FXUS63 KOAX 050821
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
321 AM CDT THU MAY 5 2011
.DISCUSSION...
PATTERN CHANGE WILL BRING MORE UNSETTLED WEATHER TO THE AREA THROUGH
THE WEEKEND AND INTO NEXT WEEK. SUBJECTIVE 00Z UPPER AIR ANALYSIS
INDICATES WAVY FLOW ACROSS THE CONUS...WITH RIDGE IN THE
WEST...TROUGH FROM THE WESTERN DAKOTAS INTO THE 4 CORNERS...RIDGE IN
THE UPPER MISSISSIPPI RIVER VALLEY...AND TROUGH IN THE
MID-ATLANTIC. SCANT MOISTURE EXISTS IN THE CONUS...WITH 1-2C 850MB
DEWPOINTS IN SD/NEB/MO THE HIGHEST ANYWHERE OUTSIDE OF FL. 850MB
COLD FRONT AT 00Z EXTENDED FROM EASTERN SD THROUGH CENTRAL NEB AND
WESTERN KS INTO NM AND WAS THE SOURCE OF THE MEAGER MOISTURE
POOLING...WITH A FEW SHOWERS MOVING ACROSS NEB/KS THIS MORNING.
SURFACE COLD FRONT AT 07Z EXTENDED FROM 1001MB LOW IN NORTHWEST IA
THROUGH KOLU/KHJH...WITH PREFRONTAL TROUGH FURTHER AHEAD...FROM LOW
THROUGH KAFK/KLWC/KPTT AND TOWARD SECOND SURFACE LOW IN THE TX
PANHANDLE.
MAIN FORECAST CONCERNS ARE CHANCES FOR SHOWERS/THUNDER PERIODICALLY
THROUGH THE NEXT SEVERAL DAYS. DEEP UPPER LOW WILL DIG INTO THE
WESTERN US THROUGH THE WEEKEND...WITH SOUTHWESTERLY FLOW DEVELOPING
IN THE PLAINS INTO EARLY NEXT WEEK. TEMPERATURES WILL BE SLIGHTLY
COOLER TODAY...THOUGH NORTHWESTERLY WINDS AND DRY AIRMASS WILL STILL
ALLOW PLENTY OF MIXING. CONTINUED SLIGHT CHANCE POPS FOR POSSIBLE
SHOWER DEVELOPMENT THIS AFTERNOON AS UPPER-LEVEL COLD AIR POCKET
ALLOWS INCREASING LAPSE RATES/DECREASED LI. THINK MOISTURE IS TOO
MEAGER FOR ANYTHING MORE THAN A FEW ISOLATED SHOWERS THAT WILL DIE
QUICKLY AFTER SUNSET...AND HAVE KEPT POPS OUT AFTER 00Z.
SOUTHERLY FLOW RETURNS ON FRIDAY...WITH STRONG WARM AIR ADVECTION
THROUGH THE DAY. MODELS DO BRING AN AXIS OF INCREASING MOISTURE
THROUGH TX AND INTO SOUTHEAST KS THROUGH THE EVENING. MEANWHILE...
AN UPPER-LEVEL WAVE IS PROGGED TO MOVE THROUGH THE NORTHERN
PLAINS...WITH AN ATTENDANT SURFACE LOW MOVING FROM THE DAKOTAS INTO
IA. WITH MOISTURE AXIS SOUTH AND SOUTHEAST OF THE CWA...AND LOW
MOVING FROM NORTH TO EAST OF THE CWA...BELIEVE AREA WILL REMAIN DRY
ON FRIDAY AS SHOWERS/THUNDER DEVELOP EAST/NORTHEAST/SOUTHEAST.
MODEL CONSENSUS NOW IS TO KEEP PRECIP DEVELOPMENT EAST OF THE CWA AS
WELL...AND HAVE PULLED OUT POPS FOR FRIDAY/FRIDAY NIGHT. COLD FRONT
ASSOCIATED WITH LOW WILL DO LITTLE TO CHANGE MID-LEVEL
TEMPERATURES...BUT INCREASED CLOUDINESS AND MOISTURE MAY BEGIN TO
LIMIT WARMING A BIT...AND HAVE NUDGED TEMPS DOWN SATURDAY JUST A
TOUCH. AS WESTERN LOW DIGS IN AND SURFACE LOW DEVELOPS IN WESTERN
KS...A WARM FRONT IS PROGGED TO DEVELOP BY SUNDAY AND LIFT NORTHWARD
IN OR NEAR THE CWA. WOULD EXPECT CONVECTIVE DEVELOPMENT ALONG THIS
FRONT ON SUNDAY...AND NOCTURNAL CONVECTION ALONG THE WARM FRONT ON
SUNDAY NIGHT...AS MOISTURE CONTINUES TO INCREASE THROUGH THE
WEEKEND...BUT HAVE LOW CONFIDENCE ON LOCATION AS FEATURES ARE NOT
YET WELL RESOLVED BY MODELS WITH MUCH AGREEMENT. MADE FEW CHANGES
TO POPS OVERALL...BUT WILL HIGHLIGHT POTENTIAL ON SUNDAY/SUNDAY
NIGHT MORE SPECIFICALLY IN HWO.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
COLD FRONT MOVING THROUGH THE REGION WILL BRING GUSTY NORTHWEST
WINDS TO KOMA/KLNK THROUGH 08-10Z...THEN AGAIN TO ALL 3 TAF SITES BY
14-16Z. SCATTERED RAIN SHOWERS SHOULD BE EAST OF THE TAF SITES BY
ABOUT 07-08Z...BUT COULD REDEVELOP THIS AFTERNOON AT ALL TAF SITES
FROM 18-24Z. BY 06/01Z...HIGH PRESSURE BUILDS OVERHEAD RESULTING IN
CLEAR SKIES AND LIGHT AND VARIABLE WINDS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
MAYES/DEWALD