FXUS63 KOAX 170852
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
352 AM CDT TUE MAY 17 2011
.DISCUSSION...
AFTER TODAY...FORECAST CONCERNS WILL BE TIMING OF PRECIPITATION
FOR WEDNESDAY AND WEDNESDAY NIGHT AND CONTINUED PRECIPITATION INTO
THE WEEKEND.
WE ARE STARTING OUT WITH A REX BLOCKING PATTERN OVER THE U.S.
LARGE CLOSED MID TROPOSPHERIC LOW PRESSURE SYSTEMS ARE OVER THE
WESTERN AND EASTERN PORTIONS OF THE U.S...WITH A NARROW RIDGE OF
HIGH PRESSURE IN THE MIDDLE. THIS PATTERN WILL GIVE US ANOTHER
PLEASANT DAY WILL WITH A LITTLE STRONGER WINDS. EXPECT MORE CIRRUS
TODAY AS THE MID LEVEL RIDGE GETS PINCHED OFF AND SOUTHEAST WINDS
TO STRENGTHEN TO 10 TO 20 MPH AS SURFACE HIGH PRESSURE REMAINS IN
PLACE AND SURFACE LOW PRESSURE DEEPENS OVER THE LEE OF THE
ROCKIES. TEMPERATURES TODAY SHOULD TOP OUT IN THE UPPER 60S TO
AROUND 70.
AS THE FIRST CENTER OF THE CLOSED H5 LOW MOVES ACROSS NEVADA INTO
UTAH...THE SHORT RANGE MODELS DIFFER ON HOW MUCH PRECIPITATION
WILL DEVELOP. THE NAM IS DRY...THE GFS IS WET WITH THREE QUARTERS
OF AN INCH OF RAIN IN THE NORTH DURING THE DAY...AND THE ECMWF IS
MORE OF A COMPROMISE WITH A TENTH OF AN INCH IN THE WEST IN THE
MORNING AND A TENTH OF AN INCH IN THE NORTH IN THE AFTERNOON. THE
UKMET ALSO BRINGS SOME PRECIPITATION TO THE BORDER THEN DISSIPATES
IT HAS IT WEAKENS AND MOVES INTO THE DRIER AIR AND THIS IS SIMILAR
TO THE GEM. THUS...WILL FOLLOW THE SLOWER COMPROMISE AND BRINGS
SOME POPS INTO THE WEST...AND WEAKEN IT AS IT MOVES EAST ACRS THE
FORECAST AREA. HIGH TEMPERATURES WEDNESDAY SHOULD BE HELD TO THE
UPR 50S AND LOWER 60S IN THE WEST DUE TO THE CLOUDS AND THE 60S IN
THE EAST.
WEDNESDAY NIGHT...THE H85 FLOW STRENGTHENS TO 55KTS OVER KANSAS
AND DEEPER MOISTURE IS TRANSPORTED NORTH INTO THE FCST
AREA...MEANWHILE LARGER SCALE LIFT IS OCCURRING WITH THE CLOSED
LOW APPROACHING FROM THE WEST AND STRONG ISENTROPIC LIFT FROM
KANSAS INTO NEBRASKA. THE BAND OF PRECIPITATION SHOULD BECOME MORE
WIDESPREAD INTO THE FORECAST AREA OVERNIGHT INTO THURSDAY AND
THURSDAY NIGHT. IN ADDITION...EAST SOUTHEAST WIND SHOULD BECOME QUITE
STRONG AT 20 TO 30MPH. LIFTED INDICES DROP BELOW ZERO THURSDAY
AFTERNOON IN THE SOUTH AND NEGATIVES LI/S SPREAD ACROSS THE
FORECAST AREA OVERNIGHT AND WILL MENTION THUNDERSTORMS. LOW LEVEL
AND DEEP LAYER SHEAR ARE SUFFICIENT ALONG WITH INCREASING
INSTABILITY FOR SEVERE STORMS LATER THURSDAY AFTERNOON THRU
FRIDAY. AT THIS TIME THE STORM PREDICTION CENTER SLIGHT RISK IS
JUST TO THE SOUTH OF THE FORECAST AREA...WHERE INSTABILITY
PARAMETERS ARE A BIT BETTER. WITH THE TRAINING OF THE STORMS SOME
1 TO 3 INCH RAINS WILL BE POSSIBLE THURSDAY THROUGH FRIDAY NIGHT.
FOR THE EXTENDED...THURSDAY NIGHT AND BEYOND...THE GFS IS FASTER
WITH THE BULK OF THE PRECIPITATION ENDING BY EARLY FRIDAY NIGHT
WITH SOME WRAP AROUND PRECIP POSSIBLE SATURDAY THEN THE NEXT STORM
SYSTEM BRINGS MORE RAIN SUNDAY NIGHT AND MONDAY. THE ECMWF LINGERS
MORE PRECIP FRIDAY NIGHT AND SATURDAY MORNING AND ALSO HAS A
SHORTWAVE TROF IN SOUTHWEST FLOW ALOFT SUNDAY NIGHT AND MONDAY.
CURRENT FORECAST HAS THE RAIN COVERED FOR THE WEEKEND INTO EARLY
NEXT WEEK.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
VFR CONDITIONS SHOULD CONTINUE AT TAF SITES THROUGH 18/06Z. SERLY
SURFACE WINDS WILL INCREASE BY TUESDAY AFTERNOON...GENERALLY INTO
THE 10-20KT RANGE. OTHERWISE MAINLY JUST HIGH CLOUDS ARE EXPECTED
THROUGH 18Z/06Z ALTHOUGH CEILINGS ABOVE 3000K FT COULD APPROACH
KOFK/KLNK JUST AFTER THAT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
ZAPOTOCNY/CHERMOK