000
FXUS63 KEAX 280347
AFDEAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE KANSAS CITY/PLEASANT HILL MO
947 PM CST MON DEC 27 2010
...UPDATED AVIATION DISCUSSION...
.DISCUSSION...
SHORT TERM (TONIGHT-WED)...
MAIN CONCERNS IN THE SHORT TERM DEAL WITH CLOUDS/FOG TONIGHT AND
INCREASING TEMPS/PRECIP CHCS BY WED. EARLY THIS AFTN...SNOW CLEAR
AREAS OF WESTERN MO AND EASTERN KS WERE WARMING WELL INTO THE 30S AS
LOW-LVL WAA AHEAD OF WEAK MID-LVL SHORTWAVE MOVES THROUGH THE AREA.
LINGERING STRATUS AND SNOW COVER CONTINUES TO HOLD DOWN MAX TEMPS IN
THE NORTHEASTERN HALF OF THE CWA WITH MOST AREAS STUCK IN THE LOWER
TO MID 20S.
FOR TONIGHT...MODELS ADVERTISE THIS COMPACT S/W CROSSING THE CWA
HOWEVER LEAVING A WEAK SFC TROUGH OVER THE CWA. MODELS HAVE BEEN
POOR RESOLVING THE BOUNDARY LAYER MOISTURE OVER THE AREA THE PAST
FEW DAYS AND THINK THIS IS THE CASE ONCE AGAIN. DO NOT EXPECT THE
STRATUS TO DISSOLVE OVER NORTHERN MO THIS AFTN AND WITH ADDITIONAL
STRATUS MOVING IN FROM THE WEST...REDEVELOPMENT OF FOG/LOW CIGS
COULD BE POSSIBLE LATER THIS EVE. SOME OF THE 18Z GUIDANCE AS WELL
AS HRRR AND VSREF GUIDANCE NOW ARE BEGINNING TO SUPPORT THIS IDEA AS
WELL. THE MOST FAVORED AREAS FOR FOG DEVELOPMENT WILL BE OVER THE
SNOW PACK AND HAVE INCREASED FOG WORDING IN THOSE AREAS.
TUESDAY...DEPENDING ON CLOUD COVER TEMPERATURES SHOULD CLIMB WARMER
THAN THOSE OF TODAY IN MOST AREAS. HOWEVER...LOW-LVL SFC TROUGHING
SHOULD REMAIN IN THE AREA KEEPING MIXING TO A MINIMUM. IT COULD
TAKE A BIT OF TIME FOR STRATUS TO BREAK UP ESPECIALLY OVER THE SNOW
COVER AND HAVE LIMITED TEMPS IN THOSE AREAS AGAIN.
TUE NIGHT AND WED....DISORGANIZED UPR S/W OVER THE SOUTHWESTERN
CONUS WILL APPROACH THE AREA. THIS SHORTWAVE WILL PICKUP GOM
MOISTURE EVIDENT IN SERN TX THIS AFTERNOON AND PULL IT NORTH TO THE
CWA. WHILE THE BEST UPR DYNAMICS REMAIN WELL SOUTH OF THE CWA...LOW
LVL MOISTURE SHOULD BE PULLED FAR ENOUGH TO THE NNW TO INDUCE WIDELY
SCT SHRA OR PERHAPS DRIZZLE FOR WEDNESDAY. THE INITIAL S/W WILL MOVE
EAST OF THE CWA WED NIGHT...BUT MOISTURE SHOULD REMAIN TRAPPED IN
THE LOW-LVLS WITH WIDESPREAD STRATUS/FOG/DRIZZLE POSSIBLE.
DUX
MEDIUM RANGE (THU-MON)...
MAIN FOCUS FOR THIS PERIOD WILL BE THE PRECIP CHANCES HEADING INTO
NEW YEARS EVE AS A POTENT UPPER LEVEL TROUGH DIGS SOUTHWARD ACROSS
THE WESTERN HALF OF THE CONUS.
FOR THURSDAY...MODELS AGREE THAT THE UPPER LEVEL TROUGH WILL CONTINUE
TO DIVE DEEPER SOUTH ACROSS THE ROCKY MOUNTAIN REGION. A STRONG 50KT
LLJ WILL SURGE INTO THE REGION THU INTO FRI AHEAD OF THIS
SYSTEM...RESULTING IN A CHANCE FOR SOME RAIN SHOWERS AS MOISTURE
GETS ADVECTED NORTHWARD INTO THE AREA. WITH THE STRONG SOUTHERLY
FLOW FROM THE LLJ PREVAILING THU INTO THU NIGHT AND THE ASSOCIATED
WARM FRONT LIFTING NORTHWARD OVER THE REGION THROUGH THE DAY...MILD
CONDITIONS ARE EXPECTED WITH TEMPS RISING TO 15F TO 20F DEGREES
ABOVE SEASONAL NORMALS.
CONDITIONS WILL START TO CHANGE BY FRIDAY...AS THE ASSOCIATED COLD
FRONT PUSHES EASTWARD INTO THE CENTRAL PLAINS. STILL SOME
DISCREPANCY AMONGST THE MODELS REGARDING THE LOCATION AND TRACKING
OF THE SFC LOW ON FRI. GFS STILL SUGGESTING A BIT MORE PROGRESSIVE
SOLUTION THAN THE ECMWF...BUT IN GENERAL THEY SHOW THE COLD FRONT
MOVING FROM WEST TO EAST OVER THE CWA BEGINNING FRI MORNING...AND BE
EAST OF THE AREA BY FRI EVENING. WITH THE FRONTAL PASSAGE...WINDS
WILL SHIFT FROM THE S TO NW AND TEMPERATURES WILL TAKE A NOSE DIVE
INTO THE TEENS AND 20S BY FRI NIGHT. LIGHT RAIN...ALONG WITH THE
CHANCE FOR SOME ISOLATED THUNDER...WILL SPREAD ACROSS THE REGION THU
NIGHT INTO FRI. HOWEVER...AS THE COLD FRONT APPROACHES THE CWA'S NW
CORNER FRI MORNING AND PROGRESSES EASTWARD THROUGH THE
AFTERNOON...WE CAN EXPECT THE PRECIP TO TRANSITION OVER TO SNOW
ALONG AND BEHIND THE FRONT.
THIS STORM SYSTEM WILL BE OUT OF THE AREA BY SAT MORNING...BUT TEMPS
WILL REMAIN CHILLY AS WINDS WILL BE OUT OF THE WNW WITH THE WEST
SIDE OF THE UPPER LEVEL TROUGH STILL SCOOTING ACROSS THE REGION
DURING THE DAY. FOR THE REMAINDER OF THE PERIOD...CONDITIONS WILL BE
DRY WITH NEAR NORMAL TEMPERATURES AS A MORE ZONAL FLOW TAKES SHAPE
OVER THE CENTRAL CONUS.
ACH
&&
.AVIATION...
FOR THE 06Z TAFS...WARMER AND A LITTLE DRIER S/SW BOUNDARY LAYER FLOW
HAS SHIFTED THE MVFR/IFR STRATUS DECK WELL TO THE NE OF THE
TERMINALS. CANNOT RULE OUT A BRIEF PERIOD OF MVFR LATE TONIGHT AS A
WEAK SFC TROUGH APPROACHES...OTHERWISE VFR CONDITIONS WILL PREVAIL
THROUGH THE PERIOD.
DB
&&
.EAX WATCHES/WARNINGS/ADVISORIES...
MO...NONE.
KS...NONE.
&&
$$
