507 
FXUS63 KOAX 122042
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
342 PM CDT THU SEP 12 2013

.DISCUSSION...

SURFACE HIGH PRESSURE RIDGE AXIS CENTERED FROM WRN ND INTO NRN NEB
WILL DEVELOP SEWD CROSSING THE CWA OVER THE NEXT 24 HOURS OR SO.
THIS WILL LEAD TO LITTLE IN THE WAY OF SENSIBLE WX FOR OUR CWA
WITH CLEAR SKIES...LIGHT WINDS...AND COOL TEMPERATURES. THE REX
BLOCK OVER THE WRN US WILL START TO BREAK DOWN DURING THIS TIME
AND THE WRN US UPPER LEVEL LOW WILL START TO SHIFT NEWD TOWARD THE
CNTRL AND NRN PLAINS. THE SYSTEM WILL BRING PLENTY OF MID AND
HIGH LEVEL MOISTURE TO THE AREA...BUT THE LOWER LEVEL ATMOSPHERE
WILL BE DRY WITH STRONG STATIC STABILITY. THIS WILL LIMIT THE
EFFECTIVENESS OF THE RELATIVELY WEAK FORCING WITH THIS SYSTEM AND
LIMIT THE AREAL EXTENT OF THE PRECIPITATION. POINT FORECAST
SOUNDINGS INDICATE SUFFICIENT SATURATION WILL LIKELY TAKE PLACE
WELL AFTER MIDNIGHT IN THE NRN CWA AND HAVE REMOVED FRIDAY EVENING
POPS. WILL CONT WITH SOME SCHC POPS AFTER MIDNIGHT IN THE NW.
DESPITE THE NEGATIVES WE STILL SHOULD SEE A BAND OF LIGHT RAIN
MOVE ACROSS THE FAR NRN CWA SAT MORNING GIVEN THE PERSISTENCE OF
THE ISENTROPIC LIFT ON THE 305K SFC. THUS WILL CONT WITH THE
LIKELY POPS DURING THIS TIME /GENERALLY NORTH OF HIGHWAY 20/...AND
MAINTAIN A SCHC POP DOWN TO I80 BUT THIS WILL LIKELY BE MORE
SPRINKLES OR NON-MEASURABLE SHRA. MOST OF SAT THOUGH WILL BE
MOSTLY CLOUDY...WARM...AND SEASONABLY HUMID AHEAD OF THE COLD
FRONT THAT STILL LOOKS TO MOVE THROUGH THE AREA ON SAT NIGHT.
MOISTURE WILL CONTINUE TO INCREASE SAT NIGHT NEAR THE FRONT AND
MID TROPOSPHERIC LAPSE-RATES WILL ALSO INCREASE SUFFICIENTLY TO
BRING IN A CHANCE OF SHOWERS AND ISOLATED THUNDERSTORMS TO THE
AREA. THE BEST FORCING SAT NIGHT WILL BE TO THE NORTH AND THEN
EAST OF OUR FA ASSOCIATED WITH A NRN STREAM SYSTEM DIVING INTO THE
NRN PLAINS...BUT MOISTURE AND LIFT APPEAR SUFFICIENT TO WARRANT
THE CURRENT LIKELY POPS. THE FRONT WILL CONT TO SINK SOUTH ON SUN
WITH A CHANCE OF SHOWERS ALONG THE FRONT.

THE PERIOD SUN NIGHT THROUGH TUE IS A BIT UNCLEAR AS THE GLOBAL
MODELS ARE AT ODDS AS TO HOW FAR SOUTH TO TAKE THE SAT NIGHT FRONT
AND HOW QUICKLY WAA AND ASSOCIATED ISENTROPIC LIFT WILL RETURN TO
THE AREA. THUS WE MADE VERY FEW CHANGES TO THESE PERIODS AND WILL
CONT WITH THE CHC POPS /ALTHOUGH RAIN DURING THE ENTIRE PERIOD IS
UNLIKELY/. ONCE THE WARM FRONT LIFTS TO THE NORTH...LIKELY DURING
SOMETIME ON TUE WE EXPECT A DRY AND WARMING TREND TO END THE
EXTENDED FOR WED/THU WITH TMPS GETTING BACK INTO THE MID 80S AND
DECENT DEWPOINTS RETURNING IN THE SW FLOW ALOFT. 

BOUSTEAD

&&

.AVIATION...
18Z TAFS FOR KOFK...KOMA AND KLNK.

VFR CONDITIONS ARE EXPECTED AS HIGH PRESSURE MOVES SOUTH FROM THE
NORTHERN PLAINS. NORTHEAST SURFACE WINDS WILL BECOME SOUTHEAST
THROUGH THE TAF CYCLE.

KERN

&&

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

&&

$$