10 0 NESTED GRID MODEL (NGM) 21 1 AVIATION MODEL (AVN) 32 2 MEDIUM RANGE FORECAST (MRF) MODEL 43 3 GLOBAL DATA ASSIMILATION SYSTEM (GDAS) FORECAST MODEL 54 4 PRIOR SOUNDINGS (WITHIN 3 HOURS OF CURRENT TIME) 65 5 CLIMATOLOGY 715 15 MISSING VALUE 8