000 FXUS63 KEAX 161039 AFDEAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 439 AM CST MON FEB 16 2009 .DISCUSSION... HIGH PRESSURE CENTERED OVER MO WILL SHIFT EAST WHILE SHORTWAVE RIDGING OVER THE CENTRAL/SOUTHERN HIGH PLAINS SLOWLY FLATTENS IN ADVANCE OF ENERGY BEING EJECTED FROM THE BASE OF THE CLOSED LOW OFF THE CA COAST. WATER VAPOR SATELLITE IMAGERY SHOWS A LONG FETCH OF SUBTROPICAL HIGH LEVEL MOISTURE STREAMING NORTHEAST ACROSS OLD MEXICO AND INTO MO. SHOULD SEE A GOOD DEAL OF CIRRUS CLOUDINESS TODAY WHICH WILL RESULT IN ONLY FILTERED SUNSHINE. UNSURE HOW THICK THIS CLOUD COVER WILL GET BUT BELIEVE IT WILL BE ENOUGH TO FAVOR THE COOLER MET MOS NUMBERS TODAY. GFS/NAM PROGGED SOUNDINGS AND CONDENSATION PRESSURE DEFICIT PROGS HAVE SHOWN QUITE A BIT OF CONSISTENCY THE PAST COUPLE OF RUNS ON SPREADING GULF STRATUS QUICKLY NORTHWARD TONIGHT. THE MODELS HAVE TENDED TO BE OVERLY GENEROUS WITH THE RETURN OF LOW LEVEL MOISTURE THIS WINTER...AND NOTING THE DRY AIR STILL OVER SOUTH TX...THINK THEY ARE ONCE AGAIN DOING THIS. HOWEVER...HAVE TO LEAN TOWARDS THE IDEA OF INCREASING LOW CLOUDS TOMORROW GIVEN THE RUN-TO-RUN CONSISTENCY BOTH MODELS HAVE SHOWN WITH THIS SYSTEM. MAX TEMPERATURE FORECAST IS BANKING ON THE LOW CLOUDS SCATTERING OUT IN THE AFTERNOON. SHOULD THEY FAIL TO DO THAT THEN THE TEMPERATURE FORECAST IS LIKELY 5-8F TOO WARM. WILL ALSO MENTION THE THREAT OF PATCHY MORNING DRIZZLE OR FREEZING DRIZZLE. BY TUESDAY NIGHT MOST OF THE UPPER SUPPORT WILL BE MOVING THROUGH THE CWA BUT THE VORTICITY STRUCTURE WILL BE ELONGATING/STRINGING OUT. THIS WILL AFFECT THE AMOUNT OF DEEPENING OF THE SURFACE LOW AND ITS EVENTUAL TRACK. NAM MODEL WAS DISCOUNTED AS IT HAS BEEN ERRATIC WITH THIS SYSTEM AND LOOKS TOO FAR SOUTH WITH THE TRACK. THE ECMWF/GFS/UKMET ARE SIMILAR. WILL USE A BLEND OF THESE MODELS AND FOLLOW THE HPC TRACK OF THE SURFACE LOW WHICH TAKES THIS FEATURE ACROSS NORTHERN MO TUESDAY NIGHT. TEMPERATURES WILL STAY UP DURING THE NIGHT AS MOST OF THE CWA WILL REMAIN IN THE WARM SECTOR. TAIL END OF THE DEFORMATION ZONE WILL DRAG ACROSS NORTHERN MO LATE TUESDAY NIGHT/EARLY WEDNESDAY MORNING. COULD SEE SOME LIGHT SNOW BUT PROGGED SOUNDINGS DO NOT SHOW MUCH SATURATION WITHIN THE FAVORABLE DENDRITIC SNOW GROWTH REGION. THAT COMBINED WITH TEMPERATURES STAYING ABOVE FREEZING FOR MOST OF THE NIGHT DO NOT FAVOR MUCH SNOW ACCUMULATION. COLD AIR ADVECTION WILL SWEEP THROUGH THE CWA WEDNESDAY SO HIGHS WILL LIKELY BE SEEN EARLY IN THE MORNING WITH SLOWLY FALLING TEMPERATURES ALL DAY. A SECOND STRONGER UPPER SYSTEM WILL SWOOP SOUTHWARD FROM SOUTH CENTRAL CANADA ON WEDNESDAY AND USHER IN ANOTHER SURGE OF COLD AIR AND BRISK NORTHWEST WINDS FOR WEDNESDAY NIGHT AND THURSDAY. 19 && .AVIATION... VFR CONDITIONS EXPECTED THROUGH THE TAF PERIOD. WITH SURFACE RIDGE SLIDING TO THE EAST OF THE REGION TONIGHT...A GRADUAL WIND SHIFT FROM EAST TO SOUTHEAST WILL OCCUR. WINDS WILL INCREASE BY MONDAY AFTERNOON AS THE PRESSURE GRADIENT STARTS TO TIGHTEN WITH A LEE SIDE SURFACE LOW DEVELOPING IN SOUTHEAST COLORADO. MOISTURE RETURN SHOULD BE IN THE MID AND UPPER LEVELS UNTIL MONDAY EVENING. MAY START TO SEE SOME LOWER LEVEL MOISTURE BY LATE MONDAY EVENING WITH THE RETURN FLOW...BUT LOWER CIGS TOO UNCERTAIN AT THIS TIME TO MENTION. PC && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. $$