FXUS63 KOAX 202041
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
341 PM CDT WED APR 20 2011
.SHORT TERM...TONIGHT
GOING FORECAST LOOKS IN PRETTY GOOD SHAPE. HOWEVER...HAVE DECIDED TO
BUMP POPS UP TO CATEGORICAL ON WRN CWA PERIPHERY AFT MIDNIGHT.
CONFIDENCE HIGH AT THIS POINT GIVEN GOOD MODEL CONSISTENCY. SFC HIGH
PROGGED TO SLIDE TO THE MID MS VLY THIS EVENING ALLOWING INFLUX OF
LLVL MOIST INTO THE PLAINS. UPPER IMPULSES WILL MAKE MODEST
CONTRIBUTION TO FORCING...BUT PREDOMINATE MECHANISM WILL BE
IMPRESSIVE 295-300K UPGLIDE/MOIST ADVECTION. FOR LOWS USED A BLEND
BETWEEN WARMER MET AND COOLER MAV...THUS LOW 30S NORTH AND AROUND 40
SOUTH.
DEE
.LONG TERM...TOMORROW THROUGH WEDNESDAY
MAIN FORECAST CONCERNS ARE INTERMITTENT PRECIP CHANCES UNDER AN
ACTIVE PATTERN...WITH PARTICULAR ATTENTION ON FRIDAY AND MONDAY.
WEST-SOUTHWESTERLY UPPER-LEVEL FLOW WILL DOMINATE THROUGH EARLY NEXT
WEEK...WITH WEAKER WAVES EJECTING THROUGH THE FLOW BEFORE THE MAIN
UPPER-LEVEL TROUGH PUSHES OUT OF THE ROCKIES AND INTO THE PLAINS
EARLY NEXT WEEK. WARM AIR ADVECTION TONIGHT THROUGH TOMORROW WILL
PUSH UP TEMPS INTO MORE MILD READINGS. PRECIP SHOULD SLIDE INTO THE
WESTERN CWA BY MORNING...WITH MAIN PRECIP AREA MOVING THROUGH THE
NORTHERN CWA THROUGH THE MORNING HOURS. DOES LOOK LIKE THE MORNING
RAIN WILL MISS A GOOD PART OF THE CWA...PARTICULARLY SOUTH OF I-80.
MEANWHILE...RAIN WILL SPREAD NORTHWARD OUT OF KANSAS DURING THE
AFTERNOON...AFFECTING MAINLY THE SOUTHEASTERN CWA DURING THE
AFTERNOON AND EVENING HOURS. THUS...THINK MIDDLE CWA MAY MISS OUT
ON THE BULK OF THE PRECIP...AND HAVE KEPT LOWER PRECIP CHANCES IN
THE CENTRAL CWA...ESPECIALLY IN THE MORNING.
LARGER AREA OF SHOWERS AND THUNDERSTORMS SHOULD DEVELOP TOMORROW
NIGHT IN WESTERN NEBRASKA AND KANSAS...SPREADING EASTWARD ACROSS THE
CWA THROUGH FRIDAY MORNING. WITH MID-LEVEL WARM FRONT EXTENDING
FROM KANSAS INTO MISSOURI...THINK THUNDER WILL BE MORE LIMITED AS
INSTABILITY IS LARGELY SHUNTED SOUTH. BEST POTENTIAL FOR WIDESPREAD
RAIN IS FROM LATE THURSDAY NIGHT THROUGH FRIDAY MORNING...AND HAVE
BUMPED UP POPS THEN. HAVE SCOOTED PRECIP OUT OF THE AREA A LITTLE
MORE QUICKLY ON FRIDAY AS HIGH PRESSURE BUILDS IN BEHIND THE BROAD
SURFACE LOW. MID-LEVEL BAROCLINIC ZONE REMAINS SOUTH OF THE
AREA...AND TEMPS SHOULD REMAIN COOL SATURDAY BEFORE REBOUNDING ON
SUNDAY.
AS UPPER-LEVEL TROUGH MOVES OUT OF THE ROCKIES...BAROCLINIC ZONE
SHOULD RETREAT NORTHWARD TOWARD THE CWA...BRINGING ATTENDANT PRECIP
CHANCES BACK INTO THE CWA. POTENTIAL FOR RAIN AND EMBEDDED THUNDER
RAMPS UP ON SUNDAY NIGHT AND CONTINUES THROUGH MONDAY AS THE SURFACE
LOW MOVES THROUGH OR NEAR THE CWA. AGAIN...HAVE DRIED OUT
CONDITIONS A BIT MORE RAPIDLY IN WAKE OF THE SURFACE LOW...THOUGH
SINCE GFS BRINGS IN WRAP-AROUND PRECIP ON TUESDAY...DID NOT QUITE GO
DRY JUST YET. SURFACE HIGH MOVING THROUGH ON WEDNESDAY SHOULD KEEP
WEATHER QUIET...WITH REBOUNDING TEMPERATURES WEDNESDAY NIGHT AND
THURSDAY AS WARM AIR ADVECTION COMMENCES. KEPT LATE PERIODS DRY FOR
NOW AS ANY WEATHER-PRODUCING SHORTWAVES LOOK WEAK AND TRANSIENT.
MAYES
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
HIGH CONFIDENCE APPROACHING SYSTEM WILL RESULT IN DETERIORATING
CONDITIONS AT ALL TERMINALS BY 21/12Z. EXPECT QUICK CHANGE FROM VFR
TO IFR CIGS/MVFR VSBYS ALONG WITH MOD SHRA AT LEAST AT KOFK
CONTINUING UP THRU AT LEAST 21/18Z.
DEE
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$