FXUS65 KVEF 290440
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
840 PM PST SAT NOV 28 2009

.SYNOPSIS...ISOLATED SHOWERS WILL CONTINUE ACROSS MUCH OF THE AREA 
TONIGHT BEFORE DRYING ON SUNDAY AS A WEAK RIDGE OF HIGH PRESSURE 
BUILDS OVER THE REGION INTO NEXT WEEK. TEMPERATURES ARE EXPECTED
TO BE NEAR NORMAL INTO THE MIDDLE OF NEXT WEEK.
&&

.UPDATE...UPPER LOW CIRCULATION CENTERED TO THE SOUTH OF KLAS 
CONTINUES TO ROTATE MOISTURE ACROSS SOUTHERN NEVADA/NORTHWEST 
ARIZONA AND SOUTHEAST CALIFORNIA. BANDS OF SHOWERS DIFFICULT TO TIME 
AS THEY FORM AND DISSIPATE...SO OVERALL BROADBRUSH FORECAST FOR THE 
ABOVE MENTIONED AREA LOOKS GOOD FOR TONIGHT. DUE TO THE EASTERLY 
FLOW AROUND THE LOW AND INTO THE SOUTHERN NEVADA MOUNTAINS...WILL 
CONTINUE THE WINTER WEATHER ADVISORY FOR SNOW ACCUMULATIONS UP TO 
6INCHES BY MORNING. HOWEVER...SURFACE PRESSURE GRADIENTS/FLOW ALOFT 
AND NOT COMBINED TO PRODUCE THE STRONG AND GUSTY WINDS OVER THE 
OWENS VALLEY WHICH WERE PREVIOUSLY EXPECTED AND HAVE CANCELLED THE 
WIND ADVISORY FOR THIS AREA. AS THE LOW CONTINUES TO MOVE 
SOUTH...IMPROVING CONDITIONS EXPECTED CWA WIDE ON SUNDAY. OVERALL 
SHORT TERM FORECAST ON TRACK. WILL UPDATE ZONES SHORTLY TO REMOVE 
WIND ADVISORY WITH GRIDS ALREADY SENT.
&&

.AVIATION...FOR MCCARRAN...UPPER LOW TO THE SOUTH OF KLAS WILL 
CONTINUE TO ROTATE BANDS OF SHOWERS ACROSS THE KLAS VALLEY INTO LATE 
TONIGHT BEFORE DRIER FLOW MOVES INTO THE AREA ON SUNDAY. WILL KEEP 
VCNTY SHOWERS IN THE TAF THROUGH 12Z WITH SCT-BKN CLOUDS GENERALLY 
AOA 8K FEET. WINDS WILL BE ERRATIC NEAR SHOWERS...BUT TREND OUT OF 
THE WEST THROUGH 08Z THEN BECOME MORE NORTH GENERALLY 8-12KTS 
THROUGH MUCH OF SUNDAY.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST 
CALIFORNIA...AN UPPER LOW WILL CONTINUE TO BRING SCATTERED SHOWERS 
TO SOUTHERN NEVADA AND THE SAN BERNARDINO/INYO COUNTY THROUGH LATE 
TONIGHT. OVER MOHAVE COUNTY EXPECT SHOWERS TO CONTINUE THROUGH 
SUNDAY AFTERNOON. CLOUD LAYERS WILL GENERALLY BE SCT-BKN 8K-12K FEET 
HOWEVER LOCALLY LOWER NEAR SHOWERS. MOUNTAIN TOP OBSCURATIONS LIKELY 
THROUGH SUNDAY MORNING. DRIER AIR WILL MOVE INTO THE AREA BY SUNDAY 
AFTERNOON WITH FEW-SCT CLOUDS AT 8K-10K FEET ACROSS SOUTHERN NEVADA 
AND SOUTHEAST CALIFORNIA BY 18Z SUNDAY. WINDS WILL BE ERRATIC NEAR 
SHOWERS TONIGHT AND THEN BECOME NORTH BY LATE TONIGHT AND SUNDAY 
ACROSS MUCH OF THE AREA. SPEEDS WILL GENERALLY BE BETWEEN 
8-12KTS...BUT LOCALLY GUSTY IN NORTH WIND PRONE AREAS.
&&

.PREV DISCUSSION...253 PM PST SAT SHORT TERM...SATELLITE AND RADAR 
IMAGERY SHOWS OBVIOUS CYCLONIC ROTATION OVER THE CWA WITH THE CENTER 
OF THE LOW OVER EASTERN SAN BERNARDINO COUNTY. ENHANCED SHOWER 
ACTIVITY IS EVIDENT EAST OF THE LOW CENTER OVER NORTHEASTERN SAN 
BERN...SOUTHERN CLARK AND WEST CENTRAL MOHAVE COUNTIES. SO FAR 
PRECIPITATION AMOUNT WISE...DAGGETT AP IS THE WINNER WITH .18 INCHES 
OF RAIN. AS OF THIS WRITING...NO SIERRA SNOW TOTALS WERE AVAILABLE. 
A BAND OF SHOWERS STRETCHING FROM KINGMAN TO BOULDER CITY IS THE 
FOCUS FOR POTENTIAL SHOWER ACTIVITY IN THE LAS VEGAS VALLEY AND 
SNOWFALL IN THE SPRING MTNS AND SHEEP RANGE FOR THE REST OF THE 
AFTERNOON INTO THE EVENING. THIS BAND IS WRAPPING AROUND THE 
NORTHEAST QUADRANT OF THE LOW AND MOVING TOWARDS THE VALLEY. SO 
FAR...NO LIGHTNING HAS BEEN ASSOCIATED WITH IT BUT CAN NOT BE RULED 
OUT WITH THE BEST INSTABILITY UNDER THE COLD POOL ALOFT JUST SOUTH 
OF THE VALLEY. IF RAIN DOES DEVELOP IN THE VALLEY...THE BEST SHOT 
WILL BE FROM NOW UNTIL AROUND DAYBREAK SUNDAY.

SUNDAY SHOULD BE RELATIVELY DRY AREA WIDE BY THE AFTERNOON HOURS 
WITH THE POSSIBLE EXCEPTION OF SOUTHERN MOHAVE COUNTY. GUSTY NORTH 
TO NORTHEAST WILL MAKE SEASONAL TEMPERATURES FEEL COOLER OVER MUCH 
OF THE AREA FOR AT LEAST PART OF THE DAY ON SUNDAY BUT CONDITIONS 
ARE EXPECTED TO SLOWLY IMPROVE AS SUNDAY ROLLS INTO MONDAY. THE 
SYSTEM IS FORECAST TO CONTINUE TO PULL AWAY FROM THE REGION MONDAY 
AND CONDITIONS IMPROVE WITH LIGHTER WINDS...SEASONAL TEMPS AND 
MOSTLY CLEAR SKIES.

.LONG TERM...OVERALL THE LONGER RANGE MODEL AGREEMENT REMAINED ON 
THE POOR SIDE THIS AFTERNOON ESPECIALLY TOWARDS NEXT WEEKEND SO ONCE 
AGAIN I MADE FEW CHANGES TO THE FORECAST. AN UPPER RIDGE CONTINUES 
TO BE PROGGED OVER THE AREA FOR TUESDAY AFTERNOON WHICH SHOULD 
SUPPORT DRY WEATHER. DUE TO INVERSIONS OVER THE VALLEYS AND WEAK 
MIXING HIGH TEMPS WILL GENERALLY ONLY BE AROUND NORMAL WITH THE BEST 
WARMING IN THE HIGHER ELEVATIONS ABOVE THE INVERSION HEIGHT. MODELS 
CONTINUE TO DIVERGE WITH THERE IDEAS ON A SYSTEM PROGGED ON 
WEDNESDAY. THE 12Z ECMWF DROVE AN UPPER LOW SOUTH ACROSS NEVADA 
WHILE THE GEM AND GFS MODELS MOVED A WEAK RIPPLE SOUTHWARD ACROSS 
CALIFORNIA. FOR NOW NONE OF THE SOLUTIONS WOULD BRING US ANY SHOWERS 
BUT AN INCREASE IN HIGH CLOUDS AND ENHANCED NORTHERLY WINDS LOOK TO 
BE THE MAIN IMPACT FROM WEDNESDAY AFTERNOON INTO WEDNESDAY NIGHT.

BY THURSDAY TEMPS LOWER BACK TO AROUND NORMAL UNDER DRY NORTHWEST 
FLOW. AFTER THAT...ALL BETS ARE OFF AS TO WHAT GOES ON NEXT WEEKEND 
WITH THE 12Z GFS AND 00Z GEM MODELS DROPPING A LARGE CLOSED LOW 
TOWARDS THE SOUTHWESTERN U.S. WHILE THE 12Z ECMWF KEEPS THE AREA IN 
A DRY WEST TO NORTHWEST FLOW WITH ANY SORT OF SYSTEM HOLDING OFF 
UNTIL NEXT MONDAY. FOR NOW...MAINTAINED A DRY FORECAST WITH TEMPS 
RIGHT AROUND NORMAL.  
&&

.CLIMATE...BELOW IS A LIST OF THE LAST TIME MEASURABLE PRECIPITATION 
(AT LEAST 0.01 OF AN INCH) HAS FALLEN AT A FEW LOCATIONS AROUND THE 
AREA PRIOR TO TODAY. ALL DATES ARE FOR THIS YEAR.

LAS VEGAS/MCCARRAN...AUGUST 22ND 
BISHOP...............OCTOBER 14TH 
BARSTOW-DAGGETT......JULY 19TH 
NEEDLES..............AUGUST 23RD
DEATH VALLEY.........AUGUST 24TH
KINGMAN..............SEPTEMBER 18TH
&&

.VEF WATCHES/WARNINGS/ADVISORIES...
NV...WINTER WEATHER ADVISORY UNTIL 4 AM PST SUNDAY FOR NVZ018-019.
AZ...NONE.
CA...NONE.
&&

$$

JENSEN/SALMEN/STACHELSKI

HTTP://WEATHER.GOV/LASVEGAS