FXUS63 KOAX 042103
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
403 PM CDT MON APR 4 2011
.SHORT TERM...TONIGHT
WINDS WILL QUICKLY DECREASE THIS EVENING AS SURFACE RIDGE TO THE
WEST SHIFTS EASTWARD THROUGH THE MISSOURI RIVER VALLEY. SC LATER
THIS AFTERNOON WILL DIMINISH THIS EVENING LEADING TO GENERALLY CLEAR
SKIES FOR THE FIRST HALF OF THE NIGHT...WITH SOME INCREASE IN CLOUDS
LATE. A COOL NIGHT IS IN STORE FOR THE CWA WITH TEMPERATURES QUICKLY
FALLING OFF THIS EVENING AS WINDS DIMINISH. TEMPERATURES WILL TEND
TO LEVEL OFF LATE AS CLOUDS AND WINDS INCREASE.
.LONG TERM...TUESDAY THROUGH MONDAY.
UNSETTLED WEATHER WILL CONTINUE THROUGH THE FORECAST PERIOD WITH
TEMPERATURES CLOSER TO NORMAL.
INITIAL CONCERNS FOR TUESDAY WERE TO ISSUE A RED FLAG WATCH AND
POTENTIAL FOR RED FLAG WARNING CONDITIONS. ALTHOUGH FUELS ARE NOT
AS HIGH AS THEY COULD BE...LOW RELATIVE HUMIDITY (20% OR LESS) AND
WINDS 25 MPH OR MORE ARE EXPECTED FOR PARTS OF THE FORECAST AREA
TUESDAY. STEEP LOW LEVEL LAPSE RATES SHOULD ALLOW FOR DECENT
MIXING. FOR NOW WILL HIGHLIGHT EXTREME FIRE DANGER IN THE
HAZARDOUS WEATHER OUTLOOK FOR AREAS ALONG AND SOUTH OF THE PLATTE
RIVER FROM BOONE TO SARPY SOUTHWARD AND FREMONT AND PAGE COUNTIES
IN SOUTHWEST IOWA. WILL EXPRESS CONCERN FOR RED FLAG CONDITIONS
FOR TUESDAY TO SUBSEQUENT SHIFTS WITH FAVORABLE LOW RH ALTHOUGH
WINDS AND FUELS MAY BE MORE MARGINAL. A FLAG WARNING MAY BE NEEDED
ESPECIALLY FOR SOUTHERN NEBRASKA COUNTIES WHERE THE LOWEST
RELATIVE HUMIDITIES LOWER TO 15 TO 20 PERCENT AND BEST SOUTHWEST
SURFACE WINDS ARE EXPECTED.
THE MID TROPOSPHERIC TROUGH OVER THE OHIO RIVER VALLEY TUESDAY
MORNING WILL CONTINUE TO SHIFT TO THE EAST AS A MID LEVEL RIDGE
BUILDS IN ACROSS THE MIDLANDS. MID LEVEL WARM AIR ADVECTION SHOULD
RESULT IN INCREASING MID LEVEL CLOUDS FOR TUESDAY. SOUTHWEST WINDS
AND FAVORABLE MIXING WILL ALLOW TEMPERATUES TO WARM INTO THE 60S
AND 70S. MEANWHILE SURFACE LOW PRESSURE WILL ORGANIZE OVER WESTERN
NEBRASKA. SHORT WAVE TROUGH ENERGY WILL FLATTEN THE RIDGE TUESDAY
NIGHT AND THIS WILL BRING THE SFC FRONT INTO NORTHEAST NEBRASKA
OVERNIGHT. AT THIS TIME THE BULK OF THE PRECIPITATION SHOULD HOLD
TO THE NORTH OF THE FORECAST AREA...HOWEVER TO HAVE SOME LOW POPS
MENTIONED IN THE NORTH. THE SURFACE FRONT CONTINUES TO PUSH SOUTH
BY WEDNESDAY MORNING AND DURING THE DAY WEDNESDAY. THE COOL PUSH
IS FAIRLY BENIGN AND WITH A MIX OF CLOUDS AND SUN...TEMPERATURES
SHOULD TOP OUT IN THE 60S WITH A FEW 50S NORTH.
THE PATTERN BECOMES UNSETTLED AS THE NEXT PIECE OF SHORTWAVE
TROUGH ENERGY MOVES INTO THE PLAINS WEDNESDAY NIGHT. ALTHOUGH THE
SURFACE BOUNDARY IS TO THE SOUTH...THERE IS MID LEVEL UPWARD
VERTICAL MOTION WITH THE SHORTWAVE TROF AND FAVORABLE UPPER LEVEL
JET SUPPORT. H85 THETA-E ADVECTION BEGINS TO INCREASE WEDNESDAY
NIGHT AND COULD SEE SOME SHOWERS BEGIN TO DEVELOP...HOWEVER AM
LOOKING FOR A MUCH BETTER CHANCE FOR RAIN/SHOWERS/THUNDERSTORMS
DURING THE DAY THURSDAY AND THEN MOVING OUT THURSDAY NIGHT.
WE ARE LOOKING FOR A BREAK IN THE WX FRIDAY...WITH AN INCREASING
CHANCE FOR PRECIPITATION SATURDAY INTO SUNDAY AS THE MAIN CLOSED
H5 LOW OVER THE SOUTHWEST U.S. MOVES INTO THE PLAINS. BY NOON
SUNDAY THERE ARE SOME FAIRLY SIGNIFICANT TIMING DIFFERENCES AS THE
GFS HAS A CLOSED LOW OVER SOUTH CENTRAL NEBRASKA AND THE 12Z ECMWF
HAS IT MUCH SLOWER OVER CENTRAL COLORADO. THE TRACK AND TIMING OF
THE STORM SYSTEM WILL SIGNIFICANTLY AFFECT TEMPERATURES. THERE IS
SOME COLD AIR ALOFT AND DEPENDING ON WHERE THE SURFACE LOW
TRACKS...WE COULD SEE SOME SEVERE STORMS MAKE IT INTO EASTERN
NEBRASKA AND WESTERN IOWA SUNDAY WITH THE COMBINATION OF A DRYLINE
AND DEWPOINTS IN THE 50S AND POTENTIAL FOR SOME 60S DEWPOINTS
AHEAD OF IT.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
VFR CONDITIONS ARE EXPECTED OVER THE NEXT 24 HOURS AT THE TAF SITES.
WINDS WILL DIMINISH THIS EVENING AND THEN BACK TO WEST
OVERNIGHT...BEFORE GOING SOUTHWEST TOWARD MORNING. SKC CONDITIONS
EXPECTED BY EVENING WITH SOME INCREASE IN MID LEVEL CLOUDS TOWARD
12Z AND INTO TUE MORNING.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
BOUSTEAD/ZAPOTOCNY/BOUSTEAD