FXUS63 KOAX 181508
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
1008 AM CDT MON APR 18 2011
.UPDATE...
UPDATED TO INCLUDE MORNING SHOWERS IN SOUTHEAST NEBRASKA/LOWER MAX
TEMPS TODAY
&&
.DISCUSSION...
ZONES/GRIDS WERE UPDATED TO BOTH MENTION SCATTERED SHOWERS SE AND
TO LOWER TEMPERATURES TODAY. A SMALL AREA OF SHOWERS THAT WERE NORTH
OF THE H85 FRONT WORKING TOWARD LNK PROMPTED THE INCLUSION OF
SHOWERS SE THRU 18Z. OTHERWISE LOW CLOUDS WILL PROBABLY NOT ERODE
MUCH TODAY AS SFC FLOW REMAINS MORE ENE...ALTHOUGH SOME EROSION
COULD OCCUR FAR NERN ZONES AND FAR SOUTH. NONETHELESS...CUT A FEW
DEGREES OFF OF MOST HIGHS TODAY. CHERMOK
&&
.PREV DISCUSSION... /ISSUED 322 AM CDT MON APR 18 2011/
DISCUSSION...
UPPER WAVE THAT BROUGHT SHOWERS TO MUCH OF THE AREA YESTERDAY HAS
PUSHED WELL TO THE EAST OF THE REGION. OVERALL SUBSIDENCE IN ITS
WAKE SHOULD LEAVE MUCH OF THE FORECAST AREA DRY THIS MORNING...ALTHOUGH
STRATUS HAD DEVELOPED ACROSS ALONG/NORTH OF INTERSTATE 80. WHILE
SOME PATCHY FOG MAY BE POSSIBLE IN NORTHEAST NEBRASKA...IT
SHOULDN'T BE AS WIDESPREAD AS IT WAS YESTERDAY MORNING.
THE NEXT WAVE MOVING INTO THE PACIFIC NORTHWEST WILL BEGIN TO
SPREAD SHOWERS BACK INTO THE AREA THIS AFTERNOON...PRIMARILY
ACROSS NORTHEAST NEBRASKA...WITH SOME SPRINKLES POSSIBLE TOWARD
EARLY EVENING AS FAR SOUTH AS I80. OVERALL IT WILL BE A CLOUDY AND
COOL DAY WITH A SURFACE FRONT REMAINING WELL TO THE SOUTH OF THE
REGION...WITH BELOW NORMAL TEMPS.
THIS SETS THE STAGE FOR A VERY WET NIGHT TONIGHT AS LEE CYCLOGENESIS
TAKES PLACE...WITH A SURFACE LOW MOVING EASTWARD ALONG THE KS/OK
BORDER REGION. STRONG ISENTROPIC LIFT ACROSS OUR REGION WILL
RESULT IN SHOWERS BECOMING WIDESPREAD OVERNIGHT WITH AN AREA OF
MODERATE TO HEAVY RAIN EXPECTED...PERHAPS ORIENTED ALONG I80
THROUGH DAYBREAK. ALTHOUGH...THE NAM IS STILL TRENDING JUST A BIT
FURTHER NORTH AND KEEPS PRECIP OUT OF EXTREME SOUTHEAST NEBRASKA
AND SOUTHWEST IOWA UNTIL LATER ON TUESDAY...BUT THIS MODEL SEEMS
TO BE AN OUTLIER. NOT OVERLY EXCITED ABOUT THUNDERSTORMS AS THE
BETTER ELEVATED INSTABILITY REMAINS TO THE SOUTH ACROSS KANSAS AND
MISSOURI...BUT ISOLATED THUNDERSTORMS WILL STILL BE MENTIONED
ACROSS SOUTHEAST NEBRASKA AND SOUTHWEST IOWA.
TUESDAY WILL NOT BE A NICE DAY TO BE OUTDOORS. COLD RAIN WILL
CONTINUE TO MOVE THROUGH THE REGION...MODERATE AT TIMES...WITH A
COLD EASTERLY WIND BECOMING NORTH THROUGH THE DAY...AS THE SURFACE
LOW MOVES EASTWARD TO CENTRAL MISSOURI. HIGHS WILL REMAIN IN THE
40S...BUT 15 TO 25 MPH WINDS WILL MAKE IT FEEL LIKE THE LOWER TO
MID 30S. RAIN WILL REALLY BEGIN TO TAPER DOWN BY EARLY TUESDAY
EVENING WITH SOME LINGERING SHOWERS IN THE AREA...BUT AT THE SAME
TIME...COLDER AIR SPILLING INTO THE REGION ON THE BACKSIDE COULD
RESULT IN A RAIN/SNOW MIXTURE ACROSS NORTHEAST NEBRASKA AND
NORTHWEST IOWA...ALTHOUGH AM BANKING THAT MEASURABLE PRECIP
CHANCES WILL REALLY BE DWINDLING BY THE TIME THAT HAPPENS BY MID
TO LATE EVENING. COULD STILL BE SOME LINGERING SNOW SHOWERS
BETWEEN OMAHA AND SIOUX CITY EARLY WEDNESDAY MORNING...ALTHOUGH
LATEST SREF AND ECMWF MODELS SUGGEST IT COULD BE JUST A BIT
FURTHER NORTH. STILL NO ACCUMULATION EXPECTED WEDNESDAY MORNING
THOUGH. OVERALL... WIDESPREAD RAINFALL AMOUNTS FROM ONE HALF TO
ONE AND ONE HALF INCHES APPEAR PROBABLE MONDAY NIGHT THROUGH
TUESDAY NIGHT...WITH THE AXIS NEAR OR JUST NORTH OF THE
INTERSTATE.
THERE IS A BRIEF BREAK WEDNESDAY AFTERNOON AND EVENING...IN
ADVANCE OF THE NEXT WAVE THAT IS EXPECTED TO MOVE ACROSS THE
PLAINS LATE WEDNESDAY NIGHT THROUGH THURSDAY. THIS WILL POSSIBLY
BRING MORE RAIN TO THE REGION WITH CONTINUED COOLISH TEMPS...AND YET
ANOTHER POTENT WAVE MOVES IN FOR THURSDAY NIGHT AND FRIDAY BRINGING
EVEN MORE RAIN AND ADDITIONAL REINFORCING SHOT OF COOLER TEMPS.
DIDN'T MAKE ANY FORECAST CHANGES FOR THE WEEKEND...BUT THE ECMWF
SUGGESTS STILL ANOTHER WAVE MOVE INTO THE AREA ON SUNDAY...BUT THE
GFS HAS MORE OF THE ENERGY A BIT FURTHER SOUTH. CONSIDERING THAT
ITS STILL 6 DAYS OUT...WILL DEFER TO HPC AND THE NEXT SHIFT FOR
POSSIBLE CHANGES...ESPECIALLY CONSIDERING THE HOLIDAY WEEKEND.
DEWALD
AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
UNSETTLED WEATHER CONTINUES THROUGH THE FORECAST PERIOD WITH THE
SURFACE FRONT REMAINING TO OUR SOUTH AND A SHORTWAVE TROUGH
AFFECTING THE TAF SITES. THE COOL NORTHEAST AND EASTERLY FLOW AT
6-12KTS WILL KEEP THE LOW CLOUDS AROUND WITH MVFR/IFR/LIFR
CONDITIONS ALONG WITH SOME FOG. PRECIPITATION WILL BE ON THE
INCREASE THIS AFTERNOON AND AT KOFK...SPREADING SOUTHWARD TONIGHT.
WILL MENTION SHOWERS AT KOFK THIS AFTERNOON AND ADD THEM TO KOMA AND
KLNK AFTER 00Z.
ZAPOTOCNY
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
DEWALD/ZAPOTOCNY