FXUS63 KOAX 232017
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
317 PM CDT SAT APR 23 2011
.SHORT TERM...TONIGHT AND TOMORROW
WEAK H7-H6 FRONTOGENESIS AIDING IN SPRINKLES/ISOLATED LIGHT SHOWERS
MOVING TOWARD SERN NEBRASKA AS OF 19Z...BUT ACTIVITY IS EXPECTED TO
END FAIRLY QUICKLY THIS EVENING WITH MID CLOUD CLEARING AS LIFT
ABATES AS WINDS IN THAT LEVEL VEER A LITTLE. LOWER CLOUDS ACROSS
NRN 1/2-2/3RDS OF THE FORECAST AREA SHOULD ALSO DECREASE THRU
EVENING. HOWEVER...PROBABLY ENOUGH CLOUDS OR MOISTURE IN GENERAL TO
KEEP LOWS A LITTLE ABOVE MAV/MET NUMBERS WHICH WOULD APPEAR TO NEED
MOSTLY CLEAR SKIES MUCH OF THE NIGHT TO BE REACHED. AS UPPER TROUGH
MOVES ACROSS SRN ROCKIES ON SUNDAY...MID LEVEL FRONTOGENESIS AGAIN
INCREASES ACROSS MOSTLY WRN/SRN FORECAST AREA...ESPECIALLY TOWARD
AND AFTER 18Z. THIS SHOULD INCREASE CLOUDS WEST AND SOUTH AT LEAST
AND ALLOW NRN/NERN ZONES TO BE A BIT WARMER. A LITTLE DISCREPANCY
IN 18Z-00Z PD BETWEEN NAM...BETTER LIFT AND MOST QPF W OF FORECAST
AREA AND GFS...WHICH HAD A STRONGER BELT OF SWRLY WINDS AT H7
FARTHER NE THAN NAM AND THUS WAS MORE BULLISH WITH QPF THIS FAR NE.
IN ANY EVEN AMOUNTS WERE STILL FAIRLY LIGHT. ALTHOUGH DID TRIM BACK
MORNING POPS ON FAR NW EDGE...LEFT IN FAIRLY WIDESPREAD POPS SUNDAY
AFTERNOON ALTHOUGH CHC POPS WERE RESTRICTED TO SW 1/2 OR SO.
CHERMOK
.LONG TERM...TOMORROW NIGHT THROUGH SATURDAY
MAIN FORECAST CONCERNS ARE RAIN CHANCES SUNDAY NIGHT THROUGH MONDAY
NIGHT...AS WELL AS NEXT SIGNIFICANT SYSTEM FRIDAY/SATURDAY. KEPT
POPS VERY LOW OR NIL ON SUNDAY NIGHT ACROSS THE AREA AS UPPER-LEVEL
WAVE APPROACHES. BAROCLINIC ZONE...WITH ATTENDANT HEAVIER RAIN AND
THUNDER...SHOULD REMAIN WELL SOUTH OF THE CWA. MEANWHILE...AS WAVE
EJECTS INTO THE PLAINS...PRECIP SHOULD DEVELOP IN WESTERN KS/NEB AND
MOVE EASTWARD ON MONDAY. THINK SUNDAY NIGHT SHOULD BE MAINLY DRY IN
THE CWA...AND KEPT MAINLY DRY EVERYWHERE...THOUGH DID BUMP UP TEMPS
AS CLOUDS INCREASE. LOWERED TEMPS ON MONDAY AS RAIN OVERSPREADS THE
AREA AND POCKET OF COOL MID-TEMPS SLIDES THROUGH IN WAKE OF THE
SURFACE/MID-LEVEL LOW. ALSO HELD ONTO PRECIP LONGER INTO MONDAY
NIGHT AS DEFORMATION ZONE SETS UP FROM EASTERN SD INTO NORTHEAST
NEB. DID CONTINUE TO DOWNPLAY PRECIP POTENTIAL FOR TUESDAY THROUGH
WEDNESDAY THOUGH...AS MODELS INDICATE VAGUE DIRTY FLOW ACROSS THE
AREA. MAIN AREAS OF PRECIP SHOULD BE BOTH NORTH AND SOUTHWEST OF
THE AREA...CENTERED AROUND THE FIRST UPPER LOW AS IT PULLS INTO THE
GREAT LAKES AND A DEVELOPING SECOND TROUGH DIGGING ACROSS THE
SOUTHERN PLAINS. BELIEVE CWA WILL BE BETWEEN THE TWO AREAS OF
FORCING AND LARGELY DRY DURING THE PERIOD...THOUGH LIKELY CLOUDY AND
COOL.
TEMPERATURES WILL BEGIN TO MODERATE BY THURSDAY AS RATHER DEEP
UPPER-LEVEL LOW MOVES AWAY TO THE EAST AND WARM AIR
ADVECTION/WESTERLY FLOW PUSHES INTO THE PLAINS. WARM AIR ADVECTION
BECOMES PARTICULARLY STRONG ON FRIDAY AHEAD OF THE NEXT UPPER LOW
MOVING THROUGH THE NORTHERN PLAINS...WITH MID-LEVEL MOISTURE
ADVECTION AS MID-LEVEL FLOW RETURNS OFF THE GULF. ANOTHER DEEP LOW
IS PROGGED TO SLIDE FROM WESTERN CANADA TOWARD THE DAKOTAS/MN ON
FRIDAY/SATURDAY...DRAWING WARM/MOIST AIR NORTHWARD INTO THE AREA.
HAVE ADDED POPS TO FRIDAY AND INCREASED ON FRIDAY NIGHT...NOTING
THAT ECMWF IS FASTER THAN GFS SOLUTION IN EJECTING THE LOW AND IS
FARTHER SOUTH. INCLUDED THUNDER MENTION ON FRIDAY AND FRIDAY NIGHT
AS CWA IS PROGGED TO BE IN THE WARM SECTOR OF THE SYSTEM. DID KEEP
A LINGERING SLIGHT CHANCE POP INTO SATURDAY...THOUGH IN WAKE OF THE
DEEP LOW...IT IS LIKELY THAT THE AREA WILL BE DRY SLOTTED. ALSO
SHOULD COOL DOWN BEHIND THE LOW.
MAYES
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
18Z TAFS
LOW CLOUDS SHOULD DISSIPATE OR MOVE EAST OF TAF SITES BY 24/01Z OR
SO. MOST CEILINGS THROUGH THAT TIME SHOULD BE ABOVE 3K
FEET...ALTHOUGH THEY COULD BE A LITTLE BELOW 3K FT AT KOFK. MID
LEVEL CLOUDS AND SCATTERED LIGHT SHOWERS/SPRINKLES WILL MOVE INTO
SERN NEBRASKA THROUGH EARLY EVENING BUT SHOULD NOT HAVE AN IMPACT ON
TAF SITES. OTHERWISE A GENERAL CLEARING TREND EXPECTED TONIGHT AS
WINDS BECOME LIGHT AND VARIABLE AROUND SUNSET. MID LEVEL CLOUDS
WILL INCREASE ACROSS ERN NEBRASKA ON SUNDAY WITH SHOWER CHANCES AND
LOWERING CEILINGS SPREADING TOWARD TAF SITES AFTER 24/18Z.
CHERMOK
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$