Expires:No;;242413
FXUS63 KLBF 252042
AFDLBF
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
240 PM CST WED NOV 25 2009
.SYNOPSIS...
    IN THE UPPER LEVELS...6.7 MICRON IMAGERY SHOWED A DEVELOPING 
WAVE OFF THE WASHINGTON-BRITISH COLUMBIA COAST AND A CLOSED 
CIRCULATION OVER THE CENTRAL CALIFORNIA COAST. OTHERWISE...THE RIDGE 
OVER THE WESTERN INTER-MOUNTAIN REGION WAS MAKING ITS WAY EASTWARD. 
HAND ANALYSIS OF THE 20Z SURFACE DATA SHOWS HIGH PRESSURE OVER THE 
WESTERN INTER-MOUNTAIN REGION. A WARM FRONT STRETCHED FROM AN 
INTENSE CLOSED LOW IN THE GULF OF ALASKA ACROSS NORTHERN BRITISH 
COLUMBIA AND THROUGH CENTRAL ALBERTA INTO EASTERN MONTANA. 
ANOTHER...EVEN STRONGER...SURFACE LOW COULD BE SEEN IN THE BERING 
SEA. 
&&
.SHORT/MEDIUM RANGE...TONIGHT THROUGH SATURDAY NIGHT.
    AS THE UPPER LOW MOVES OUT OF THE PLAINS AND ACROSS THE 
MISSISSIPPI VALLEY TONIGHT AND THURSDAY...AN UPPER RIDGE WILL COME 
IN FROM THE WEST AND BRING WARMER TEMPERATURES TO CENTRAL AND 
WESTERN NEBRASKA. IN FACT...UNSEASONABLY WARM TEMPERATURES ARE 
LIKELY THURSDAY AND AGAIN FRIDAY.
    A FRONT IS EXPECTED TO COME THROUGH WESTERN NEBRASKA FRIDAY 
NIGHT AND SATURDAY AND COLDER TEMPERATURES ARE AGAIN EXPECTED. THE 
HIGHS SATURDAY WILL STILL BE ABOVE NORMAL...BUT THEY MAY BE REACHED 
FAIRLY EARLY IN THE DAY AND WILL NOT BE NEARLY AS WARM AS FRIDAY OR 
EVEN THURSDAY. COLD ADVECTION MAY BE STRONG ENOUGH FOR A NON-DIURNAL 
TEMPERATURE TREND SATURDAY...BUT THERE IS SOME UNCERTAINTY REGARDING 
THE STRENGTH AND TIMING OF THE COLD ADVECTION. ALSO...THE FRONT IS 
FAST MOVING AND FAIRLY STRONG...SO A MENTION OF SNOW SHOWERS IS 
APPROPRIATE SATURDAY NIGHT.   
     
.LONG RANGE...SUNDAY THROUGH WEDNESDAY.
    BIG NEWS WILL COME TOWARD THE END OF THE PERIOD...WHEN ALL 
MODELS ARE INDICATING A SIGNIFICANT INTRUSION OF ARCTIC AIR INTO THE 
CENTRAL AND NORTHERN PLAINS. BEFORE HAND...SUNDAY THOUGH 
TUESDAY...WEATHER SHOULD BE RATHER BENIGN. A COLD FRONT DOES PLOW 
THROUGH THE AREA ON SATURDAY...WITH BREEZY AND CHILLY CONDITIONS 
BEHIND THE FRONT ON SUNDAY. THE LATEST RUNS OF BOTH THE GFS AND 
ECMWF INDICATE RIDGING MONDAY AND TUESDAY AHEAD OF THE ARCTIC BLAST 
ANTICIPATED FOR WEDNESDAY. SHOULD SEE HIGHS IN THE 40S TO AROUND 50 
BOTH MONDAY AND TUESDAY...WITH 30S FOR WEDNESDAY BEHIND THE FRONT. 
CURRENT INDICATIONS ARE THAT ENOUGH FORCING WILL BE PRESENT WITH THE 
FRONTAL BOUNDARY WEDNESDAY TO INCLUDE A SLIGHT CHANCE OF SNOW 
SHOWERS. BEYOND WEDNESDAY THE REST OF THE WEEK IS LOOKING DOWNRIGHT 
COLD...ESPECIALLY IF ECMWF IS CORRECT IN DROPPING THE ENTIRE ARCTIC 
AIRMASS INTO THE CONUS.
&&
.AVIATION...
    WINDS SHOULD DIMINISH RAPIDLY LATE THIS AFTERNOON ACROSS WESTERN 
AND CENTRAL NEBRASKA...WITH LIGHT WEST WINDS UNDER 10 KTS FOR THE 
OVERNIGHT HOURS AND INTO THURSDAY MORNING. SKIES SHOULD BE CLEAR 
AFTER ANY STRATOCUMULUS DIMINISHES LATE THIS AFTERNOON.
&&
.LBF 
WATCHES/WARNINGS/ADVISORIES...NONE. 
&&
$$
SHORT/MEDIUM RANGE...SPRINGER
AVIATION/EXTENDED...TAYLOR