330 
FXUS63 KLBF 181748
AFDLBF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NORTH PLATTE NE
1248 PM CDT TUE SEP 18 2012

.AVIATION...
VFR CONDITIONS THE NEXT 24 HOURS. CLEAR SKIES THE REST OF TODAY
WITH WEST TO NORTHWEST WINDS GUSTING AS HIGH AS 20 KTS...ALTHOUGH
MOST WINDS WILL GENERALLY BE AROUND 10 TO 15 KTS. 

WEAK COLD FRONTAL PASSAGE LATE TONIGHT INTO TOMORROW. COULD SEE A
SLIGHT INCREASE OF MID/HIGH CLOUDS ALONG AND AHEAD OF THE FRONT.
OTHER CHANGES WILL BE SLIGHTLY COOLER TEMPS AND NORTHWEST WINDS
GUSTING TO 20 TO 25 KTS BEHIND THE FRONT.

&&

.PREV DISCUSSION... /ISSUED 335 AM CDT TUE SEP 18 2012/

SHORT TERM...TODAY THROUGH THURSDAY.
AS A SURFACE TROUGH PUSHES EAST ACROSS THE AREA TODAY...EXPECT WARM 
AND DRY CONDITIONS. WINDS WILL SHIFT TO THE NORTHWEST BEHIND THE 
TROUGH...WITH WARMING DOWNSLOPE WINDS HELPING TO PUSH TEMPERATURES 
INTO THE MID 70S TO LOWER 80S. LOW RELATIVE HUMIDITY IS ALSO 
EXPECTED TO ACCOMPANY THE WARM TEMPERATURES...BUT IT APPEARS THAT IT 
SHOULD STAY ABOVE CRITICAL VALUES. FIRE DANGER WILL BE THERE...JUST 
NOT EXPECTING IT TO REACH CRITICAL STATUS. A COLD FRONT WILL PUSH 
SOUTHEAST ACROSS THE AREA THURSDAY. TEMPERATURES WILL WARM INTO THE 
80S ACROSS CENTRAL AND SOUTHWEST NEBRASKA BY MIDDAY...PRIOR TO THE 
FRONTAL PASSAGE. DEW POINTS WILL BE A FEW DEGREES LOWER THAN 
TODAY...AND EXPECTING NEAR CRITICAL FIRE WEATHER CONDITIONS TO 
DEVELOP. THE AREA OF MOST CONCERN WILL BE SOUTHEAST OF AN ONEILL TO 
NORTH PLATTE LINE. WARM AND DRY CONDITIONS WILL CONTINUE INTO 
THURSDAY...WITH AGAIN FIRE WEATHER A CONCERN. 

LONG TERM...FRIDAY THROUGH MONDAY.
ANOTHER COLD FRONT WILL DROP SOUTH INTO THE AREA FRIDAY. BOTH THE 
GFS AND ECMWF HAVE BACKED OFF A LITTLE ON THE AMOUNT OF COOLER AIR 
FILTERING INTO THE AREA BEHIND THE FRONT...AND WILL TWEAK HIGHS UP 
JUST A TAD. A REINFORCING SHOT OF COLDER AIR ARRIVES SATURDAY ON THE 
BACKSIDE OF A LARGE LONG WAVE TROUGH THAT DEVELOPS SOUTH THROUGH 
THE GREAT LAKES REGION. ECWMF IS THE MOST AGGRESSIVE WITH THE COLD 
AIR PUSHING INTO THE AREA...WITH H85 TEMPS RANGING FROM 2C TO 10C 
EAST TO WEST ACROSS THE FORECAST AREA. THE GFS ENSEMBLE MEAN IS 
ABOUT 7C TO 15C EAST TO WEST...AND THE OPERATIONAL GFS IS 7C TO 17C. 
DGEX IS SIMILAR TO THE GFS AND GFS ENSEMBLE. AT THIS TIME...WILL 
SHAVE A DEGREE OR TWO OFF HIGHS FROM PREVIOUS FORECAST...BUT WON/T 
GO NEAR AS COLD AS THE ECMWF. IF THE OTHER MODELS BEGIN TO TREND 
TOWARD THE ECMWF...THEN THE CURRENT FORECASTED HIGHS WILL HAVE TO BE 
LOWERED A FEW DEGREES. ALL MODELS AGREE A WARM UP BEGINS SUNDAY AND 
CONTINUES INTO THE FIRST OF NEXT WEEK...WITH HIGHS EXPECTED IN THE 
80S MOST AREAS MONDAY.         

FIRE WEATHER...
WEDNESDAY WILL SEE MINIMUM RELATIVE HUMIDITY FALL TO AROUND 20
PERCENT OVER WESTERN AND NORTH CENTRAL NEBRASKA AS A DRY COLD
FRONTAL BOUNDARY MOVES SOUTH ACROSS THE STATE. WINDS ARE
EXPECTED...WITH FREQUENT GUSTS ABOVE 25 MPH. MAIN AREA OF CONCERN
WILL BE FIRE WEATHER ZONE 209 WHERE 20 PERCENT MINIMUM RELATIVE
HUMIDITY IS THRESHOLD. WILL HOLD OFF ON WATCH FOR NOW BUT
EMPHASIZE IN HAZARDOUS WEATHER OUTLOOK.

&&

.LBF WATCHES/WARNINGS/ADVISORIES...NONE.

&&

$$


AVIATION...MASEK