FXUS63 KOAX 200846
AFDOAX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE OMAHA/VALLEY NE
345 AM CDT WED OCT 20 2010
.DISCUSSION...
THE MAIN FCST CONCERN IS PRECIPITATION AND POSSIBLE THUNDERSTORMS
FRIDAY THROUGH SATURDAY. BOTH GFS AND ECMWF MOVE CLOSED UPR LOW ATTM
OFF THE CA COAST I3NTO THE CNTRL PLAINS FRIDAY AND SATURDAY. ECMWF
HAS BEEN CONSISTENT IN PLACING THE UPR LO OVR CNTRL AND WRN NEBRASKA
BY 12Z SAT. GFS IS FURTHER SOUTHEAST WITH PLACEMENT. GFS HAS SLOWED
DOWN MORE IN LINE WITH ECMWF IN MOVG THIS SYS INTO THE PLAINS. ATTM
WILL TREND TO MORE OF A ECMWF SOLUTION WITH THIS SYSTEM. SFC LOW IS
FCST BY BOTH MODELS TO BE OVR WRN KS BY 06Z SAT AND THEN MOV INTOIA
BY 06Z SUN.
RAIN SHUD BEGIN ACRS THE SOUTHERN NEBRASKA ON FRIDAY MORNING AND
THEN SPREAD NWD DURG THE DAY. BY FRIDAY NIGHT AND SATURDAY...THERE
WILL BE ENOUGH INSTABILITY TO PRODUCE ISOLATED THUNDERSTORMS. THE
AMOUNT OF THUNDERSTORM ACTIVITY WILL ALSO BE DEPENDENT ON POSITION
OF THE SURFACE LOW AND WARM FRONT AS WELL AS AMOUNT OF SFC HEATING.
ATTM...I HAVE HAD THE GREATER CHANCES OF THUNDERSTORMS OVER
SOUTHEAST NEBRASKA ON SATURDAY.
RAIN IS EXPECTED TO DIMINISH ACROSS THE AREA ON SUNDAY NIGHT.
HOWEVER...A NORTHERN STREAM SHORTWAVE TROF AND ACCOMPANYING COLD
FRONT IS FCST TO MOVE ACROSS THE AREA MONDAY AFTERNOON AND EVENING
INTO TUESDAY MORNING. THERE WILL BE A CHANCE OF RAIN ALONG AND
BEHIND THE COLD FRONT MONDAY NIGHT INTO TUESDAY MORNING.
HIGHS ARE FCST IN THE 70S TODAY THROUGH FRIDAY...WITH COOLER TEMPS
IN THE 60S ON THE WEEKEND.
&&
.AVIATION...
TAF SITES KOFK/KOMA/KLNK
06Z TAFS
VFR CONDITIONS WILL PREVAIL THROUGH FORECAST PD. SFC HIGH PRESSURE
FROM NRN ROCKIES INTO SRN PLAINS WILL BRING W/NW SFC WINDS TO TAF
SITES THRU 21/00Z BFR WEAKENING/BECOMING MORE NRLY AS WEAK FRONT
SAGS SOUTH ACROSS ERN NEBR. SFC WINDS COULD GUST INTO 15-20KT RANGE
FOR A WHILE THIS AFTN AS HEATING MIXES DOWN SLIGHTLY STRONGER WINDS
ALOFT.
&&
.OAX WATCHES/WARNINGS/ADVISORIES...
NE...NONE.
IA...NONE.
&&
$$
SMITH/CHERMOK