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000
FXUS63 KOAX 210343
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1043 PM CDT MON MAY 20 2013

.AVIATION...
06Z TAFS FOR KOFK...KOMA AND KLNK.

EXTENSIVE LOW TO MID CLOUD DECK CONTINUES TO MOVE THROUGH BROAD
CYCLONIC FLOW INTO EASTERN NEBRASKA. THIS WILL SPREAD OVER ALL TAF
SITES OVERNIGHT WITH CIGS LIKELY GOING FROM VFR DOWN TO MVFR. A FEW
SCATTERED LIGHT RAIN SHOWERS ARE POSSIBLE BUT TOO SMALL OF A CHANCE
TO FEEL THE NEED TO INCLUDE IN THE TAFS.

KERN

&&

.PREV DISCUSSION... /ISSUED 340 PM CDT MON MAY 20 2013/

DISCUSSION...
FORECAST CONCERNS OVER THE NEXT FEW DAYS WILL MAINLY BE SPORADIC
SHOWERS...AND ISOLATED THUNDERSHOWERS THIS EVENING...THEN
TEMPERATURES.

AT 12Z A SEASONABLY STRONG H30 JET WITH 80 TO 100KT WINDS DOVE
SOUTH THROUGH UTAH ACROSS NORTHERN NEW MEXICO AND THE TEXAS
PANHANDLE AN RE-CURVES NORTHEAST ACROSS IOWA. THE FORECAST AREA IS
UNDER THE INFLUENCE OF A LARGE AREA OF CLOSED LOW PRESSURE
CENTERED OVER SOUTH DAKOTA AND NORTHERN NEBRASKA...THAT ELONGATES
BACK ACROSS COLORADO. THE H7 AND H85 WERE SIMILARLY VERTICALLY
STACKED. DECENT MOISTURE WAS NOTED PER THE 12Z KLBF RAOB TO 440MB
AND THE KOAX RAOBS TO 560MB.

BY LATE AFTERNOON AND TONIGHT...THE H5 LOW WILL REMAIN IN THE
SAME LOCATION...THEN GRADUALLY WEAKEN AND SEND SOME ENERGY AROUND
THE LOW. CONVECTIVE TEMPERATURES ARE IN THE UPPER 70S AND THERE IS
SOME MID LEVEL WARM ADVECTION THROUGH THE EVENING. THE ATMOSPHERE HAS
BECOME CONVECTIVELY UNSTABLE WITH SURFACE BASED CAPE 500-1000
J/KG. A FEW SHOWERS HAVE DEVELOPED AND SOME THUNDERSTORMS COULD
ALSO DEVELOP. ALTHOUGH THE COVERAGE MAY BE TOUGH TO PIN DOWN...THE
OPERATIONAL/EXPERIMENTAL MODELS ARE SPLIT WITH SOME DRY AND
OTHERS GENERATING SOME ISOLD TO SCATTERED PRECIP. LOOKING AT THE
NAM/HRRR/RAP/HOPWRF ENSEMBLES/4KM WRF/GFS TEND TO FOCUS THE HIGHER
PRECIP CHANCES OVER THE FAR SOUTHEAST NEB AND SOUTHWEST IOWA
COUNTIES OR IN THE NORTHWEST EARLY THIS EVENING WITH ISOLD
ELSEWHERE...WITH A GENERAL DOWNWARD TREND IN AND LOCAL PRECIP
AFTER SUNSET.

WE CONTINUE TO BE UNDER THE INFLUENCE OF CYCLONIC FLOW THROUGH
WEDNESDAY...THUS A CLOUDY AND COOLER PERIOD WITH SOME CHANCE OF
SHOWERS. ANY PRECIPITATION SHOULD BE ON THE LIGHT SIDE. HIGHS
TUESDAY AND WEDNESDAY IN THE 60S AND 70S. WE SEE A BREAK WITH
RIDGING OVER THE AREA WEDNESDAY NIGHT THROUGH THURSDAY NIGHT
HOWEVER CLOUDS WILL BE ON THE INCREASE. THE NEXT CHANCE FOR
THUNDERSTORMS WILL BE FRIDAY AND LAST INTO THE WEEKEND. THE 12Z
EURO IS A LITTLE MORE PROGRESSIVE WITH THE WEATHER AND DRIES IT
OUT BY SATURDAY AFTERNOON. SO...THE SAT AFTERNOON INTO MONDAY
FORECAST WILL LIKELY SEE SOME ADJUSTMENT AS THE LONG RANGE MODELS
COME INTO BETTER AGREEMENT.

CZ
&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&

$$