000
FXUS63 KOAX 120752
AFDOAX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
252 AM CDT SUN MAY 12 2013

.DISCUSSION...

SURFACE HIGH PRESSURE RIDGE OVERHEAD HAS ALLOWED WINDS TO BECOME
CALM IN MOST AREAS...WITH TEMPERATURES MOSTLY IN THE LOWER TO MID
30S THIS MORNING. HOWEVER...TEMPS AT FAVORED LOCATIONS BOTH ALONG
AND IN THE MISSOURI RIVER VALLEY WERE STILL IN THE LOWER 40S. AS
EXPECTED...SOME CIRRUS IS STARTING TO MOVE INTO SOUTHEAST
NEBRASKA THIS MORNING...WHICH WILL PROBABLY STOP ANY TEMPERATURE
FALL IN THAT LOCATION. WILL LEAVE EXISTING FROST ADVISORY IN PLACE
THIS MORNING WITH NO CHANGES. RADAR WAS ALSO SHOWING A FEW VERY
LIGHT RETURNS IN CENTRAL NEBRASKA...ALTHOUGH THIS IS LIKELY
COINCIDENT WITH THE MID CLOUD BASES AT 9-11 FEET AND DOUBTFUL IF
ANYTHING WOULD BE REACHING THE GROUND...THUS WILL MAINTAIN A DRY
FORECAST. OTHERWISE...IT SHOULD BE A VERY DELIGHTFUL DAY WITH MUCH
LIGHTER WINDS THAN YESTERDAY...AND COMFORTABLE TEMPS IN THE MID T
UPPER 60S.

RETURN SOUTHERLY FLOW DEVELOPS ALONG WITH RIDGING ALOFT EARLY IN
THE WEEK. THIS WILL RESULT IN BREEZY CONDITIONS AGAIN MONDAY WITH
HIGHS BACK ABOVE NORMAL IN THE UPPER 70S TO MID 80S. IT SHOULD GET
EVEN WARMER ON TUESDAY AHEAD OF THE NEXT COLD FRONT THAT IS
EXPECTED TO MOVE THROUGH THE REGION. NAM/SREF ARE NOW SUGGESTING
THAT THIS FRONT MAY BE JUST A BIT QUICKER THAN PREVIOUSLY THOUGHT...
WHICH WOULD PLACE IT SOLIDLY ALONG OR JUST NORTH OF I80. ECMWF AND
GFS ARE SLIGHTLY SLOWER WITH THE FRONT FURTHER NORTH BY ABOUT 100
MILES. THIS WILL HAVE AN IMPACT ON THE FORECAST ON TIMING OF
THUNDERSTORMS THAT COULD POTENTIALLY DEVELOP IF THE NAM/SREF WERE
CORRECT. ADJUSTED TIMING A BIT OF THE FRONTAL PASSAGE...BUT NOT AS
FAST AS NAM/SREF WOULD SUGGEST...BUT WILL HAVE TO CONTINUE TO
MONITOR THIS WITH SUBSEQUENT MODEL RUNS.

BEYOND THEN...NOT GREAT CONFIDENCE IN FORECAST EVOLUTION
EITHER...WITH GFS SUGGESTING THE FRONT CONTINUES TO MAKE PROGRESS
SOUTHWARD AWAY FROM THE AREA WEDNESDAY NIGHT...BUT THE ECMWF HANGS
UP IN SOUTHEAST NEBRASKA AND LINGERS A PRECIP THREAT A LITTLE
LONGER. VERY WEAK ZONAL FLOW PREVAILS AFTER THAT WITH POSSIBLY
ANOTHER SUBTLE WAVE MOVING THROUGH THURSDAY NIGHT/FRIDAY...THEN
ANOTHER FRIDAY NIGHT/SATURDAY.

DEWALD

&&

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

VFR CONDITIONS WILL PREVAIL THROUGH SUNDAY EVENING. LIGHT WINDS
WILL BECOME SOUTH OR SOUTHEAST IN THE 16Z TO 21Z TIMEFRAME...BUT
SHOULD REMAIN AT OR BELOW 10KT. SCATTERED TO BROKEN HIGH CLOUDS
ARE POSSIBLE AT TIMES.

DERGAN

&&

.OAX WATCHES/WARNINGS/ADVISORIES...
NE...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR NEZ011-012-
     015>018-030>034-042>045-050>053-065>068-078-088>093.

IA...FROST ADVISORY UNTIL 9 AM CDT THIS MORNING FOR IAZ043-055-056-
     069-079-080-090-091.

&&

$$