FXUS63 KOAX 230827
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
327 AM CDT THU JUN 23 2011
.DISCUSSION...
UPPER LOW...AND ITS COOL/SHOWERY/CLOUDY INFLUENCE...IS FINALLY
DEPARTING THE AREA. SUBJECTIVE 00Z UPPER AIR ANALYSIS INDICATES
STACKED UPPER LOW CENTERED IN WI...WITH UPPER-LEVEL RIDGING OVER THE
ROCKIES...AND A DEVELOPING LOW OFF THE PACIFIC NORTHWEST COAST.
COOL 850MB TEMPS <10C CONTINUE TO EXTEND THROUGH THE DAKOTAS INTO
EASTERN NEB/WESTERN IA...THOUGH MUCH WARMER TEMPS LURK JUST
WEST...WITH 25C AT KDDC. SURFACE RIDGING AT 07Z WAS BUILDING INTO
THE HIGH PLAINS AS 998MB LOW LINGERS IN WI...WITH PRESSURE GRADIENT
SLACKENING ACROSS THE CWA.
MAIN FORECAST CONCERN IS CONVECTIVE POTENTIAL THIS WEEKEND.
MISSOURI VALLEY AREA WILL COME UNDER THE INFLUENCE OF
SURFACE/MID-LEVEL RIDGING TODAY AND TONIGHT AS BIG UPPER LOW
CONTINUES TO SLIDE EASTWARD INTO THE GREAT LAKES. AS IT
DOES...UPPER-LEVEL RIDGE WILL BUILD INTO THE CENTRAL US...WITH
UPPER-LEVEL TROUGH DIGGING INTO THE WEST AS THE PACIFIC NORTHWEST
LOW COMES ASHORE. SKIES SHOULD CLEAR FROM WEST TO EAST TODAY AND
REMAIN MAINLY CLEAR TONIGHT. ONE MORE DAY OF COOL TEMPS IS IN STORE
FOR TODAY...GIVEN WEAK MIXING UNDER HIGH PRESSURE AND COLD POOL
STILL INFLUENCING MOST OF THE CWA. RETURN FLOW WILL PUSH MID-LEVEL
MOISTURE/WARM AIR ADVECTION INTO NEB ON FRIDAY AND IA BY FRIDAY
NIGHT. CURRENT INDICATIONS ARE THAT CONVECTIVE DEVELOPMENT DURING
THE AFTERNOON AND EVENING WILL TAKE PLACE IN WESTERN NEB. 850MB
WARM FRONT WILL LIFT INTO THE CWA FRIDAY NIGHT...WITH LOW-LEVEL JET
IMPINGING ON THE BOUNDARY THROUGH THE NIGHT. THINK CONVECTION WILL
BE ABLE TO GROW UPSCALE INTO AN MCS THAT TRACKS ALONG THAT BOUNDARY
ACROSS THE CWA...PARTICULARLY AFTER 06Z. HAVE INCREASED POPS 06-12Z
SATURDAY.
APPEARS THAT CWA WILL BE IN A BIT OF A RELOAD PATTERN ON SATURDAY AS
OVERNIGHT CONVECTION DIES AWAY/SLIDES EAST...AND THINK CWA WILL BE
MAINLY DRY DURING THE DAY ONCE THE EARLY MORNING MCS CLEARS AWAY TO
THE EAST. HAVE CUT BACK POPS DURING THE DAY AND MIGHT STILL BE TOO
HIGH. BUMPED UP TEMPS ON SATURDAY...ESPECIALLY IN NEB...GIVEN THE
MAINLY DRY DAYTIME AND WARMING MID-LEVEL TEMPS. ONCE
AGAIN...APPEARS THAT CONVECTION WILL DEVELOP IN WESTERN NEB IN THE
AFTERNOON/EVENING ON SATURDAY...AND ONCE AGAIN...AN MCS MAY MOVE
ACROSS THE CWA ON SATURDAY NIGHT AS THE 850MB BOUNDARY LINGERS IN
THE AREA. HAVE CONTINUED CHANCE TO LIKELY POPS THROUGH THE NIGHT.
PATTERN RELOADS AGAIN FOR SUNDAY AS UPPER TROUGHING LINGERS IN THE
WESTERN US AND SURFACE LOW LINGERS IN WESTERN KS. THOUGH
UNCERTAINTY INCREASES THROUGH THE WEEKEND DUE TO THE INTERPLAY OF
CONVECTIVE OUTFLOW...STABILIZATION...AND MESOSCALE BOUNDARIES...ONCE
AGAIN IT APPEARS THAT THE DAYTIME SUNDAY SHOULD BE DRY IN THE CWA AS
MORNING MCS MOVES EAST...WITH AFTERNOON AND EVENING CONVECTIVE
DEVELOPMENT IN WESTERN AND CENTRAL NEB AND MCS MOVING ACROSS THE CWA
SUNDAY NIGHT. ALSO BUMPED UP TEMPERATURES ON SUNDAY...WITH SIMILAR
REASONING TO SATURDAY.
MADE NO CHANGES BEYOND SUNDAY NIGHT.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
LOW CLOUDS WILL CONTINUE TO PIVOT DOWN MISSOURI RIVER VALLEY THROUGH
THIS MORNING. THIS COULD PROVIDE TEMPORARY MVFR CEILINGS TO KOMA
AND POSSIBLY KOFK...ESPECIALLY IF SOME DEVELOPMENT WESTWARD OCCURS
WITH A LITTLE HEATING THIS MORNING. HOWEVER...IN GENERAL CONDITIONS
SHOULD BE VFR. NW SURFACE WINDS SHOULD INCREASE WITH HEATING THIS
MORNING...MAINLY AT KOMA AND KOFK.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
MAYES/CHERMOK