000 
FXUS65 KVEF 211807 AAA
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1106 AM PDT SAT JUN 21 2008

.SYNOPSIS...WELL ABOVE NORMAL HIGH TEMPERATURES WILL PERSIST THROUGH 
THE WEEKEND WITH THE WARMEST READINGS EXPECTED TODAY. A SLIGHT 
DECREASE IN TEMPERATURES WILL OCCUR SUNDAY AND MONDAY AS A WEAK 
FRONT PASSES OVER THE AREA...RESULTING IN LOCALLY BREEZY CONDITIONS 
IN THE AFTERNOONS.
&&

.UPDATE...AMENDED FORECAST TO PUT IN THUNDERSTORMS THIS AFTERNOON 
AND EVENING IN THE SIERRA AND WHITE MOUNTAIN RANGES OF INYO COUNTY.
CUMULUS ALREADY FORMING AND OTHER PARAMETERS IN PLACE FOR HIGH BASED 
THUNDERSTORMS. WILL NEED TO LOOK AT SUNDAY AS WELL FOR THUNDER IN 
INYO AND ESMERALDA COUNTIES AS INSTABILITY...LOW LEVEL CONVERGENCE 
AND A LAYER OF H5 TO H6 MOISTURE COULD MAKE FOR HIGH BASED THUNDER 
THERE AS WELL. OTHERWISE REST OF FORECAST LOOKS GOOD AND ON TRACK.
&&

.PREV DISCUSSION...SHORT TERM...OVERALL RIDGE OF HIGH PRESSURE TO 
REMAIN THE DOMINANT FEATHER THROUGH THE SHORT TERM...HOWEVER WEAK 
SHORT WAVE MOVING THROUGH THE PACIFIC NORTHWEST AND NORTHERN NEVADA 
LATE TODAY AND SUNDAY WILL LOWER HEIGHTS AND THICKNESS INTO SUNDAY 
AND MONDAY. ALTHOUGH GENERALLY CLOUD FREE SKIES EXPECTED ACROSS THE 
CWA THROUGH THE SHORT TERM...AS SHORT WAVE CROSSES OVER THE AREA 
WEAK DYNAMICS ACROSS THE EXTREME NORTHERN PORTION OF THE CWA WITH 
SLIGHT CHANCE OF AFTERNOON TSTORMS TODAY OVER MAINLY ESMERALDA 
COUNTY WITH A FEW CU ELSEWHERE. SHORT WAVE EXITING THE AREA BY 
SUNDAY SHOULD STABILIZE NORTHERN PORTION ONCE AGAIN SUNDAY AND 
MONDAY. SHORT WAVE WILL ALSO BE RESPONSIBLE FOR SLIGHT INCREASE IN 
AFTERNOON WINDS TODAY AND SUNDAY WITH MAIN CONCERN BEING WESTERN SAN 
BERNARDINO COUNTY/MOHAVE COUNTY RESULTING IN FIRE WEATHER CONCERNS 
WITH BREEZY/LOW RELATIVE HUMIDITY COMBINATION. PLEASE SEE FIRE 
WEATHER DISCUSSION. WITH RIDGE BEING THE STRONGEST OVER THE AREA 
TODAY...EXPECT AFTERNOON TEMPS TO PEAK TODAY THEN DECREASE SLIGHTLY 
SUNDAY AND INTO THE FIRST OF NEXT WEEK. WILL HIGHLIGHT LAS VEGAS 
VALLEY AND COLORADO RIVER VALLEY WITH NEAR RECORDS FOR TODAY AND THE 
COLORADO RIVER VALLEY AGAIN FOR SUNDAY.

.LONG TERM...A DRY SOUTHWEST FLOW IS EXPECTED TO REMAIN OVER THE 
REGION THROUGH THE EXTENDED PERIOD. MODELS ARE SHOWING AN UPPER 
LEVEL LOW DEVELOPING OFF THE CENTRAL/SOUTHERN CA COAST THURSDAY 
WHICH WILL HELP TO PUSH THE UPPER HIGH CENTER WHICH IS LOCATED OVER 
NORTHERN MEXICO SLIGHTLY EAST. THIS IS EXPECTED TO KEEP CONDITIONS 
DRY...BUT MAY LOWER HEIGHTS A BIT. THIS WOULD BRING SLIGHTLY COOLER 
TEMPERATURES TO THE REGION...BUT ONLY FALLING TO NEAR NORMAL. SOME 
MOISTURE MAY GET WRAPPED NORTHWARD AROUND THE HIGH...BUT MODELS ARE 
SHOWING THIS TO REMAIN IN CENTRAL AND EASTERN ARIZONA WITH ONLY DRY 
CONDITIONS WEST. 
&&

.AVIATION...FOR MCCARRAN...NO SIGNIFICANT WEATHER EXPECTED WITH 
CLEAR SKIES AND LIGHT WINDS FOLLOWING A TYPICAL DIURNAL PATTERN. 
HIGH TEMPERATURES WILL CLIMB NEAR 110 DEGREES...HITTING 100 DEGREES 
AROUND 18Z SATURDAY MORNING.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST 
CALIFORNIA...LIGHT WINDS FOLLOWING TYPICAL DAY/NIGHT PATTERNS AND 
CLEAR SKIES WILL PREVAIL OVER THE NEXT 24 HOURS. NO SIGNIFICANT 
WEATHER IS EXPECTED.
&&

FIRE WEATHER...STRONG RIDGE OF HIGH PRESSURE TO REMAIN OVER THE 
DISTRICT THROUGH THE WEEKEND...HOWEVER WEAKENING SLIGHTLY INTO 
SUNDAY AND THE FIRST OF NEXT WEEK AS A WEAK STORM MOVES ACROSS THE 
PACIFIC NORTHWEST. THIS SYSTEM WILL ALLOW FOR LOCALLY BREEZY 
CONDITIONS TO FORM...MAINLY OVER THE WESTERN PORTION OF SAN 
BERNARDINO COUNTY AND MOHAVE COUNTY LATE TODAY AND INTO SUNDAY. 
HOWEVER OVERALL WIND SPEEDS ARE EXPECTED TO REMAIN BELOW CRITICAL 
THRESHOLDS AT THIS TIME. ALTHOUGH WINDS ARE EXPECTED TO REMAIN BELOW 
CRITICAL THRESHOLDS...MINIMUM RELATIVE HUMIDITY VALUES WILL REMAIN 
AROUND 5 PERCENT DURING THE AFTERNOONS WITH RECOVERIES ONLY REACHING 
15-20 PERCENT MOST AREAS THROUGH TUESDAY MORNING.
&&

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

$$

JACQUES/JENSEN/GORELOW

HTTP://WEATHER.GOV/LASVEGAS