000 FXUS63 KEAX 250858 AFDEAX AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO 258 AM CST WED NOV 25 2009 .DISCUSSION... MAIN CONCERN FOR THIS FORECAST DEALS PRIMARILY WITH TEMPERATURES... WITH A CLIPPER SYSTEM REINFORCING COOLER AIR IN THE REGION TODAY AND THURSDAY. THEN UPPER RIDGING WILL ALLOW FOR A NICE WARM UP HEADING INTO THE WEEKEND. SYNOPSIS: WATER VAPOR IMAGERY SHOWED A FAST MOVING CLIPPER SYSTEM DIVING THROUGH THE NORTHERN PLAINS. MODELS SEEM TO BE TRACKING THIS SYSTEM WELL WITH ALL SHOWING A STRONG PV ANOMALY ON THE 1.5 PVU SURFACE IN DECENT CORRELATION TO THE WV IMAGERY. 00Z UA CHARTS SHOW AN APPROXIMATELY 100 TO 110 KT UPPER JET IS ASSOCIATED WITH THIS ANOMALY. IN THE MID LEVELS...VERY COLD AIR IS ASSOCIATED WITH THIS SYSTEM WITH -13C AND -32C AT 700MB AND 500MB RESPECTIVELY AT GGW. THIS INDICATES THAT AS THE SYSTEM MOVES OVER US STEEP MID LEVEL LAPSE RATES CAN BE EXPECTED. AT THE SURFACE...A WOUND UP LOW PRESSURE AREA CAN BE SEEN IN THE UPPER MISSISSIPPI VALLEY IN ASSOCIATION WITH THE WAVE THAT MOVED THROUGH TUESDAY. ANOTHER LOW PRESSURE AREA WAS FORMING AHEAD OF THE CLIPPER SYSTEM IN EASTERN SD/SOUTHWEST MN WITH 4MB 6 HOUR PRESSURE FALLS NOTED. TODAY THROUGH TONIGHT: THE UPPER LEVEL PV ANOMALY WILL BEGIN TO IMPACT THE AREA LATER THIS MORNING. AS THIS FORCING MECHANISM APPROACHES THE REGION THERE MAY BE ENOUGH UPWARD MOTION TO WRING OUT A FEW SNOW FLURRIES THROUGH MID MORNING IN NORTHERN/NORTHWEST MISSOURI. AS THE LOW LEVELS WARM UP THIS WOULD LIKELY TREND TO SPRINKLES. SO CONTINUED MENTION OF THIS AHEAD OF THE ANOMALY ACROSS WESTERN AND CENTRAL MISSOURI. AS THE ANOMALY WRAPS UP JUST EAST OF THE AREA IT MAY TRIGGER A FEW SHOWERS ACROSS NORTHERN/NORTHEAST MISSOURI. FORECAST SOUNDINGS SHOW A FAIR AMOUNT OF INSTABILITY FOR THIS TIME OF YEAR THROUGHOUT THE REGION DUE TO THE STEEP MID LEVEL LAPSE RATES. THE BEST MOISTURE HOWEVER SHOULD STAY GENERALLY NORTH OF MISSOURI RIVER. SO KEPT AFTERNOON SHOWER MENTION TO NORTHERN/NORTHEASTERN SECTIONS OF THE FORECAST AREA. AS COLD AIR FILTERS INTO THE AREA A TRANSITION TO SNOW SHOULD OCCUR DURING THE OVERNIGHT HOURS. AGAIN THIS SHOULD BE CONFINED TO NORTHERN/NORTHEASTERN SECTIONS OF THE FORECAST AREA. OVERALL... MOISTURE SEEMS FAIRLY LIMITED SO ONLY TRACE AMOUNTS OF PRECIPITATION ARE EXPECTED. THANKSGIVING DAY: A CHILLY BUT FAIR WEATHER DAY IS EXPECTED FOR THANKSGIVING. AS THE UPPER SYSTEM PULLS AWAY SKIES WILL CLEAR FROM WEST TO EAST ACROSS THE REGION AND SOMEWHAT BRISK NORTHWEST WINDS WILL PREVAIL. WITH MIXING TO ABOUT 900MB HIGHS SHOULD TOP OUT IN THE LOWER TO MID 40S WITH THE WARMER TEMPERATURES ACROSS WESTERN MISSOURI AND EASTERN KANSAS. FRIDAY THROUGH SATURDAY: UPPER LEVEL RIDGING AND WARMING TEMPERATURES ALOFT WILL ALLOW FOR A NICE WARM UP TO START THE WEEKEND. HIGHS SHOULD BE ABLE TO REBOUND INTO THE MID TO UPPER 50S FOR FRIDAY WITH SIMILAR READINGS FOR SATURDAY. THE UPPER RIDGING SHOULD KEEP THINGS DRY AS WELL. A DECENT LOW LEVEL JET DEVELOPS SATURDAY MORNING BUT FORECAST SOUNDINGS ARE SO DRY I DO NOT EXPECT ANYTHING FROM THIS FEATURE SO THE FORECAST REMAINS DRY THROUGH SATURDAY. MODELS WANT TO BRING A FRONT THROUGH THE AREA LATE SATURDAY NIGHT OR EARLY SUNDAY MORNING. WHILE FORECAST SOUNDINGS FOR THIS TIME FRAME ARE VERY DRY THERE MAY BE ENOUGH FORCING TO TRIGGER SOMETHING. GOING FORECAST HAD SLIGHT CHANCE MENTION FOR THIS TIME FRAME AND SEE NO REASON TO ADJUST THAT AT THIS POINT IN TIME. CDB && .AVIATION... FOR THE 06Z TAFS...THE CLOUDS HAVE JUST ABOUT CLEARED THE TERMINALS AS THE UPPER LEVEL LOW PULLS RAPIDLY NE. ANOTHER STG SHORTWAVE TROUGH WILL DIVE INTO THE MISSOURI AND IOWA ON WEDNESDAY. THIS SYSTEM WILL BE MOISTURE STARVED...BUT GIVEN THE COLD POOL ALOFT...CANNOT RULE OUT A VFR SHOWER. OTHERWISE...INTERMITTENT VFR SC/AC DECK IS EXPECTED WITH GUSTY NW WINDS...ESPECIALLY DURING THE AFTN HOURS. DB && .EAX WATCHES/WARNINGS/ADVISORIES... MO...NONE. KS...NONE. && $$