FXUS65 KVEF 082308
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
300 PM PST TUE DEC 8 2009

SYNOPSIS...DRY NORTHWEST FLOW WILL BE OVER THE REGION THROUGH 
WEDNESDAY AS WEAK HIGH PRESSURE BUILDS INLAND. THE WEATHER PATTERN 
WILL REMAIN UNSETTLED THE REST OF THE WEEK AS A WEAK PACIFIC SYSTEM 
MOVES INLAND EARLY FRIDAY FOLLOWED BY A STRONGER ONE SATURDAY AND 
SUNDAY.
&&

.SHORT TERM...DRY NORTHWEST FLOW OVER THE AREA TODAY AS THE SYSTEM 
THAT BROUGHT ALL THE RAIN AND SNOW PUSHES FURTHER AWAY FROM THE 
AREA. THERE HAVE BEEN A FEW LINGERING CLOUDS OVER NORTHERN MOHAVE 
COUNTY AND A SNOW FLURRY OR TWO WILL BE POSSIBLE AT LEAST THROUGH 
SUNSET. WATER VAPOR IMAGERY SHOWING A WEAK IMPULSE PUSHING INTO 
NORTHWEST NEVADA THAT WILL QUICKLY BRUSH THE NORTHEASTERN PART OF 
THE STATE. THIS WILL HAVE MINIMAL IMPACT ON OUR FORECAST AND EVEN 
SURFACE PRESSURE GRADIENTS WILL REMAIN WEAK. THESE WEAK GRADIENTS 
COMBINED WITH CLEAR SKIES AND DRY CONDITIONS WILL LEAD TO VERY COLD 
TEMPERATURES OVERNIGHT. TEMPERATURES ARE EXPECTED TO BE COLDER THAN 
LAST WEEK WITH A FORECASTED OVERNIGHT LOW AT MCCARRAN OF 28 DEGREES 
WITH SOME OUTLYING LAS VEGAS VALLEY LOCATIONS IN THE LOWER 20S. SOME 
PLACES ACROSS THE NORTHERN CWA...THAT HAVE SNOW COVER...ARE LIKELY 
TO SEE TEMPERATURES DIPPING INTO THE SINGLE DIGITS. A FREEZE WARNING 
WILL NOT BE ISSUED BECAUSE THIS IS NOT THE FIRST FREEZE OF THE 
SEASON AND WIDESPREAD TEMPERATURES IN THE VALLEY ARE NOT EXPECTED TO 
REACH 20 DEGREES. MODELS ARE STILL INDICATING A WEAK SYSTEM 
APPROACHING THE WEST COAST THURSDAY AND FRIDAY WITH HIGH LEVEL 
MOISTURE BEGINNING TO SPREAD OVER THE CWA LATE WEDNESDAY AND 
THURSDAY. MODELS HAVE SLOWED THIS SYSTEM DOWN WITH PRECIPITATION NOW 
PUSHING INTO THE SIERRA LATE THURSDAY AND THEN GRADUALLY SPREADING 
EAST ON FRIDAY.
&&

.LONG TERM...A MINOR RIPPLE IN THE FLOW COULD BRING MAINLY MOUNTAIN 
SHOWERS TO THE REGION FRIDAY BUT THE BIGGER STORY IS THAT MODELS ARE 
FORECASTING A MORE POTENT SYSTEM FOR SATURDAY. IT LACKS THE STRONG 
WIND AND ARCTIC CHARACTERISTICS THAT THE MONDAY STORM HAD BUT IS 
FORECAST TO HAVE SUFFICIENT MOISTURE TO PRODUCE DECENT RAIN AND 
SNOWFALL AMOUNTS FOR MUCH OF THE SOUTHERN GREAT BASIN AND MOJAVE 
DESERT. IMPROVING WEATHER CONDITIONS EXPECTED SUNDAY AS THE STORM 
PULLS AWAY WITH HIGH PRESSURE AND WARMER TEMPERATURES RETURNING 
EARLY NEXT WEEK. 
&&

.AVIATION...FOR MCCARRAN...VARIABLE DAYTIME WINDS WITH LIGHT 
SOUTHWEST FLOW OVERNIGHT EXPECTED THROUGH THURSDAY. MOSTLY CLEAR 
SKIES THROUGH WEDNESDAY FOLLOWED BY INCREASING HIGH CLOUDS THURSDAY.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST 
CALIFORNIA...FEW-SCT CLOUDS AROUND 8K FEET ACROSS THE NORTH THIS 
EVENING OTHERWISE CLEAR. WINDS ARE EXPECTED TO BE GENERALLY LIGHT 
AND FOLLOW TYPICAL DIURNAL DIRECTIONS.

.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE.
CA...NONE.
&&

$$

GORELOW/SALMEN

HTTP://WEATHER.GOV/LASVEGAS