FXUS63 KOAX 122029
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
229 PM CST SAT MAR 12 2011
.DISCUSSION...
.SHORT TERM...TONIGHT THROUGH TUESDAY
COOL SURFACE HIGH PRESSURE OVER THE DAKOTAS CONTINUES TO MOVE
SOUTH INTO THE REGION TODAY. AN AREA OF LOW CLOUDS MOVED INTO OUR
NORTHERN COUNTIES EARLY THIS MORNING AND ALTHOUGH MODEL LLVL RH
DOES NOT HAVE A GOOD HANDLE ON THIS...WE DO EXPECT THE CLOUDS TO
CONTINUE TO ADVECT SOUTH THROUGH THE OVERNIGHT AS THE SFC HIGH
MOVES SOUTH. SUNDAY SHOULD CONTINUE TO BE MOSTLY CLOUDY SO HAVE
LOWERED HIGH TEMPS A FEW DEGREES. AN APPROACHING PIECE OF UPPER
SHORTWAVE ENERGY WILL BRING ADDED CLOUDINESS TO THE AREA SUNDAY
AFTERNOON. WL CONTINUE WITH A SMALL CHANCE OF PRECIPITATION OVER
OUR WESTERN COUNTIES BEGINNING SUNDAY AFTERNOON AS THIS PIECE OF
ENERGY ROLLS ACROSS THE REGION. QPF AMOUNTS REMAIN FAIRLY LIGHT
SO EXPECTING LESS THAN A TENTH OF AN INCH OR SO OVER MUCH OF THE
WESTERN AND SOUTHERN COUNTIES.
STRONG RETURN FLOW SETS UP BY MONDAY WHICH SHOULD PUSH HIGH TEMPERATURES
INTO THE MID TO UPPER 50S. NEXT PIECE OF SHORTWAVE ENERGY WILL
QUICKLY MOVE INTO THE REGION AND PUSH A COLD FRONT THROUGH THE
AREA ON TUESDAY AFTERNOON. THERE SHOULD BE ENOUGH LIFT AND
MOISTURE ASSOCIATED WITH THE SYSTEM TO GENERATE SCATTERED RAIN
SHOWERS THROUGH THE DAY.
.LONG TERM...
TUESDAY NIGHT THROUGH SATURDAY
AT THE BEGINNING OF THIS PERIOD...THE 12Z GFS...00Z ECMWF AND THE
12Z ECMWF WERE IN FAIRLY GOOD AGREEMENT WITH THE 500 MB PATTERN UP
UNTIL ABOUT DAY 7. A SHORTWAVE TROUGH SHOULD BE JUST EAST OF OUR
AREA...WITH A RIDGE OVER THE ROCKIES AND A TROUGH IN THE EASTERN
PACIFIC. RIDGE SHOULD BUILD QUICKLY EASTWARD...WITH SOUTHWESTERLY
MID LEVEL FLOW DEVELOPING FOR OUR AREA BY WEDNESDAY NIGHT/THURSDAY.
THE FLOW THEN FLATTENS A BIT AND A WEAK SHORTWAVE RIDGE DEVELOPS
OVER THE NORTHERN AND CENTRAL PLAINS BY SATURDAY. DETAILS WITH
PATTERN FARTHER WEST IS NOT AS CLEAR.
WILL INCLUDE A SLIGHT CHANCE OF SHOWERS FOR WEDNESDAY NIGHT AND
THURSDAY MORNING ALONG AND AHEAD OF COLD FRONT THAT WILL MOVE
THROUGH. THEN HIGH PRESSURE WILL BUILD INTO THE AREA. MID LEVEL
FORCING COULD BE STRONG ENOUGH TO GENERATE SOME SHOWERS OVER THE
SOUTHERN PARTS OF SOUTHEAST NEBRASKA AND SOUTHWEST IOWA FRIDAY...
SO INCLUDED A SLIGHT CHANCE NEAR THE KANSAS AND MISSOURI BORDERS.
ISENTROPIC LIFT STRENGTHENS AS LOW PRESSURE STARTS TO ORGANIZE IN
WYOMING AND COLORADO FRIDAY NIGHT. THE LIFT AND MOISTURE RETURN
SEEMED HIGH ENOUGH TO INCLUDE A SMALL CHANCE FOR SHOWERS ON
SATURDAY. EXPECT THAT THE PRECIPITATION WILL BE ALL LIQUID BASED
ON THERMAL PROFILES.
LATEST AFWA ENSEMBLE PROBABILITIES SUPPORT ALL THREE CHANCES FOR
PRECIPITATION IN THE 4 TO 7 DAY PERIOD.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
ALTHOUGH SURFACE HIGH PRESSURE WILL BUILD INTO MINNESOTA AND
IOWA...A COUPLE OF SHORTWAVE TROUGHS WILL MOVE THROUGH THE REGION. A
BAND OF LOW LEVEL MOISTURE WILL AFFECT KOFK/KOMA AND THE TAFS WILL
BE ON THE EDGE OF THIS MOISTURE WITH VARIABLE VFR/MVFR CONDITIONS.
FARTHER SOUTH...KLNK WILL BE AFFECTED INITIALLY BY HIGH
CLOUDS...THEN MID CLDS...AROUND FLIGHT LEVEL 10K FEET INTO SUNDAY.
STRONGER WINDS ALOFT WILL MIX DOWN WITH NORTHWEST WINDS AT TIMES 15
TO 20KTS AT KOFK AND KOMA THROUGH MID AFTERNOON. THESE WINDS WILL
GRADUALLY WEAKEN DURING THE AFTERNOON AS THESE STRONGER WINDS
DIMINISH. TONIGHT...NORTH OR NORTHEAST SURFACE WINDS WILL DECREASE
TO LESS THAN 10KTS AT ALL SITES.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
KERN/MILLER/ZAPOTOCNY