHOULD ALLOW 243RE-INTENSIFICATION AS FORECAST BY ALL GUIDANCE. IT SHOULD BE NOTED 244THAT THE HWRF...WHILE FORECASTING STRENGTHENING...HAS CONSISTENTLY 245KEPT KARL AT LESS THAN HURRICANE STRENGTH. GIVEN THE SEEMINGLY 246FAVORABLE ENVIRONMENT...THE INTENSITY FORECAST CALLS FOR KARL TO 247REACH HURRICANE STRENGTH OVER THE GULF OF MEXICO IN AGREEMENT WITH 248THE SHIPS AND LGEM MODELS. THE FORECAST SHOWS A PEAK INTENSITY OF 24970 KT...BUT KARL COULD BECOME STRONGER THAN THAT BETWEEN THE 48 AND 25072 HR FORECAST POINTS. 251 252FORECAST POSITIONS AND MAX WINDS 253 254INITIAL 15/2100Z 19.0N 89.4W 40 KT...INLAND 255 12HR VT 16/0600Z 19.6N 90.9W 30 KT...OVER WATER 256 24HR VT 16/1800Z 20.5N 92.7W 35 KT 257 36HR VT 17/0600Z 21.1N 94.4W 50 KT 258 48HR VT 17/1800Z 21.3N 95.7W 65 KT 259 72HR VT 18/1800Z 21.5N 98.5W 70 KT...INLAND 260 96HR VT 19/1800Z 21.0N 101.5W 25 KT...INLAND 261120HR VT 20/1800Z...DISSIPATED 262 263$$ 264FORECASTER BEVEN 265 266 267WTNT43 KNHC 160239 268TCDAT3 269TROPICAL STORM KARL DISCUSSION NUMBER 6 270NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 2711000 PM CDT WED SEP 15 2010 272 273DESPITE KARL BEING OVER LAND FOR SEVERAL HOURS...THE CLOUD PATTERN 274CONTINUES TO BE WELL ORGANIZED ON SATELLITE. THERE IS A RING OF 275VERY DEEP CONVECTION SURROUNDING A CLEAR AREA WHICH RESEMBLES AN 276EYE FEATURE...PROBABLY INDICATING THAT THE CYCLONE IS STILL 277VIGOROUS AT THE MID-LEVELS. HOWEVER...SURFACE OBSERVATIONS OVER THE 278YUCATAN PENINSULA SUGGEST THAT THE WINDS OF TROPICAL STORM FORCE 279ARE PROBABLY CONFINED TO RAINBANDS MAINLY OVER WATER. THE INITIAL 280INTENSITY IS KEPT AT 35 KNOTS. GIVEN THE OUTSTANDING STRUCTURE ON 281SATELLITE AND THE FAVORABLE ENVIRONMENT FOR INTENSIFICATION WHICH 282PREVAILS IN THE SOUTHERN GULF OF MEXICO...THE OFFICIAL FORECAST 283CALLS FOR RE-STRENGTHENING ONCE THE CIRCULATION MOVES BACK OVER 284WATER. KARL IS FORECAST TO REACH THE COAST OF THE STATE OF VERACRUZ 285WITHIN THE WATCH AREA AS A HURRICANE. HOWEVER...NONE OF THE 286GUIDANCE IS VERY AGGRESSIVE IN INTENSIFYING KARL. 287 288KARL APPEARS TO BE MOVING TOWARD THE WEST-NORTHWEST OR 290 DEGREES 289AT 13 KNOTS. THE CYCLONE IS TRAPPED ON THE SOUTH SIDE OF A NEARLY 290STATIONARY AND STRONG HIGH PRESSURE SYSTEM OVER THE NORTHERN GULF 291OF MEXICO. THIS STEERING PATTERN SHOULD FORCE KARL ON A GENERAL 292WEST-NORTHWEST TO WEST TRACK WITH A DECREASE IN FORWARD SPEED. THE 293FORECAST KEEPS KARL OVER THE EXTREME SOUTHERN GULF OF MEXICO FOR 294THE NEXT DAY OR SO...AND BRINGS KARL TO THE COAST OF MEXICO AS A 295HURRICANE WITHIN THE WATCH AREA IN ABOUT 48 HOURS. MOST OF THE 296TRACK GUIDANCE HAS BEEN VERY CONSISTENT IN KEEPING KARL ANCHORED IN 297THE SOUTHERN GULF SOUTH OF 22 DEGREES NORTH. 298 299 300FORECAST POSITIONS AND MAX WINDS 301 302INITIAL 16/0300Z 19.4N 90.7W 35 KT 303 12HR VT 16/1200Z 19.9N 92.0W 45 KT...OVER WATER 304 24HR VT 17/0000Z 20.7N 93.8W 50 KT 305 36HR VT 17/1200Z 21.0N 95.5W 55 KT 306 48HR VT 18/0000Z 21.5N 97.5W 65 KT 307 72HR VT 19/0000Z 21.5N 99.5W 25 KT...INLAND 308 96HR VT 20/0000Z 21.0N 102.0W 20 KT...INLAND 309120HR VT 21/0000Z...DISSIPATED 310 311$$ 312FORECASTER AVILA 313 314 315WTNT43 KNHC 160859 316TCDAT3 317TROPICAL STORM KARL DISCUSSION NUMBER 7 318NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 319400 AM CDT THU SEP 16 2010 320 321THE CENTER OF KARL EMERGED INTO THE BAY OF CAMPECHE BETWEEN 0330 AND 3220400 UTC AFTER MAINTAINING AN IMPRESSIVE CONVECTIVE STRUCTURE OVER 323LAND...WITH AN EYE-LIKE FEATURE INTERMITTENTLY SEEN IN INFRARED 324IMAGERY OVER THE PAST FEW HOURS. DVORAK INTENSITY ESTIMATES WERE 3253.5/55 KT FROM TAFB AND SAB. FOR THIS ADVISORY THE INITIAL 326INTENSITY IS INCREASED TO 45 KT BASED ON THE ASSUMPTION THAT THE 327WIND FIELD WILL TAKE SOME TIME TO SPIN UP AFTER MOVING OVER WATER. 328KARL SEEMS POISED TO TAKE ADVANTAGE OF THE FAVORABLE ENVIRONMENT OF 329VERY WARM WATERS AND LOW SHEAR OVER THE BAY OF CAMPECHE. ALSO... 330GIVEN THE SLOWER FORWARD SPEED OF THE TRACK GUIDANCE...KARL WILL 331LIKELY HAVE MORE TIME OVER WATER BEFORE MAKING LANDFALL IN MEXICO. 332THEREFORE...THE OFFICIAL FORECAST HAS BEEN ADJUSTED UPWARD FROM THE 333PREVIOUS PACKAGE AND SHOWS A PEAK INTENSITY OF 75 KT AROUND THE 334TIME OF LANDFALL...IN BEST AGREEMENT WITH THE SHIPS GUIDANCE. 335 336THE INITIAL MOTION IS 290/11 KT. KARL WILL REMAIN TO THE SOUTH OF A 337STRONG MID-LEVEL RIDGE THAT WILL RETROGRADE FROM THE NORTHERN GULF 338COAST TO THE SOUTH-CENTRAL UNITED STATES OVER THE NEXT COUPLE OF 339DAYS. THIS WILL STEER KARL WILL TOWARD THE WEST-NORTHWEST OR WEST 340OVER THE SOUTHERN GULF OF MEXICO FOR THE NEXT COUPLE OF DAYS...AND 341BRING THE CYCLONE TO THE COAST OF MEXICO WITHIN THE HURRICANE WATCH 342AREA LATE FRIDAY OR EARLY SATURDAY. WHILE THE MODELS REMAIN IN 343AGREEMENT ON THIS OVERALL SCENARIO...MUCH OF THE GUIDANCE FOR THIS 344CYCLE...WITH THE EXCEPTION OF THE UKMET AND THE ECMWF...HAS SLOWED 345AND SHIFTED SOUTH. THE OFFICIAL FORECAST HAS BEEN ADJUSTED IN THAT 346DIRECTION AND LIES BETWEEN THE UKMET AND ECMWF MODELS AND THE TVCN 347MULTI-MODEL CONSENSUS. GIVEN THE SOUTHWARD SHIFT IN THE TRACK... 348THE HURRICANE WATCH HAS BEEN EXTENDED SOUTHWARD TO PALMA SOLA. 349 350FORECAST POSITIONS AND MAX WINDS 351 352INITIAL 16/0900Z 19.8N 91.6W 45 KT 353 12HR VT 16/1800Z 20.3N 93.0W 55 KT 354 24HR VT 17/0600Z 20.7N 94.7W 60 KT 355 36HR VT 17/1800Z 21.0N 96.1W 70 KT 356 48HR VT 18/0600Z 21.1N 97.4W 75 KT...INLAND 357 72HR VT 19/0600Z 21.0N 100.5W 35 KT...INLAND 358 96HR VT 20/0600Z 21.0N 103.0W 20 KT...DISSIPATING INLAND 359120HR VT 21/0600Z...DISSIPATED 360 361$$ 362FORECASTER BRENNAN 363 364 365WTNT43 KNHC 161224 366TCDAT3 367TROPICAL STORM KARL SPECIAL DISCUSSION NUMBER 8 368NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 369730 AM CDT THU SEP 16 2010 370 371AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT FOUND THAT KARL WAS 372SOUTH OF THE PREVIOUS FORECAST TRACK BY ABOUT 30 N MI. THE PLANE 373MEASURED A CENTRAL PRESSURE OF 987 MB...WITH FLIGHT-LEVEL AND SFMR 374WINDS SUPPORTING AN INITIAL INTENSITY OF 55 KT. THIS SPECIAL 375ADVISORY IS BEING ISSUED TO SHIFT THE FIRST 36-48 HR OF THE 376FORECAST TRACK SOUTHWARD AND TO SIGNIFICANTLY INCREASE THE 377INTENSITY FORECAST. 378 379 380FORECAST POSITIONS AND MAX WINDS 381 382INITIAL 16/1230Z 19.7N 92.2W 55 KT 383 12HR VT 16/1800Z 20.1N 93.7W 65 KT 384 24HR VT 17/0600Z 20.5N 94.5W 75 KT 385 36HR VT 17/1800Z 20.8N 96.8W 85 KT 386 48HR VT 18/0600Z 21.0N 98.5W 75 KT...INLAND 387 72HR VT 19/0600Z 21.0N 101.0W 25 KT...INLAND 388 96HR VT 20/0600Z 21.0N 103.5W 20 KT...POST-TROP/REMNT LOW 389120HR VT 21/0600Z...DISSIPATED 390 391$$ 392FORECASTER BEVEN 393 394 395WTNT43 KNHC 161455 396TCDAT3 397HURRICANE KARL DISCUSSION NUMBER 9 398NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 3991000 AM CDT THU SEP 16 2010 400 401AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT HAS REPORTED 850 MB 402FLIGHT-LEVEL WINDS OF UP TO 76 KT IN A DEVELOPING EYEWALL...WITH 403SURFACE WINDS ESTIMATES OF 60-65 KT FROM THE SFMR. THE CENTRAL 404PRESSURE HAS FALLEN TO 983 MB. SATELLITE INTENSITY ESTIMATES FROM 405TAFB AND SAB ARE 77 KT. BASED ON THESE DATA...KARL IS UPGRADED TO 406A 65-KT HURRICANE. 407 408THE INITIAL MOTION IS 280/10. A LOW/MID-LEVEL RIDGE NORTH OF KARL 409SHOULD STEER THE HURRICANE ON A WESTWARD TO WEST-NORTHWARD TRACK 410FOR ROUGHLY THE NEXT 36 HR TO LANDFALL IN MEXICO...FOLLOWED BY A 411WESTWARD TO WEST-SOUTHWESTWARD MOTION AS THE RIDGE STRENGTHENS. 412THE TRACK MODEL GUIDANCE IS IN GENERAL AGREEMENT WITH THIS... 413ALTHOUGH THERE REMAINS SOME SPREAD ON JUST HOW FAR NORTH KARL COULD 414GET BEFORE MAKING LANDFALL. THE NEW FORECAST TRACK IS ADJUSTED 415SOUTH OF THE PREVIOUS TRACK BASED ON THE CURRENT POSITION AND 416MOTION...AND IS TO THE RIGHT OF THE CENTER OF THE GUIDANCE 417ENVELOPE. 418 419ENVIRONMENTAL CONDITIONS ARE VERY CONDUCIVE FOR STRENGTHENING ALONG 420THE FORECAST TRACK WITH WARM SEA SURFACE TEMPERATURES AND LIGHT 421VERTICAL WIND SHEAR. THUS...KARL IS EXPECTED TO STRENGTHEN 422STEADILY...AND POSSIBLY RAPIDLY. THE LGEM MODEL FORECASTS 100 KT 423IN 36 HR...THE SHIPS MODEL 85 KT...AND THE GFDL MODEL 97 KT. THE 424INTENSITY FORECAST IS FOR A 95 KT INTENSITY AT LANDFALL AS A BLEND 425OF THESE FORECASTS. IT IS NOT OUT OF THE QUESTION THAT KARL COULD 426BECOME A MAJOR HURRICANE BEFORE LANDFALL. AFTER LANDFALL...KARL 427SHOULD WEAKEN QUICKLY AS IT MOVES INTO THE MOUNTAINS OF MEXICO... 428AND IT IS EXPECTED TO DISSIPATE BY 96 HR. 429 430FORECAST POSITIONS AND MAX WINDS 431 432INITIAL 16/1500Z 19.7N 92.8W 65 KT 433 12HR VT 17/0000Z 20.0N 93.9W 75 KT 434 24HR VT 17/1200Z 20.3N 95.5W 85 KT 435 36HR VT 18/0000Z 20.5N 97.0W 95 KT 436 48HR VT 18/1200Z 20.5N 98.8W 50 KT...INLAND 437 72HR VT 19/1200Z 20.0N 101.5W 25 KT...INLAND 438 96HR VT 20/1200Z...DISSIPATED 439 440$$ 441FORECASTER BEVEN 442 443 444WTNT43 KNHC 162045 445TCDAT3 446HURRICANE KARL DISCUSSION NUMBER 10 447NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 448400 PM CDT THU SEP 16 2010 449 450REPORTS FROM A NOAA HURRICANE HUNTER AIRCRAFT INDICATE THAT KARL IS 451STRENGTHENING. A DROPSONDE IN THE EYE REPORTED A CENTRAL PRESSURE 452OF 977 MB...AND THERE WERE TWO SURFACE WIND ESTIMATES OF 69 KT FROM 453THE SFMR. IN ADDITION...A DROPSONDE IN THE NORTHWESTERN EYEWALL 454SUPPORTS 70 KT SURFACE WINDS...AND THE PLANE REPORTED FLIGHT-LEVEL 455WINDS OF 83 KT AT 12000 FT. THESE DATA SUPPORT RAISING THE INITIAL 456INTENSITY TO 70 KT. 457 458KARL HAS TURNED TO THE LEFT DURING THE PAST SEVERAL HOURS AND THE 459INITIAL MOTION IS NOW 270/10. A LOW/MID-LEVEL RIDGE NORTH OF KARL 460SHOULD CONTINUE TO STEER THE HURRICANE ON A GENERALLY WESTWARD TRACK 461FOR ABOUT THE NEXT 24 HR TO LANDFALL IN MEXICO...FOLLOWED BY A 462WESTWARD TO WEST-SOUTHWESTWARD MOTION AS THE RIDGE STRENGTHENS. 463OVERALL...THE ENVELOPE OF TRACK GUIDANCE HAS SHIFTED SOUTHWARD 464SINCE THE LAST ADVISORY...WITH ONLY THE ECMWF...CANADIAN...AND UKMET 465MODELS SHOWING ANY NORTHWARD COMPONENT TO THE MOTION BEFORE 466LANDFALL. THE NEW FORECAST TRACK IS SHIFTED SOUTH OF THE PREVIOUS 467ONE...SHOWING AN ALMOST DUE WEST MOTION UNTIL LANDFALL AND A 468SOUTH OF WEST MOTION THEREAFTER. THE NEW FORECAST TRACK IS TO 469THE SOUTH OF THE ECMWF...CANADIAN...AND UKMET MODELS...BUT TO THE 470NORTH OF THE OTHER DYNAMICAL MODELS AND THE CONSENSUS GUIDANCE. 471 472ENVIRONMENTAL CONDITIONS REMAIN VERY CONDUCIVE FOR STRENGTHENING 473ALONG THE FORECAST TRACK WITH WARM SEA SURFACE TEMPERATURES AND 474LIGHT VERTICAL WIND SHEAR. THUS...KARL IS EXPECTED TO STRENGTHEN 475STEADILY AND POSSIBLY RAPIDLY. THE LGEM...SHIPS...GFDL...AND 476FLORIDA STATE SUPERENSEMBLE ALL FORECAST KARL TO BECOME A CATEGORY 477TWO HURRICANE BEFORE LANDFALL...AND THE INTENSITY FORECAST IS FOR A 47885 KT LANDFALL INTENSITY AS A BLEND OF THESE FORECASTS. IT IS NOT 479OUT OF THE QUESTION THAT KARL COULD BECOME A MAJOR HURRICANE BEFORE 480LANDFALL. AFTER LANDFALL...KARL SHOULD WEAKEN QUICKLY AS IT MOVES 481INTO THE MOUNTAINS OF MEXICO...AND IT IS EXPECTED TO DISSIPATE BY 48296 HR IF NOT SOONER. 483 484THE NEW FORECAST TRACK HAS REQUIRED WARNINGS TO BE EXTENDED FARTHER 485SOUTH ALONG THE COAST OF MEXICO. IT SHOULD BE NOTED THAT THE NEW 486FORECAST TRACK CALLS FOR LANDFALL IN ABOUT 24 HOURS AS COMPARED TO 48736 HOURS FOR THE PREVIOUS FORECAST...WHICH HAS REDUCED THE AMOUNT 488OF TIME AVAILABLE TO MAKE PREPARATIONS. 489 490FORECAST POSITIONS AND MAX WINDS 491 492INITIAL 16/2100Z 19.6N 93.7W 70 KT 493 12HR VT 17/0600Z 19.7N 94.9W 75 KT 494 24HR VT 17/1800Z 19.7N 96.2W 85 KT 495 36HR VT 18/0600Z 19.6N 97.6W 55 KT...INLAND 496 48HR VT 18/1800Z 19.5N 99.1W 30 KT...INLAND 497 72HR VT 19/1800Z 19.0N 102.0W 25 KT...INLAND 498 96HR VT 20/1800Z...DISSIPATED 499 500$$ 501FORECASTER BEVEN 502 503 504WTNT43 KNHC 170240 505TCDAT3 506HURRICANE KARL DISCUSSION NUMBER 11 507NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 5081000 PM CDT THU SEP 16 2010 509 510THE CLOUD PATTERN HAS CONTINUED TO BECOME BETTER ORGANIZED DURING 511THE PAST FEW HOURS AND SATELLITE ESTIMATES FROM BOTH TAFB AND SAB 512HAVE REACHED T-NUMBERS OF 5.0 ON THE DVORAK SCALE OR 90 KNOTS AT 5130000 UTC. SINCE THEN THE EYE HAS BECOME A LITTLE MORE DISTINCT... 514SURROUNDED BY A RING OF VERY DEEP CONVECTION. A RECONNAISSANCE 515PLANE CROSSED THE EYE A FEW TIMES THIS EVENING. THE CENTRAL 516PRESSURE DROPPED TO 968 MB AND THE FLIGHT LEVEL WINDS REACHED 90 517KNOTS IN THE NORTHWEST QUADRANT ACCOMPANIED BY SFMR MEASUREMENTS OF 51885 KNOTS. BASED ON THIS...THE INITIAL INTENSITY HAS BEEN INCREASED 519TO 85 KNOTS. THIS ESTIMATE COULD BE ON THE LOW SIDE GIVEN THAT THE 520SATELLITE PRESENTATION CONTINUES TO IMPROVE AS WE SPEAK. KARL HAS 521LESS THAN A DAY BEFORE LANDFALL...BUT GIVEN THE VERY FAVORABLE 522ENVIRONMENT...THE FORECAST NOW CALLS FOR KARL TO BE A CATEGORY 523THREE HURRICANE AT LANDFALL. WEAKENING IS EXPECTED AFTER LANDFALL 524OVER THE VERY HIGH TERRAIN OF MEXICO...BUT KARL WILL LIKELY PRODUCE 525TORRENTIAL RAINS. 526 527KARL IS MOVING TOWARD THE WEST OR 270 DEGREES AT 8 KNOTS...TRAPPED 528SOUTH OF A PERSISTENT HIGH PRESSURE SYSTEM OVER THE NORTHERN GULF OF 529MEXICO. THIS GENERAL TRACK IS NOT EXPECTED TO CHANGE THROUGH THE 530ENTIRE FORECAST PERIOD. DESPITE SOME DIFFERENCES IN SPEED AMONG 531MODELS...THE OVERALL MODEL TREND IS TO KEEP KARL ON A STRAIGHT 532WESTWARD PATH OVER THE BAY OF CAMPECHE FOLLOWED BY A LANDFALL OVER 533THE COAST OF MEXICO WITHIN THE HURRICANE WARNING AREA LATE FRIDAY. 534THIS IS REFLECTED IN THE OFFICIAL FORECAST. 535 536 537FORECAST POSITIONS AND MAX WINDS 538 539INITIAL 17/0300Z 19.7N 94.5W 85 KT 540 12HR VT 17/1200Z 19.7N 95.6W 100 KT 541 24HR VT 18/0000Z 19.7N 96.8W 65 KT...INLAND 542 36HR VT 18/1200Z 19.5N 98.5W 30 KT...INLAND 543 48HR VT 19/0000Z 19.5N 100.0W 20 KT...INLAND 544 72HR VT 20/0000Z...DISSIPATING INLAND 545 546$$ 547FORECASTER AVILA 548 549 550WTNT43 KNHC 170837 551TCDAT3 552HURRICANE KARL DISCUSSION NUMBER 12 553NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 554400 AM CDT FRI SEP 17 2010 555 556THE AIR FORCE HURRICANE HUNTER AIRCRAFT MEASURED A MAXIMUM FLIGHT 557LEVEL WIND OF 105 KT...AN SFMR MAXIMUM OF 86 KT...AND A MINIMUM 558PRESSURE OF 967 MB AS IT EXITED KARL BEFORE AROUND 0530 UTC. 559SINCE THEN...CLOUD TOPS AROUND THE EYE HAVE COOLED BELOW -70C AND 560THE EYE TEMPERATURE HAS WARMED...AND DVORAK CURRENT INTENSITY 561ESTIMATES FROM TAFB AND SAB WERE T6.0/115 KT AT 0600 UTC. THE 562INITIAL INTENSITY IS INCREASED AT 105 KT FOR THIS ADVISORY... 563ASSUMING THAT THE WIND FIELD CONTINUES TO LAG THE SATELLITE 564PRESENTATION...BUT THIS COULD BE CONSERVATIVE. ANOTHER HURRICANE 565HUNTER AIRCRAFT WILL BE INVESTIGATING KARL THIS MORNING TO PROVIDE 566ADDITIONAL DATA ON THE INTENSITY OF THE HURRICANE. KARL STILL HAS 567THE OPPORTUNITY TO STRENGTHEN FURTHER OVER VERY WARM WATERS PRIOR 568TO LANDFALL LATER TODAY...AND THE OFFICIAL FORECAST REFLECTS THIS. 569AFTER LANDFALL...KARL SHOULD WEAKEN STEADILY OVER THE MOUNTAINS OF 570MEXICO AND THE SURFACE CIRCULATION IS EXPECTED TO DISSIPATE IN 571ABOUT 48 HOURS. HOWEVER...A HEAVY RAINFALL THREAT WILL CONTINUE 572AFTER THIS TIME OVER THE HIGH TERRAIN. 573 574THE INITIAL MOTION ESTIMATE REMAINS WESTWARD...OR 270 DEGREES...AT 8 575KNOTS. KARL WILL BE STEERED WESTWARD BY A LARGE MID- TO UPPER- 576LEVEL RIDGE OVER THE NORTHERN GULF OF MEXICO. WHILE THERE 577REMAINS SOME SPREAD IN THE GUIDANCE ON THE FORWARD SPEED OF 578KARL...THE OFFICIAL FORECAST IS SIMILAR TO THE PREVIOUS ONE AND 579SHOWS A WESTWARD MOTION OF 7 TO 8 KNOTS UNTIL LANDFALL LATER TODAY. 580AFTER THAT TIME A MOTION JUST SOUTH OF DUE WEST IS EXPECTED UNTIL 581DISSIPATION. 582 583FORECAST POSITIONS AND MAX WINDS 584 585INITIAL 17/0900Z 19.7N 95.3W 105 KT 586 12HR VT 17/1800Z 19.7N 96.3W 120 KT 587 24HR VT 18/0600Z 19.6N 97.6W 65 KT...INLAND 588 36HR VT 18/1800Z 19.5N 99.2W 30 KT...INLAND 589 48HR VT 19/0600Z 19.4N 100.5W 20 KT...DISSIPATING INLAND 590 72HR VT 20/0600Z...DISSIPATED 591 592$$ 593FORECASTER BRENNAN 594 595 596WTNT43 KNHC 171447 597TCDAT3 598HURRICANE KARL DISCUSSION NUMBER 13 599NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 6001000 AM CDT FRI SEP 17 2010 601 602KARL APPEARS TO HAVE PEAKED IN INTENSITY DURING THE PAST FEW HOURS. 603THE 10 NM WIDE EYE HAS BECOME LESS DISTINCT IN SATELLITE IMAGERY AND 604THE CLOUD TOPS IN THE EYEWALL HAVE WARMED. IN ADDITION...THE 605CENTRAL PRESSURE HAS RISEN SINCE 12Z...WITH THE LATEST EXTRAPOLATED 606PRESSURE OF 967 MB. THE AIR FORCE RESERVE HURRICANE HUNTER 607REPORTED AN ESTIMATED SURFACE WIND OF 103 KT FROM THE STEPPED 608FREQUENCY MICROWAVE RADIOMETER IN THE SOUTHEASTERN EYEWALL...WITH 609700 MB FLIGHT-LEVEL WINDS OF 120 KT. THESE DATA ARE THE BASIS FOR 610THE INITIAL INTENSITY OF 105 KT. 611 612KARL HAS TURNED TO THE LEFT DURING THE PAST SEVERAL HOURS WITH THE 613INITIAL MOTION NOW 260/7. A MID/UPPER-LEVEL RIDGE OVER NORTHERN 614MEXICO SHOULD STEER THE STORM WESTWARD OR WEST-SOUTHWESTWARD FOR 615THE NEXT 48-72 HR UNTIL THE CYCLONE DISSIPATES OVER THE MOUNTAINS 616OF MEXICO. THE NEW FORECAST TRACK HAS BEEN SHIFTED SOUTH OF THE 617PREVIOUS ONE BASED ON THE INITIAL POSITION AND MOTION...AND IT LIES 618TO THE LEFT OF THE CENTER OF THE GUIDANCE ENVELOPE. 619 620GIVEN THE CURRENT TRENDS...LITTLE CHANGE IN STRENGTH IS LIKELY 621BEFORE LANDFALL. AFTER LANDFALL...KARL SHOULD WEAKEN STEADILY OVER 622THE MOUNTAINS OF MEXICO...AND THE SURFACE CIRCULATION IS EXPECTED 623TO DISSIPATE IN 48-72 HOURS. HOWEVER...A HEAVY RAINFALL THREAT WILL 624CONTINUE AFTER THIS TIME...ESPECIALLY OVER THE HIGH TERRAIN. 625 626FORECAST POSITIONS AND MAX WINDS 627 628INITIAL 17/1500Z 19.4N 95.9W 105 KT 629 12HR VT 18/0000Z 19.2N 96.9W 80 KT...INLAND 630 24HR VT 18/1200Z 19.1N 98.2W 40 KT...INLAND 631 36HR VT 19/0000Z 19.1N 99.7W 25 KT...INLAND 632 48HR VT 19/1200Z 19.1N 101.2W 20 KT...POST-TROP/REMNT LOW 633 72HR VT 20/1200Z...DISSIPATED 634 635$$ 636FORECASTER BEVEN 637 638 639WTNT43 KNHC 172031 640TCDAT3 641HURRICANE KARL DISCUSSION NUMBER 14 642NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 643400 PM CDT FRI SEP 17 2010 644 645KARL MADE LANDFALL JUST NORTH-NORTHWEST OF VERACRUZ MEXICO AT 646ABOUT 1630Z. BEFORE LANDFALL...THE CENTRAL PRESSURE RAPIDLY ROSE 647FROM 957 MB TO 976 MB OVER A 4.5 HOUR PERIOD FOR REASONS THAT ARE 648NOT READILY APPARENT. DESPITE THIS...THE AIRCRAFT-REPORTED WINDS 649SUPPORTED MAJOR HURRICANE INTENSITY UNTIL LANDFALL. SINCE LANDFALL 650THE HURRICANE HAS STEADILY WEAKENED...AND THE INITIAL INTENSITY OF 65180 KT MAY BE A BIT GENEROUS. KARL SHOULD CONTINUE TO WEAKEN AS IT 652MOVES OVER THE MOUNTAINS OF MEXICO...AND THE CYCLONE IS LIKELY TO 653DISSIPATE COMPLETELY BY 48 HR. 654 655THE INITIAL MOTION IS 250/8. A MID-LEVEL RIDGE OVER NORTHERN MEXICO 656SHOULD CONTINUE TO STEER KARL TOWARD THE WEST-SOUTHWEST OR WEST 657UNTIL DISSIPATION. 658 659FORECAST POSITIONS AND MAX WINDS 660 661INITIAL 17/2100Z 19.1N 96.6W 80 KT...INLAND 662 12HR VT 18/0600Z 18.8N 97.7W 50 KT...INLAND 663 24HR VT 18/1800Z 18.7N 99.1W 30 KT...INLAND 664 36HR VT 19/0600Z 18.7N 100.6W 25 KT...INLAND 665 48HR VT 19/1800Z...DISSIPATED 666 667$$ 668FORECASTER BEVEN 669 670 671WTNT43 KNHC 180232 672TCDAT3 673TROPICAL DEPRESSION KARL DISCUSSION NUMBER 15 674NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 6751000 PM CDT FRI SEP 17 2010 676 677KARL MOVED OVER THE HIGH MOUNTAINS OF SOUTHERN MEXICO AND QUICKLY 678WEAKENED. THE CLOUD PATTERN AS WELL AS THE CIRCULATION ARE VERY 679DISRUPTED WHILE THE DEEP CONVECTION HAS PRACTICALLY VANISHED. THERE 680ARE NO SURFACE OBSERVATIONS NEARBY SUGGESTING THE PRESENCE OF 681STRONG WINDS BUT THE BEST ESTIMATE OF THE INITIAL INTENSITY IS 30 682KNOTS...WITH PERHAPS STRONGER WIND GUSTS AT HIGHER ELEVATIONS. 683KARL HAS BEEN MOVING TOWARD THE WEST-SOUTHWEST OR 250 DEGREES AT 6 684KNOTS. THIS GENERAL MOTION IS EXPECTED TO CONTINUE UNTIL 685DISSIPATION WITHIN THE NEXT 12 HOURS...OR LESS. 686 687 688FORECAST POSITIONS AND MAX WINDS 689 690INITIAL 18/0300Z 18.6N 97.4W 30 KT 691 12HR VT 18/1200Z 18.1N 98.2W 25 KT...DISSIPATING INLAND 692 24HR VT 19/0000Z...DISSIPATED 693 694$$ 695FORECASTER AVILA 696 697 698WTNT43 KNHC 142052 699TCDAT3 700TROPICAL STORM KARL DISCUSSION NUMBER 1 701NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 702500 PM EDT TUE SEP 14 2010 703 704AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING THE LOW 705PRESSURE AREA IN THE NORTHWESTERN CARIBBEAN SEA FOUND A SMALL AND 706VIGOROUS WIND/PRESSURE CENTER INSIDE THE LARGER CYCLONIC ENVELOPE. 707THE MAXIMUM FLIGHT-LEVEL WINDS WERE 41 KT AT LESS THAN 1500 FT JUST 708EAST OF THE CENTER...AND THE SFMR ESTIMATED RELIABLE-LOOKING WINDS 709OF 35 KT OUTSIDE OF THE HEAVY RAIN AREAS. THE MINIMUM CENTRAL 710PRESSURE WAS 1001 MB. BASED ON THESE DATA...THE SYSTEM IS UPGRADED 711STRAIGHT TO TROPICAL STORM KARL WITH AN INITIAL INTENSITY OF 35 KT. 712 713THE INITIAL MOTION IS 295/13. KARL IS LOCATED ON THE SOUTH SIDE OF 714A DEEP-LAYER RIDGE CENTERED ALONG THE NORTHERN GULF COAST. THE 715TRACK GUIDANCE IS IN GOOD AGREEMENT THAT THE RIDGE SHOULD STEER 716KARL GENERALLY WEST-NORTHWESTWARD ACROSS THE YUCATAN PENINSULA INTO 717THE SOUTHWESTERN GULF OF MEXICO...FOLLOWED BY A GENERAL WESTWARD 718MOTION TOWARD MAINLAND MEXICO. THERE IS SOME SPREAD IN THE TRACK 719GUIDANCE OVER THE GULF OF MEXICO...WITH SOME OF THE DYNAMICAL 720MODELS FORECASTING A SOUTH-OF-WEST MOTION BEFORE KARL REACHES THE 721COAST OF MAINLAND MEXICO. THE FORECAST TRACK WILL SHOW A WESTWARD 722MOTION AFTER 72 HR...AND OVERALL IT LIES DOWN THE CENTER OF THE 723GUIDANCE ENVELOPE. 724 725KARL IS IN AN ENVIRONMENT OF LIGHT EASTERLY VERTICAL WIND SHEAR... 726AND THIS IS FORECAST TO PERSIST FOR THE NEXT 4-5 DAYS. THE MAJOR 727INFLUENCE ON THE INTENSITY WILL BE LAND INTERACTION. WHILE THE 728INTENSITY FORECAST SHOWS KARL WITH 45-KT WINDS OVER EASTERN 729YUCATAN...THE STORM COULD REACH A HIGHER INTENSITY BETWEEN THE 12 730AND 24 HR FORECAST POINTS. OVER THE GULF OF MEXICO...KARL SHOULD 731RE-INTENSIFY...WITH THE SHIPS AND GFDL MODELS CALLING FOR IT TO 732BECOME A HURRICANE. THE INTENSITY FORECAST IS A BIT MORE 733CONSERVATIVE DUE TO UNCERTAINTY ABOUT WHAT KIND OF STRUCTURE KARL 734WILL HAVE AFTER CROSSING THE YUCATAN PENINSULA. AFTER FINAL 735LANDFALL IN MEXICO...KARL SHOULD EVENTUALLY DISSIPATE OVER THE 736MOUNTAINS OF CENTRAL MEXICO. 737 738 739FORECAST POSITIONS AND MAX WINDS 740 741INITIAL 14/2100Z 18.3N 84.2W 35 KT 74212HR VT 15/0600Z 18.9N 86.0W 40 KT 74324HR VT 15/1800Z 19.6N 88.1W 45 KT...INLAND 74436HR VT 16/0600Z 20.4N 90.3W 30 KT...INLAND 74548HR VT 16/1800Z 21.0N 92.6W 35 KT...OVER WATER 74672HR VT 17/1800Z 21.5N 96.0W 55 KT 74796HR VT 18/1800Z 21.5N 99.5W 30 KT...INLAND 748120HR VT 19/1800Z...DISSIPATED 749 750$$ 751FORECASTER BEVEN 752 753 754 755000 756 757WTNT43 KNHC 150243 758TCDAT3 759TROPICAL STORM KARL DISCUSSION NUMBER 2 760NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 7611000 PM CDT TUE SEP 14 2010 762 763THE AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT INVESTIGATING KARL 764EARLIER THIS EVENING FOUND PEAK 925 MB FLIGHT-LEVEL WINDS OF 49 KT 765AND SEVERAL BELIEVABLE 34-39 KT SFMR SURFACE WINDS JUST NORTH OF 766THE CENTER AS IT EXITED THE STORM. THESE DATA WERE THE BASIS FOR 767THE INCREASE IN INTENSITY IN THE 0000 UTC INTERMEDIATE ADVISORY. 768THE ORGANIZATION OF THE CYCLONE HAS CHANGED LITTLE SINCE THAT 769TIME...THEREFORE THE INITIAL INTENSITY REMAINS 40 KT. THE NEXT AIR 770FORCE RESERVE RECONNAISSANCE MISSION IS SCHEDULED TO REACH KARL 771AROUND 0600 UTC. 772 773THE AIRCRAFT FIXES AND A COUPLE OF RECENT SSMIS MICROWAVE IMAGES 774SHOW THAT THE CENTER IS LOCATED NEAR THE EASTERN EDGE OF THE SMALL 775MASS OF DEEP CONVECTION...WHICH SUGGESTS THAT THERE IS SOME LIGHT 776EASTERLY SHEAR. THE SHEAR...HOWEVER...IS NOT EXPECTED TO BE 777INHIBITIVE FOR STRENGTHENING...AND SOME INTENSIFICATION IS POSSIBLE 778BEFORE KARL REACHES THE EAST COAST OF THE YUCATAN PENINSULA. OVER 779THE SOUTHWESTERN GULF OF MEXICO...WATERS ARE WARM AND THE SHEAR IS 780EXPECTED TO BE LIGHT...THEREFORE STRENGTHENING IS EXPECTED. THE 781GFDL...LGEM...SHIPS...AND FLORIDA STATE SUPERENSEMBLE ALL SHOW KARL 782AT HURRICANE STRENGTH BEFORE IT REACHES THE COAST OF MAINLAND 783MEXICO IN ABOUT 72 HOURS. THERE IS STILL SOME UNCERTAINTY ABOUT 784WHAT KIND OF STRUCTURE KARL WILL HAVE AFTER CROSSING THE YUCATAN 785PENINSULA...HOWEVER GIVEN THE FAVORABLE CONDITIONS AND MODEL 786AGREEMENT...THE OFFICIAL FORECAST BRINGS KARL TO HURRICANE STATUS 787AT THAT TIME. 788 789THE INITIAL MOTION IS 290/13. THE TRACK FORECAST PHILOSOPHY REMAINS 790UNCHANGED. KARL IS EXPECTED TO MOVE GENERALLY WEST-NORTHWESTWARD 791AROUND THE SOUTHERN PORTION OF A DEEP-LAYER RIDGE ALONG THE 792NORTHERN GULF COAST. THE TRACK GUIDANCE IS IN GOOD AGREEMENT 793THROUGH 48 HOURS...WITH INCREASED SPREAD THEREAFTER...AS SOME OF THE 794MODELS TURN KARL WEST-SOUTHWESTWARD NEAR THE COAST OF MAINLAND 795MEXICO. THE NEW NHC TRACK IS ESSENTIALLY AN UPDATE OF THE PREVIOUS 796ADVISORY AND IS IN GOOD AGREEMENT WITH THE GFS AND ECMWF MODELS. 797 798FORECAST POSITIONS AND MAX WINDS 799 800INITIAL 15/0300Z 18.6N 85.5W 40 KT 80112HR VT 15/1200Z 19.2N 87.3W 50 KT 80224HR VT 16/0000Z 20.0N 89.5W 30 KT...INLAND 80336HR VT 16/1200Z 20.7N 91.6W 35 KT 80448HR VT 17/0000Z 21.1N 93.4W 50 KT 80572HR VT 18/0000Z 21.5N 96.7W 65 KT 80696HR VT 19/0000Z 21.5N 100.5W 25 KT...INLAND 807120HR VT 20/0000Z...DISSIPATED 808 809$$ 810FORECASTER BROWN 811 812 813 814000 815 816WTNT43 KNHC 150840 817TCDAT3 818TROPICAL STORM KARL DISCUSSION NUMBER 3 819NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 820400 AM CDT WED SEP 15 2010 821 822THE AIR FORCE RESERVE HURRICANE HUNTERS INVESTIGATING KARL EARLY 823THIS MORNING FOUND THAT THE STORM HAS STRENGTHENED SOMEWHAT SINCE 824THE LAST RECONNAISSANCE MISSION ON TUESDAY AFTERNOON. THE CENTRAL 825PRESSURE HAS FALLEN TO 995 MB AND THE MAXIMUM UNCONTAMINATED 826SFMR-OBSERVED SURFACE WIND VELOCITIES WERE ABOUT 55 KT...WHICH IS 827THE VALUE USED FOR THE CURRENT ADVISORY INTENSITY. SATELLITE 828IMAGES SHOW THAT A RATHER SYMMETRICAL UPPER-LEVEL OUTFLOW PATTERN 829IS DEVELOPING OVER KARL...SO SOME ADDITIONAL INTENSIFICATION COULD 830OCCUR BEFORE LANDFALL. FORTUNATELY...THE TIME IS SHORT BEFORE THE 831CENTER SHOULD CROSS THE COAST. 832 833KARL WOBBLED WESTWARD A FEW HOURS AGO BUT THE LATEST AIRCRAFT FIXES 834INDICATE THAT A WEST-NORTHWESTWARD MOTION...AROUND 285/11...HAS 835RESUMED. BASED ON GLOBAL MODEL FORECASTS...A MID-TROPOSPHERIC 836RIDGE SHOULD REMAIN IN PLACE TO THE NORTH OF THE TROPICAL CYCLONE 837FOR THE NEXT 2 TO 3 DAYS. THEREFORE A WEST-NORTHWESTWARD TO 838WESTWARD TRACK APPEARS LIKELY...WHICH WOULD TAKE THE CENTER ACROSS 839THE NORTHEASTERN COAST OF MAINLAND MEXICO IN THE LATTER HALF OF THE 840FORECAST PERIOD. THE OFFICIAL TRACK FORECAST IS FAIRLY CLOSE TO 841THE PREVIOUS ONE AND IS ABOUT IN THE MIDDLE OF THE DYNAMICAL 842GUIDANCE. 843 844FORECAST POSITIONS AND MAX WINDS 845 846INITIAL 15/0900Z 18.5N 86.7W 55 KT 84712HR VT 15/1800Z 19.1N 88.3W 50 KT...INLAND 84824HR VT 16/0600Z 20.0N 90.5W 30 KT...INLAND 84936HR VT 16/1800Z 20.7N 92.6W 45 KT 85048HR VT 17/0600Z 21.3N 94.4W 60 KT 85172HR VT 18/0600Z 21.4N 97.2W 75 KT 85296HR VT 19/0600Z 21.0N 100.0W 25 KT...INLAND 853120HR VT 20/0600Z...DISSIPATED 854 855$$ 856FORECASTER PASCH 857 858 859 860000 861 862WTNT43 KNHC 151440 863TCDAT3 864TROPICAL STORM KARL DISCUSSION NUMBER 4 865NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 8661000 AM CDT WED SEP 15 2010 867 868THE CENTER OF KARL MADE LANDFALL ALONG THE SOUTHEASTERN COAST OF THE 869YUCATAN PENINSULA OF MEXICO AT ABOUT 1245 UTC. BEFORE LANDFALL... 870AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT REPORTED A CENTRAL 871PRESSURE NEAR 991 MB WITH 850 MB FLIGHT-LEVEL WINDS OF 61 KT JUST 872NORTH OF THE CENTER. THE MAXIMUM RELIABLE SFMR WINDS WERE 50-55 873KT. BASED ON THIS...THE LANDFALL INTENSITY IS ESTIMATED AT 55 KT. 874DATA FROM THE RADAR IN BELIZE CITY SHOWED THAT KARL WAS DEVELOPING 875AN EYE AT LANDFALL...BUT AT THIS TIME THERE IS NO OTHER EVIDENCE TO 876SUGGEST IT REACHED HURRICANE STRENGTH AFTER THE HURRICANE HUNTER 877DEPARTED. 878 879KARL HAS BEEN MOVING A BIT TO THE LEFT OF THE PREVIOUS FORECASTS... 880WITH THE INITIAL MOTION NOW 280/12. KARL REMAINS ON THE SOUTH SIDE 881OF A LOW-/MID-LEVEL RIDGE CENTERED OVER THE NORTHERN GULF 882COAST...AND THIS FEATURE SHOULD STEER THE CYCLONE GENERALLY 883WEST-NORTHWESTWARD OR WESTWARD ACROSS THE SOUTHWESTERN GULF OF 884MEXICO INTO MAINLAND MEXICO. THERE IS SOME SPREAD IN THE 885GUIDANCE...WITH THE GFS...GFDL...AND HWRF MODELS SHOWING A MORE 886NORTHWARD MOTION THAN THE ECMWF...UKMET...CANADIAN...AND NOGAPS 887MODELS. THE NEW TRACK FORECAST WILL SPLIT THE DIFFERENCE BETWEEN 888THE TWO MODEL CAMPS AND LIE JUST TO THE SOUTH OF THE CONSENSUS 889MODELS. THE NEW TRACK IS SHIFTED A LITTLE TO THE SOUTH OF THE 890PREVIOUS TRACK FOR THE FIRST 48 HR. 891 892KARL SHOULD WEAKEN TO A TROPICAL DEPRESSION BY THE TIME IT REACHES 893THE WEST COAST OF THE YUCATAN PENINSULA. ONCE THE CENTER REACHES 894WATER...THE COMBINATION OF WARM SEA SURFACE TEMPERATURES AND LIGHT 895VERTICAL WIND SHEAR SHOULD ALLOW RE-INTENSIFICATION AS FORECAST BY 896ALL GUIDANCE. THE NEW INTENSITY FORECAST IS SIMILAR TO THE 897PREVIOUS FORECAST...CALLING FOR KARL TO BECOME A HURRICANE BEFORE 898MAKING LANDFALL IN MAINLAND MEXICO. KARL SHOULD WEAKEN AFTER ITS 899SECOND LANDFALL AND DISSIPATED OVER THE MOUNTAINS OF CENTRAL MEXICO 900BY 120 HR. 901 902FORECAST POSITIONS AND MAX WINDS 903 904INITIAL 15/1500Z 18.6N 88.2W 50 KT...INLAND 90512HR VT 16/0000Z 19.1N 89.7W 35 KT...INLAND 90624HR VT 16/1200Z 20.1N 91.7W 30 KT...OVER WATER 90736HR VT 17/0000Z 20.9N 93.7W 45 KT 90848HR VT 17/1200Z 21.3N 95.2W 60 KT 90972HR VT 18/1200Z 21.5N 98.0W 75 KT...INLAND 91096HR VT 19/1200Z 21.0N 101.0W 25 KT...INLAND 911120HR VT 20/1200Z...DISSIPATED 912 913$$ 914FORECASTER BEVEN 915 916 917 918000 919 920WTNT43 KNHC 152032 921TCDAT3 922TROPICAL STORM KARL DISCUSSION NUMBER 5 923NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 924400 PM CDT WED SEP 15 2010 925 926KARL IS SLOWLY WEAKENING AS THE CENTER CROSSES THE YUCATAN 927PENINSULA. SATELLITE IMAGERY AND DATA FROM THE BELIZE CITY RADAR 928INDICATE THE CYCLONE CONTINUES TO PRODUCE STRONG CONVECTION...BUT 929THIS IS CURRENTLY CONFINED TO THE SOUTHWESTERN QUADRANT. THERE ARE 930NO OBSERVATION AVAILABLE NEAR THE CORE...AND THUS THE INITIAL 931INTENSITY OF 40 KT IS SOMEWHAT UNCERTAIN. 932 933THE INITIAL MOTION IS NOW 285/13. THE CYCLONE REMAINS ON THE SOUTH 934SIDE OF A LOW/MID-LEVEL RIDGE CENTERED OVER THE NORTHERN GULF 935COAST...AND THIS FEATURE SHOULD STEER THE CYCLONE GENERALLY 936WEST-NORTHWESTWARD OR WESTWARD ACROSS THE SOUTHWESTERN GULF OF 937MEXICO INTO MAINLAND MEXICO. THERE REMAINS SOME SPREAD IN THE 938GUIDANCE...WITH THE HWRF INDICATING A MORE NORTHWARD MOTION ON THE 939RIGHT SIDE OF THE GUIDANCE ENVELOPE AND THE GFDN A MORE WESTWARD 940MOTION ON THE LEFT. SEVERAL OF THE OTHER DYNAMICAL MODELS NOW 941FORECAST KARL TO SLOW ITS FORWARD MOTION BEFORE REACHING THE COAST 942OF MAINLAND MEXICO...AND ALSO FORECAST A TURN TO SOUTH OF WEST 943MOTION NEAR OR JUST AFTER LANDFALL. THE NEW FORECAST TRACK 944REFLECTS BOTH OF THESE POSSIBILITIES...WITH THE NEW TRACK BEING 945SIMILAR TO...BUT A LITTLE SLOWER THAN...THE PREVIOUS TRACK AFTER 94636 HR. 947 948KARL IS FORECAST TO WEAKEN TO A TROPICAL DEPRESSION BY THE TIME IT 949REACHES THE WEST COAST OF THE YUCATAN PENINSULA IN ABOUT 12 HR. 950ONCE THE CENTER REACHES WATER...THE COMBINATION OF WARM SEA SURFACE 951TEMPERATURES AND LIGHT VERTICAL WIND SHEAR SHOULD ALLOW 952RE-INTENSIFICATION AS FORECAST BY ALL GUIDANCE. IT SHOULD BE NOTED 953THAT THE HWRF...WHILE FORECASTING STRENGTHENING...HAS CONSISTENTLY 954KEPT KARL AT LESS THAN HURRICANE STRENGTH. GIVEN THE SEEMINGLY 955FAVORABLE ENVIRONMENT...THE INTENSITY FORECAST CALLS FOR KARL TO 956REACH HURRICANE STRENGTH OVER THE GULF OF MEXICO IN AGREEMENT WITH 957THE SHIPS AND LGEM MODELS. THE FORECAST SHOWS A PEAK INTENSITY OF 95870 KT...BUT KARL COULD BECOME STRONGER THAN THAT BETWEEN THE 48 AND 95972 HR FORECAST POINTS. 960 961FORECAST POSITIONS AND MAX WINDS 962 963INITIAL 15/2100Z 19.0N 89.4W 40 KT...INLAND 96412HR VT 16/0600Z 19.6N 90.9W 30 KT...OVER WATER 96524HR VT 16/1800Z 20.5N 92.7W 35 KT 96636HR VT 17/0600Z 21.1N 94.4W 50 KT 96748HR VT 17/1800Z 21.3N 95.7W 65 KT 96872HR VT 18/1800Z 21.5N 98.5W 70 KT...INLAND 96996HR VT 19/1800Z 21.0N 101.5W 25 KT...INLAND 970120HR VT 20/1800Z...DISSIPATED 971 972$$ 973FORECASTER BEVEN 974 975 976 977000 978 979WTNT43 KNHC 160239 980TCDAT3 981TROPICAL STORM KARL DISCUSSION NUMBER 6 982NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 9831000 PM CDT WED SEP 15 2010 984 985DESPITE KARL BEING OVER LAND FOR SEVERAL HOURS...THE CLOUD PATTERN 986CONTINUES TO BE WELL ORGANIZED ON SATELLITE. THERE IS A RING OF 987VERY DEEP CONVECTION SURROUNDING A CLEAR AREA WHICH RESEMBLES AN 988EYE FEATURE...PROBABLY INDICATING THAT THE CYCLONE IS STILL 989VIGOROUS AT THE MID-LEVELS. HOWEVER...SURFACE OBSERVATIONS OVER THE 990YUCATAN PENINSULA SUGGEST THAT THE WINDS OF TROPICAL STORM FORCE 991ARE PROBABLY CONFINED TO RAINBANDS MAINLY OVER WATER. THE INITIAL 992INTENSITY IS KEPT AT 35 KNOTS. GIVEN THE OUTSTANDING STRUCTURE ON 993SATELLITE AND THE FAVORABLE ENVIRONMENT FOR INTENSIFICATION WHICH 994PREVAILS IN THE SOUTHERN GULF OF MEXICO...THE OFFICIAL FORECAST 995CALLS FOR RE-STRENGTHENING ONCE THE CIRCULATION MOVES BACK OVER 996WATER. KARL IS FORECAST TO REACH THE COAST OF THE STATE OF VERACRUZ 997WITHIN THE WATCH AREA AS A HURRICANE. HOWEVER...NONE OF THE 998GUIDANCE IS VERY AGGRESSIVE IN INTENSIFYING KARL. 999 1000KARL APPEARS TO BE MOVING TOWARD THE WEST-NORTHWEST OR 290 DEGREES 1001AT 13 KNOTS. THE CYCLONE IS TRAPPED ON THE SOUTH SIDE OF A NEARLY 1002STATIONARY AND STRONG HIGH PRESSURE SYSTEM OVER THE NORTHERN GULF 1003OF MEXICO. THIS STEERING PATTERN SHOULD FORCE KARL ON A GENERAL 1004WEST-NORTHWEST TO WEST TRACK WITH A DECREASE IN FORWARD SPEED. THE 1005FORECAST KEEPS KARL OVER THE EXTREME SOUTHERN GULF OF MEXICO FOR 1006THE NEXT DAY OR SO...AND BRINGS KARL TO THE COAST OF MEXICO AS A 1007HURRICANE WITHIN THE WATCH AREA IN ABOUT 48 HOURS. MOST OF THE 1008TRACK GUIDANCE HAS BEEN VERY CONSISTENT IN KEEPING KARL ANCHORED IN 1009THE SOUTHERN GULF SOUTH OF 22 DEGREES NORTH. 1010 1011 1012FORECAST POSITIONS AND MAX WINDS 1013 1014INITIAL 16/0300Z 19.4N 90.7W 35 KT 101512HR VT 16/1200Z 19.9N 92.0W 45 KT...OVER WATER 101624HR VT 17/0000Z 20.7N 93.8W 50 KT 101736HR VT 17/1200Z 21.0N 95.5W 55 KT 101848HR VT 18/0000Z 21.5N 97.5W 65 KT 101972HR VT 19/0000Z 21.5N 99.5W 25 KT...INLAND 102096HR VT 20/0000Z 21.0N 102.0W 20 KT...INLAND 1021120HR VT 21/0000Z...DISSIPATED 1022 1023$$ 1024FORECASTER AVILA 1025 1026 1027 1028000 1029 1030WTNT43 KNHC 160859 1031TCDAT3 1032TROPICAL STORM KARL DISCUSSION NUMBER 7 1033NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 1034400 AM CDT THU SEP 16 2010 1035 1036THE CENTER OF KARL EMERGED INTO THE BAY OF CAMPECHE BETWEEN 0330 AND 10370400 UTC AFTER MAINTAINING AN IMPRESSIVE CONVECTIVE STRUCTURE OVER 1038LAND...WITH AN EYE-LIKE FEATURE INTERMITTENTLY SEEN IN INFRARED 1039IMAGERY OVER THE PAST FEW HOURS. DVORAK INTENSITY ESTIMATES WERE 10403.5/55 KT FROM TAFB AND SAB. FOR THIS ADVISORY THE INITIAL 1041INTENSITY IS INCREASED TO 45 KT BASED ON THE ASSUMPTION THAT THE 1042WIND FIELD WILL TAKE SOME TIME TO SPIN UP AFTER MOVING OVER WATER. 1043KARL SEEMS POISED TO TAKE ADVANTAGE OF THE FAVORABLE ENVIRONMENT OF 1044VERY WARM WATERS AND LOW SHEAR OVER THE BAY OF CAMPECHE. ALSO... 1045GIVEN THE SLOWER FORWARD SPEED OF THE TRACK GUIDANCE...KARL WILL 1046LIKELY HAVE MORE TIME OVER WATER BEFORE MAKING LANDFALL IN MEXICO. 1047THEREFORE...THE OFFICIAL FORECAST HAS BEEN ADJUSTED UPWARD FROM THE 1048PREVIOUS PACKAGE AND SHOWS A PEAK INTENSITY OF 75 KT AROUND THE 1049TIME OF LANDFALL...IN BEST AGREEMENT WITH THE SHIPS GUIDANCE. 1050 1051THE INITIAL MOTION IS 290/11 KT. KARL WILL REMAIN TO THE SOUTH OF A 1052STRONG MID-LEVEL RIDGE THAT WILL RETROGRADE FROM THE NORTHERN GULF 1053COAST TO THE SOUTH-CENTRAL UNITED STATES OVER THE NEXT COUPLE OF 1054DAYS. THIS WILL STEER KARL WILL TOWARD THE WEST-NORTHWEST OR WEST 1055OVER THE SOUTHERN GULF OF MEXICO FOR THE NEXT COUPLE OF DAYS...AND 1056BRING THE CYCLONE TO THE COAST OF MEXICO WITHIN THE HURRICANE WATCH 1057AREA LATE FRIDAY OR EARLY SATURDAY. WHILE THE MODELS REMAIN IN 1058AGREEMENT ON THIS OVERALL SCENARIO...MUCH OF THE GUIDANCE FOR THIS 1059CYCLE...WITH THE EXCEPTION OF THE UKMET AND THE ECMWF...HAS SLOWED 1060AND SHIFTED SOUTH. THE OFFICIAL FORECAST HAS BEEN ADJUSTED IN THAT 1061DIRECTION AND LIES BETWEEN THE UKMET AND ECMWF MODELS AND THE TVCN 1062MULTI-MODEL CONSENSUS. GIVEN THE SOUTHWARD SHIFT IN THE TRACK... 1063THE HURRICANE WATCH HAS BEEN EXTENDED SOUTHWARD TO PALMA SOLA. 1064 1065FORECAST POSITIONS AND MAX WINDS 1066 1067INITIAL 16/0900Z 19.8N 91.6W 45 KT 106812HR VT 16/1800Z 20.3N 93.0W 55 KT 106924HR VT 17/0600Z 20.7N 94.7W 60 KT 107036HR VT 17/1800Z 21.0N 96.1W 70 KT 107148HR VT 18/0600Z 21.1N 97.4W 75 KT...INLAND 107272HR VT 19/0600Z 21.0N 100.5W 35 KT...INLAND 107396HR VT 20/0600Z 21.0N 103.0W 20 KT...DISSIPATING INLAND 1074120HR VT 21/0600Z...DISSIPATED 1075 1076$$ 1077FORECASTER BRENNAN 1078 1079 1080 1081 1082WTNT43 KNHC 161224 1083TCDAT3 1084TROPICAL STORM KARL SPECIAL DISCUSSION NUMBER 8 1085NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 1086730 AM CDT THU SEP 16 2010 1087 1088AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT FOUND THAT KARL WAS 1089SOUTH OF THE PREVIOUS FORECAST TRACK BY ABOUT 30 N MI. THE PLANE 1090MEASURED A CENTRAL PRESSURE OF 987 MB...WITH FLIGHT-LEVEL AND SFMR 1091WINDS SUPPORTING AN INITIAL INTENSITY OF 55 KT. THIS SPECIAL 1092ADVISORY IS BEING ISSUED TO SHIFT THE FIRST 36-48 HR OF THE 1093FORECAST TRACK SOUTHWARD AND TO SIGNIFICANTLY INCREASE THE 1094INTENSITY FORECAST. 1095 1096 1097FORECAST POSITIONS AND MAX WINDS 1098 1099INITIAL 16/1230Z 19.7N 92.2W 55 KT 110012HR VT 16/1800Z 20.1N 93.7W 65 KT 110124HR VT 17/0600Z 20.5N 94.5W 75 KT 110236HR VT 17/1800Z 20.8N 96.8W 85 KT 110348HR VT 18/0600Z 21.0N 98.5W 75 KT...INLAND 110472HR VT 19/0600Z 21.0N 101.0W 25 KT...INLAND 110596HR VT 20/0600Z 21.0N 103.5W 20 KT...POST-TROP/REMNT LOW 1106120HR VT 21/0600Z...DISSIPATED 1107 1108$$ 1109FORECASTER BEVEN 1110 1111 1112 1113 1114WTNT43 KNHC 161455 1115TCDAT3 1116HURRICANE KARL DISCUSSION NUMBER 9 1117NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 11181000 AM CDT THU SEP 16 2010 1119 1120AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT HAS REPORTED 850 MB 1121FLIGHT-LEVEL WINDS OF UP TO 76 KT IN A DEVELOPING EYEWALL...WITH 1122SURFACE WINDS ESTIMATES OF 60-65 KT FROM THE SFMR. THE CENTRAL 1123PRESSURE HAS FALLEN TO 983 MB. SATELLITE INTENSITY ESTIMATES FROM 1124TAFB AND SAB ARE 77 KT. BASED ON THESE DATA...KARL IS UPGRADED TO 1125A 65-KT HURRICANE. 1126 1127THE INITIAL MOTION IS 280/10. A LOW/MID-LEVEL RIDGE NORTH OF KARL 1128SHOULD STEER THE HURRICANE ON A WESTWARD TO WEST-NORTHWARD TRACK 1129FOR ROUGHLY THE NEXT 36 HR TO LANDFALL IN MEXICO...FOLLOWED BY A 1130WESTWARD TO WEST-SOUTHWESTWARD MOTION AS THE RIDGE STRENGTHENS. 1131THE TRACK MODEL GUIDANCE IS IN GENERAL AGREEMENT WITH THIS... 1132ALTHOUGH THERE REMAINS SOME SPREAD ON JUST HOW FAR NORTH KARL COULD 1133GET BEFORE MAKING LANDFALL. THE NEW FORECAST TRACK IS ADJUSTED 1134SOUTH OF THE PREVIOUS TRACK BASED ON THE CURRENT POSITION AND 1135MOTION...AND IS TO THE RIGHT OF THE CENTER OF THE GUIDANCE 1136ENVELOPE. 1137 1138ENVIRONMENTAL CONDITIONS ARE VERY CONDUCIVE FOR STRENGTHENING ALONG 1139THE FORECAST TRACK WITH WARM SEA SURFACE TEMPERATURES AND LIGHT 1140VERTICAL WIND SHEAR. THUS...KARL IS EXPECTED TO STRENGTHEN 1141STEADILY...AND POSSIBLY RAPIDLY. THE LGEM MODEL FORECASTS 100 KT 1142IN 36 HR...THE SHIPS MODEL 85 KT...AND THE GFDL MODEL 97 KT. THE 1143INTENSITY FORECAST IS FOR A 95 KT INTENSITY AT LANDFALL AS A BLEND 1144OF THESE FORECASTS. IT IS NOT OUT OF THE QUESTION THAT KARL COULD 1145BECOME A MAJOR HURRICANE BEFORE LANDFALL. AFTER LANDFALL...KARL 1146SHOULD WEAKEN QUICKLY AS IT MOVES INTO THE MOUNTAINS OF MEXICO... 1147AND IT IS EXPECTED TO DISSIPATE BY 96 HR. 1148 1149FORECAST POSITIONS AND MAX WINDS 1150 1151INITIAL 16/1500Z 19.7N 92.8W 65 KT 115212HR VT 17/0000Z 20.0N 93.9W 75 KT 115324HR VT 17/1200Z 20.3N 95.5W 85 KT 115436HR VT 18/0000Z 20.5N 97.0W 95 KT 115548HR VT 18/1200Z 20.5N 98.8W 50 KT...INLAND 115672HR VT 19/1200Z 20.0N 101.5W 25 KT...INLAND 115796HR VT 20/1200Z...DISSIPATED 1158 1159$$ 1160FORECASTER BEVEN 1161 1162 1163 1164000 1165 1166WTNT43 KNHC 162045 1167TCDAT3 1168HURRICANE KARL DISCUSSION NUMBER 10 1169NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 1170400 PM CDT THU SEP 16 2010 1171 1172REPORTS FROM A NOAA HURRICANE HUNTER AIRCRAFT INDICATE THAT KARL IS 1173STRENGTHENING. A DROPSONDE IN THE EYE REPORTED A CENTRAL PRESSURE 1174OF 977 MB...AND THERE WERE TWO SURFACE WIND ESTIMATES OF 69 KT FROM 1175THE SFMR. IN ADDITION...A DROPSONDE IN THE NORTHWESTERN EYEWALL 1176SUPPORTS 70 KT SURFACE WINDS...AND THE PLANE REPORTED FLIGHT-LEVEL 1177WINDS OF 83 KT AT 12000 FT. THESE DATA SUPPORT RAISING THE INITIAL 1178INTENSITY TO 70 KT. 1179 1180KARL HAS TURNED TO THE LEFT DURING THE PAST SEVERAL HOURS AND THE 1181INITIAL MOTION IS NOW 270/10. A LOW/MID-LEVEL RIDGE NORTH OF KARL 1182SHOULD CONTINUE TO STEER THE HURRICANE ON A GENERALLY WESTWARD TRACK 1183FOR ABOUT THE NEXT 24 HR TO LANDFALL IN MEXICO...FOLLOWED BY A 1184WESTWARD TO WEST-SOUTHWESTWARD MOTION AS THE RIDGE STRENGTHENS. 1185OVERALL...THE ENVELOPE OF TRACK GUIDANCE HAS SHIFTED SOUTHWARD 1186SINCE THE LAST ADVISORY...WITH ONLY THE ECMWF...CANADIAN...AND UKMET 1187MODELS SHOWING ANY NORTHWARD COMPONENT TO THE MOTION BEFORE 1188LANDFALL. THE NEW FORECAST TRACK IS SHIFTED SOUTH OF THE PREVIOUS 1189ONE...SHOWING AN ALMOST DUE WEST MOTION UNTIL LANDFALL AND A 1190SOUTH OF WEST MOTION THEREAFTER. THE NEW FORECAST TRACK IS TO 1191THE SOUTH OF THE ECMWF...CANADIAN...AND UKMET MODELS...BUT TO THE 1192NORTH OF THE OTHER DYNAMICAL MODELS AND THE CONSENSUS GUIDANCE. 1193 1194ENVIRONMENTAL CONDITIONS REMAIN VERY CONDUCIVE FOR STRENGTHENING 1195ALONG THE FORECAST TRACK WITH WARM SEA SURFACE TEMPERATURES AND 1196LIGHT VERTICAL WIND SHEAR. THUS...KARL IS EXPECTED TO STRENGTHEN 1197STEADILY AND POSSIBLY RAPIDLY. THE LGEM...SHIPS...GFDL...AND 1198FLORIDA STATE SUPERENSEMBLE ALL FORECAST KARL TO BECOME A CATEGORY 1199TWO HURRICANE BEFORE LANDFALL...AND THE INTENSITY FORECAST IS FOR A 120085 KT LANDFALL INTENSITY AS A BLEND OF THESE FORECASTS. IT IS NOT 1201OUT OF THE QUESTION THAT KARL COULD BECOME A MAJOR HURRICANE BEFORE 1202LANDFALL. AFTER LANDFALL...KARL SHOULD WEAKEN QUICKLY AS IT MOVES 1203INTO THE MOUNTAINS OF MEXICO...AND IT IS EXPECTED TO DISSIPATE BY 120496 HR IF NOT SOONER. 1205 1206THE NEW FORECAST TRACK HAS REQUIRED WARNINGS TO BE EXTENDED FARTHER 1207SOUTH ALONG THE COAST OF MEXICO. IT SHOULD BE NOTED THAT THE NEW 1208FORECAST TRACK CALLS FOR LANDFALL IN ABOUT 24 HOURS AS COMPARED TO 120936 HOURS FOR THE PREVIOUS FORECAST...WHICH HAS REDUCED THE AMOUNT 1210OF TIME AVAILABLE TO MAKE PREPARATIONS. 1211 1212FORECAST POSITIONS AND MAX WINDS 1213 1214INITIAL 16/2100Z 19.6N 93.7W 70 KT 121512HR VT 17/0600Z 19.7N 94.9W 75 KT 121624HR VT 17/1800Z 19.7N 96.2W 85 KT 121736HR VT 18/0600Z 19.6N 97.6W 55 KT...INLAND 121848HR VT 18/1800Z 19.5N 99.1W 30 KT...INLAND 121972HR VT 19/1800Z 19.0N 102.0W 25 KT...INLAND 122096HR VT 20/1800Z...DISSIPATED 1221 1222$$ 1223FORECASTER BEVEN 1224 1225 1226 1227 1228WTNT43 KNHC 172031 1229TCDAT3 1230HURRICANE KARL DISCUSSION NUMBER 14 1231NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 1232400 PM CDT FRI SEP 17 2010 1233 1234KARL MADE LANDFALL JUST NORTH-NORTHWEST OF VERACRUZ MEXICO AT 1235ABOUT 1630Z. BEFORE LANDFALL...THE CENTRAL PRESSURE RAPIDLY ROSE 1236FROM 957 MB TO 976 MB OVER A 4.5 HOUR PERIOD FOR REASONS THAT ARE 1237NOT READILY APPARENT. DESPITE THIS...THE AIRCRAFT-REPORTED WINDS 1238SUPPORTED MAJOR HURRICANE INTENSITY UNTIL LANDFALL. SINCE LANDFALL 1239THE HURRICANE HAS STEADILY WEAKENED...AND THE INITIAL INTENSITY OF 124080 KT MAY BE A BIT GENEROUS. KARL SHOULD CONTINUE TO WEAKEN AS IT 1241MOVES OVER THE MOUNTAINS OF MEXICO...AND THE CYCLONE IS LIKELY TO 1242DISSIPATE COMPLETELY BY 48 HR. 1243 1244THE INITIAL MOTION IS 250/8. A MID-LEVEL RIDGE OVER NORTHERN MEXICO 1245SHOULD CONTINUE TO STEER KARL TOWARD THE WEST-SOUTHWEST OR WEST 1246UNTIL DISSIPATION. 1247 1248FORECAST POSITIONS AND MAX WINDS 1249 1250INITIAL 17/2100Z 19.1N 96.6W 80 KT...INLAND 125112HR VT 18/0600Z 18.8N 97.7W 50 KT...INLAND 125224HR VT 18/1800Z 18.7N 99.1W 30 KT...INLAND 125336HR VT 19/0600Z 18.7N 100.6W 25 KT...INLAND 125448HR VT 19/1800Z...DISSIPATED 1255 1256$$ 1257FORECASTER BEVEN 1258 1259 1260 1261000 1262 1263WTNT43 KNHC 180232 1264TCDAT3 1265TROPICAL DEPRESSION KARL DISCUSSION NUMBER 15 1266NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 12671000 PM CDT FRI SEP 17 2010 1268 1269KARL MOVED OVER THE HIGH MOUNTAINS OF SOUTHERN MEXICO AND QUICKLY 1270WEAKENED. THE CLOUD PATTERN AS WELL AS THE CIRCULATION ARE VERY 1271DISRUPTED WHILE THE DEEP CONVECTION HAS PRACTICALLY VANISHED. THERE 1272ARE NO SURFACE OBSERVATIONS NEARBY SUGGESTING THE PRESENCE OF 1273STRONG WINDS BUT THE BEST ESTIMATE OF THE INITIAL INTENSITY IS 30 1274KNOTS...WITH PERHAPS STRONGER WIND GUSTS AT HIGHER ELEVATIONS. 1275KARL HAS BEEN MOVING TOWARD THE WEST-SOUTHWEST OR 250 DEGREES AT 6 1276KNOTS. THIS GENERAL MOTION IS EXPECTED TO CONTINUE UNTIL 1277DISSIPATION WITHIN THE NEXT 12 HOURS...OR LESS. 1278 1279 1280FORECAST POSITIONS AND MAX WINDS 1281 1282INITIAL 18/0300Z 18.6N 97.4W 30 KT 128312HR VT 18/1200Z 18.1N 98.2W 25 KT...DISSIPATING INLAND 128424HR VT 19/0000Z...DISSIPATED 1285 1286$$ 1287FORECASTER AVILA 1288 1289 1290 1291000 1292 1293WTNT43 KNHC 180830 1294TCDAT3 1295TROPICAL DEPRESSION KARL DISCUSSION NUMBER 16 1296NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL132010 1297400 AM CDT SAT SEP 18 2010 1298 1299SATELLITE IMAGES AND SURFACE OBSERVATIONS INDICATE THAT KARL HAS 1300DISSIPATED OVER THE HIGH MOUNTAINS OF SOUTHERN MEXICO. A FEW 1301THUNDERSTORMS REMAIN NEAR THE REMNANT MID-LEVEL CIRCULATION...AND 1302LOCALLY HEAVY RAINFALL IS EXPECTED TO BE THE MAIN THREAT WITH THIS 1303SYSTEM OVER THE WEEKEND UNTIL THE ENTIRE CIRCULATION DISSIPATES. 1304 1305FORECAST POSITIONS AND MAX WINDS 1306 1307INITIAL 18/0900Z 18.5N 97.6W 20 KT...DISSIPATED 1308 1309$$ 1310FORECASTER BLAKE 1311 1312 1313