394 
FXUS65 KVEF 221610
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
910 AM PDT THU OCT 22 2015

.SYNOPSIS...A LOW PRESSURE SYSTEM SLOWLY MOVING EAST ACROSS ARIZONA 
WILL RESULT IN DECREASING COVERAGE OF SHOWERS AND THUNDERSTORMS OVER 
NORTHWEST ARIZONA. A WEST TO NORTHWEST FLOW WILL DEVELOP BEHIND THE 
EXITING SYSTEM PROVIDING DRY WEATHER WITH NEAR NORMAL TEMPERATURES 
FRIDAY THROUGH THE WEEKEND. 
&&

.UPDATE...

WEAK SHORTWAVE TROUGH IS SLIDING ACROSS NORTHERN CALIFORNIA THIS 
MORNING. AS IT SLIDES THROUGH MAINLY NORTHERN AND CENTRAL NEVADA 
TODAY, IT COULD GENERATE A FEW SHOWERS ACROSS PORTIONS OF LINCOLN 
AND NORTHERN MOHAVE COUNTIES. OVERALL COVERAGE SHOULD BE MUCH LESS 
THAN YESTERDAY. THE CURRENT FORECAST HANDLES THIS AND OTHER WEATHER 
ELEMENTS WELL, NO UPDATES PLANNED AT THIS TIME. 
&&

.PREVIOUS DISCUSSION...
200 AM PDT THU OCT 22 2015

.SHORT TERM...THROUGH SATURDAY NIGHT.

UPPER LOW CONTINUES TO SPIN OVER CENTRAL ARIZONA THIS MORNING...BUT 
IS EXPECTED TO FINALLY OPEN UP AND SHIFT NORTHEAST BY LATE THIS 
AFTERNOON. WE WILL CONTINUE TO SEE SOME WRAP AROUND MOISTURE PUSH AS 
FAR WEST AS SOUTHERN NEVADA...BUT PRECIPITATION COVERAGE IS EXPECTED 
TO BE LESS THAN YESTERDAY AND MAINLY CONFINED TO NORTHERN MOHAVE 
COUNTY. CONDITIONS ARE ALSO A BIT MORE STABLE TODAY AND DID GO AHEAD 
AND REMOVE THUNDER FROM THE FORECAST. A FAST MOVING SHORTWAVE WILL 
QUICKLY MOVE INTO WESTERN PORTIONS OF THE CWA THIS AFTERNOON 
BRINGING A FEW HIGH CLOUDS TO THE REGION...BUT LITTLE ELSE. THIS 
WILL BE FOLLOWED BY A WEAK RIDGE OF HIGH PRESSURE FRIDAY WITH 
ANOTHER WEAK SHORTWAVE MOVING THROUGH THE REGION SATURDAY. 
AGAIN...WITH NOTHING MORE THAN A FEW HIGH CLOUDS. OVERALL 
TEMPERATURES WILL REMAIN JUST SLIGHTLY ABOVE NORMAL THROUGH 
SATURDAY. 

.LONG TERM...SUNDAY THROUGH WEDNESDAY. 

STILL HIGH CONFIDENCE IN DRY WEATHER SUNDAY AS OUR AREA IS UNDER 
SOUTHWEST FLOW AHEAD OF LOW PRESSURE ENTERING THE PACIFIC NORTHWEST. 
MODELS DISAGREE ON HOW TO EVOLVE THIS LOW...BUT ENOUGH ENSEMBLE 
MEMBERS SUPPORT A CHANCE OF PRECIP OVER THE NORTHERN ZONES MONDAY TO 
JUSTIFY SLIGHT CHANCE POPS. DRY WEATHER RETURNS TUESDAY UNDER 
RIDGING...THEN THE NEXT FEATURE OF INTEREST WILL BE THE STRONGER 
PACIFIC TROUGH NEARING THE WEST COAST WEDNESDAY. AS WAS THE CASE 
YESTERDAY...MODELS AGREE WELL ON THE EXISTENCE OF THIS TROUGH BUT 
DISAGREE ON STRENGTH...SPEED...AND WHETHER IT WILL SPLIT IN TWO OR 
NOT. SENSIBLE WEATHER EFFECTS ARE MOST LIKELY TO OCCUR JUST BEYOND 
THE END OF THIS FORECAST PERIOD...SO FOR NOW IT IS JUST SOMETHING TO 
KEEP IN MIND. FOR THE MOST PART TEMPERATURES SHOULD REMAIN NEAR TO 
SLIGHTLY ABOVE NORMAL THROUGH THE PERIOD...WITH POSSIBLE EXCEPTIONS 
OVER THE NORTHERN ZONES MONDAY IF RAIN OCCURS. 
&&

.AVIATION...FOR MCCARRAN...WINDS ARE EXPECTED TO REMAIN FAIRLY LIGHT 
THROUGH FRIDAY WITH TYPICAL DIURNAL WINDS UNDER 7KTS. FEW CLOUDS 
AROUND 8-10K FEET TODAY...BUT LESS COVERAGE FRIDAY WITH JUST A FEW 
HIGH CLOUDS. 

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST 
CALIFORNIA...A FEW SHOWERS ONCE AGAIN TODAY FOR NORTHERN MOHAVE 
COUNTY WITH MAINLY JUST FEW-SCT CLOUDS AROUND 8-10K FEET OVER 
LINCOLN AND CLARK COUNTIES. MOSTLY SUNNY CONDITIONS ELSEWHERE. WINDS 
WILL REMAIN UNDER 10KTS THROUGH FRIDAY. 
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION IS NOT EXPECTED. 
HOWEVER...SPOTTERS ARE ENCOURAGED TO REPORT ACCORDING TO STANDARD 
OPERATING PROCEDURES. 
&&

$$

UPDATE...PADDOCK 
SHORT TERM/AVIATION...GORELOW 
LONG TERM....MORGAN

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