000
FXUS63 KOAX 201137
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
637 AM CDT MON MAY 20 2013

.AVIATION...
12Z TAFS FOR KOMA...KLNK...AND KOFK.

A SWATH OF MVFR CEILINGS MAY BRUSH ANY OF THE TAF SITES THIS
MORNING...WITH THE HIGHEST LIKELIHOOD AT KOMA. THE LOWER CEILINGS
WILL BREAK BY MID-MORNING...WITH SCT TO BKN MID-LEVEL CLOUDS
THROUGH THE REST OF THE DAY. HAVE INCLUDED A TEMPO MENTION AT
KOMA/KLNK FOR SHOWERS THIS AFTERNOON...AND WHILE CONFIDENCE IN
COVERAGE IS TOO LOW TO MENTION...WOULD NOT BE SURPRISED BY THUNDER
WITH THESE SHOWERS. HAVE KEPT VFR CEILINGS OVERNIGHT...THOUGH
WORTH NOTING THAT MODELS HINT AT MVFR CEILINGS AGAIN LATE IN THE
PERIOD. WINDS WILL BECOME SOUTHWESTERLY AND INCREASE BY LATE
MORNING...THEN DIMINISH AFTER SUNSET.

MAYES

&&

.PREV DISCUSSION... /ISSUED 323 AM CDT MON MAY 20 2013/

DISCUSSION...

THE UPPER LEVEL LOW CURRENTLY CENTERED OVER NE NEB AND ERN SD WILL
CONTINUE TO BE THE MAIN FORECAST ISSUE THROUGH THE SHORT TERM.
BROAD Q-G FORCING FOR ASCENT UNDER THE UPPER LEVEL LOW WAS
LEADING TO SCATTERED SHOWERS OVER CENTRAL AND NE NEB EARLY THIS
MORNING. THIS SHOULD CONT IN NE NEB WITH MOST OF THE CENTRAL AND
SOUTHERN CWA DRY THIS MORNING. SOME SUN IS EXPECTED TODAY OVER
THIS AREA OF THE CWA /SW IA AND SE NEB/ THAT WILL STEEPEN LOW
LEVEL LAPSE RATES. GIVEN THE RESIDUAL LOW LEVEL MOISTURE IN PLACE
ACROSS THIS AREA AND THE COLD MID LEVEL TEMPERATURES UNDER THE
UPPER LEVEL LOW...THE ATMOSPHERE SHOULD BECOME WEAKLY UNSTABLE
THIS AFTERNOON WITH AROUND 400-600 J/KG OF SBCAPE OVER THE CNTRL
AND SRN CWA. THIS SHOULD LEAD TO SCATTERED AFTERNOON SHOWERS AND
ISO THUNDERSTORMS ACROSS THE FA. SEVERE WEATHER GENERALLY SEEMS
UNLIKELY...BUT WITH THE STEEP MID LEVEL LAPSE RATES AND MODERATE
SHEAR SOME HAIL SEEMS POSSIBLE IF SUFFICIENT HEATING CAN TAKE
PLACE THROUGH THE MORNING. OTHERWISE THE SHOWERS AND ISO TSRA
SHOULD DIMINISH QUICKLY THIS EVENING WITH THE LOSS OF DAYTIME
HEATING. THE SETUP FOR TUESDAY ISN`T AS FAVORABLE FOR AFTERNOON
TSRA AS THE LOW LEVEL RESIDUAL MOISTURE GETS DISPLACED TO THE EAST
AS CAA MOVES THROUGH THE FA BEHIND A SFC CDFNT ON MON NIGHT. THIS
WILL LEAD TO SEASONABLY COOL TEMPERATURES FOR TUE/WED. WE MAY SEE
AN ISO SHOWER IN THE NRN FA UNDER THE UPPER LEVEL LOW...BUT THESE
WILL BE PRETTY ISOLATED.

THE LOW FINALLY STARTS TO SHIFT EAST ON THU WITH DRY WEATHER
RETURNING...BUT THIS WILL ONLY BE FOR A SHORT TIME AS LONGER RANGE
MODELS ARE FAIRLY CONSISTENT IN BRINGING IN A TROUGH TO THE
WESTERN US WITH WAA TYPE PRECIP DEVELOPING STARTING ON FRI AND
INTO NEXT WEEKEND. WITH THE RETURN FLOW TEMPERATURES WILL ALSO BE
RETURNING TO NEAR NORMAL AS WELL.

BOUSTEAD

&&

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

$$

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