FXUS63 KOAX 242030
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
330 PM CDT TUE MAY 24 2011
.SHORT TERM...TONIGHT.
THE THUNDERSTORM COMPLEX THAT MOVED INTO THE AREA THIS MORNING AND
EARLY THIS AFTERNOON CONTINUED TO MOVE OFF TO THE EAST AND NORTHEAST.
THAT SHOULD BE OUT OF OUR AREA BY LATE AFTERNOON WITH NEW STORMS
INCREASING IN COVERAGE ACROSS KANSAS.
SURFACE LOW PRESSURE CENTER OVER THE OKLAHOMA PANHANDLE WILL TRACK
NORTHEAST AND INTENSIFY TONIGHT. MAINTAINED HIGH POPS OVERNIGHT
AND ISSUED A FLASH FLOOD WATCH INTO WEDNESDAY MORNING WITH HIGH
PRECIPITABLE WATER IN PLACE...AND FLASH FLOOD GUIDANCE OF TWO INCHES
OR LESS. RISK FOR SEVERE IS HIGHEST OVER KANSAS...MISSOURI AND
OKLAHOMA. HOWEVER WITH A FRONTAL BOUNDARY IN THE AREA AND THE LOW
LEVEL JET STRENGTHENING OVERNIGHT...LOW LEVEL SHEAR AND DEEP LAYER
SHEAR ALONG WITH STRONG DYNAMICS MAY PRODUCE SOME SEVERE STORMS
WITH HAIL AND DAMAGING WINDS. TORNADO THREAT IS MUCH HIGHER TO THE
SOUTH...BUT AN ISOLATED TORNADO IS NOT OUT OF THE QUESTION FOR PARTS
OF SOUTHEAST NEBRASKA.
.LONG TERM...WEDNESDAY THROUGH TUESDAY.
CLOSED LOW AT 500 MB SHOULD BE OVER CENTRAL KANSAS AT 12Z WEDNESDAY.
NORTHERN PARTS OF THE AREA SHOULD BE AFFECTED BY DEFORMATION ZONE AND
ISOLATED THUNDERSTORMS. SOUTHERN PARTS OF THE AREA WILL BE CLOSER TO
THE COLD POCKET ALOFT...AND WITH STEEPER LAPSE RATES...THUNDERSTORMS
ARE MORE LIKELY. HEAVIEST RAIN IN THE MORNING SHOULD BE ACROSS
NORTHEAST NEBRASKA...WITH MODERATE TO LOCALLY HEAVY RAIN POSSIBLE FOR
ALL OF THE AREA IN THE AFTERNOON. HAVE NORTHEAST WINDS CLOSE TO OR
AROUND WIND ADVISORY CRITERIA FOR WEDNESDAY ACROSS NORTHEAST NEBRASKA
BUT DID NOT ISSUE AN ADVISORY JUST YET. OVERNIGHT CAN TAKE A LOOK AT
THAT. FEEL THERE WILL STILL BE A SLIGHT RISK OF SEVERE STORMS IN
SOUTHEAST NEBRASKA AND SOUTHWEST IOWA ON WEDNESDAY WITH THE 12Z GFS
SHOWING LIFTED INDICES -2 TO -6 AT 18Z WEDNESDAY AND MIXED LAYER CAPE
VALUES 1500-2000 J/KG.
PRECIPITATION CHANCES SHOULD DECREASE FROM NORTHWEST TO SOUTHEAST
WEDNESDAY NIGHT...AS THE SYSTEM PULLS EAST AND AMOUNTS WILL BE MOSTLY
UNDER TWO TENTHS OF AN INCH IN THAT PERIOD. A WEAK RIDGE OF HIGH
PRESSURE SHOULD BRING DRY CONDITIONS FOR THURSDAY. THAT RIDGE WILL
MOVE OFF TO THE EAST THURSDAY NIGHT. RETURN OF LOW LEVEL MOISTURE AND
APPROACHING SHORTWAVE TROUGH SHOULD BRING SHOWERS AND SCATTERED
THUNDERSTORMS ACROSS THE WESTERN PARTS OF THE AREA LATE THURSDAY
NIGHT AND THIS SHOULD LAST INTO FRIDAY. NEXT WAVE WILL BE DIGGING
INTO THE WESTERN UNITED STATES WITH A CLOSED LOW DEVELOPING OVER
NEVADA OR UTAH SUNDAY. THE GFS AND ECMWF LARGE SCALE PATTERN IS
QUITE SIMILAR SUNDAY INTO MONDAY...BUT THE DETAILS FOR OUR AREA
ARE QUITE DIFFERENT. CURRENTLY FAVORED THE GFS FOR SATURDAY...
WHICH WOULD GIVE US A DRY DAY BUT THE ECMWF IS WET. THE OPPOSITE
IS TRUE FOR SUNDAY. FOR NOW LEANED MORE TOWARD THE GFS SOLUTION
BUT CONFIDENCE IS NORMAL TO BELOW NORMAL. MAIN AREA OF SHOWERS AND
THUNDERSTORMS SHOULD SHIFT TO THE NORTHERN PLAINS MONDAY AND
MONDAY NIGHT...BUT SOME PRECIPITATION IS POSSIBLE ALONG THE FRONT
THAT WILL BE OVER OUR AREA.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
SHOWERS AND THUNDERSTORMS HAD LIFTED NORTHEAST OF THE TAF SITES
BY 20Z. ADDITIONAL SHOWERS AND THUNDERSTORMS ARE EXPECTED TO
REDEVELOP THIS EVENING AND OVERNIGHT AT ALL THREE TAFS SITES.
MVFR/IFR CEILINGS AND VISIBILITIES ARE EXPECTED AT TIMES. SURFACE
WINDS WILL BE FROM THE SOUTHEAST THROUGH NORTHEAST 10 TO 15 KNOTS
WITH LOCALLY HIGHER GUSTS. WINDS WILL INCREASE WEDNESDAY...WITH
THE STRONGEST WINDS EXPECTED AT KOFK...POSSIBLY INCREASING TO
OVER 25 KNOTS.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...FLASH FLOOD WATCH FROM 6 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR NEZ015>018-030>034-042>045-050>053-065>068-078-
088>093.
IA...FLASH FLOOD WATCH FROM 6 PM CDT THIS EVENING THROUGH WEDNESDAY
MORNING FOR IAZ043-055-069-079-090.
&&
$$
SHORT TERM...ZAPOTOCNY/MILLER
LONG TERM....MILLER
AVIATION...ZAPOTOCNY/MILLER