FXUS65 KPSR 212220
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
ISSUED BY NATIONAL WEATHER SERVICE LAS VEGAS NV
320 PM MST WED OCT 21 2009

.SYNOPSIS...DRY NORTHWEST FLOW WILL BE OVER THE REGION THROUGH THE 
REMAINDER OF THE WEEK AND INTO EARLY NEXT WEEK. MOSTLY CLEAR SKIES 
ARE EXPECTED WHILE TEMPERATURES WILL WARM TO A FEW DEGREES ABOVE 
NORMAL.      
&& 

.DISCUSSION...
IN THE SHORT TERM...DRY NORTHWEST FLOW WILL BE OVER THE FORECAST 
AREA THROUGH SATURDAY NIGHT BRINGING SOME THIN HIGH CLOUDS AT TIMES. 
OTHERWISE MOSTLY CLEAR SKIES AND LIGHTER WINDS CAN BE EXPECTED WITH 
TEMPERATURES WARMING TO A LITTLE ABOVE NORMAL.
&&

IN EXTENDED...HIGH PRESSURE REMAINS OFF SHORE SUNDAY AND MONDAY WITH 
DRY NORTHWEST FLOW OVER THE AREA. LITTLE CHANGE IN TEMPERATURES ARE 
EXPECTED AND WINDS WILL BE RELATIVELY LIGHT. THE UPPER FLOW 
TRANSITIONS TO WESTERLY AHEAD OF THE NEXT SHORTWAVE SLATED TO AFFECT 
THE REGION BY MID WEEK. SOUTHWEST WINDS ARE FORECAST TO INCREASE 
TUESDAY AS THE SYSTEM DROPS THROUGH THE GREAT BASIN AND THEN SHIFT 
TO THE NORTH WEDNESDAY AS A COLD FRONT PASSES THROUGH THE AREA. A 
DEGREE OR TWO OF COOLING EXPECTED TUESDAY AS 500MB HEIGHTS DECREASE 
AHEAD THE SYSTEM WITH A DECENT LOWERING OF TEMPERATURES FOR 
WEDNESDAY...5 OR MORE DEGREES...AS THE COLD FRONT DROPS INTO THE 
REGION. LITTLE TO NO PRECIPITATION ANTICIPATED WITH THIS EVENT 
PROVIDED A MORE WESTERLY TRACK AND A DEEPER SYSTEM DO NOT CHANGE 
THIS PER THE 12Z GEM SOLUTION.   
&&

.AVIATION...
KPHX/KIWA AND SURROUNDING AIRFIELDS...
LIGHT WINDS ARE EXPECTED OVER MOST OF SOUTH-CENTRAL ARIZONA AND 
SOUTHEAST CALIFORNIA OVER THE NEXT COUPLE OF DAYS. NORTH WINDS NEAR 
10 KTS ARE POSSIBLE ALONG THE LOWER COLORADO RIVER VALLEY THURSDAY 
MORNING BUT ARE EXPECTED TO DIMINISH IN THE AFTERNOON. FEW-SCT 
CIRRUS AOA 25KFT THIS AFTERNOON AND EVENING WITH CLEAR CONDITIONS 
THURSDAY. NO AVIATION WEATHER CONCERNS ARE EXPECTED.

AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.
&&

.FIRE WEATHER...DRY NORTHWEST FLOW WILL BE OVER THE AREA THROUGH 
EARLY NEXT WEEK. WINDS WILL GENERALLY BE LIGHT WHILE RELATIVE 
HUMIDITY VALUES DURING THE DAYS WILL DROP BELOW 15 PERCENT IN MOST 
AREAS. TEMPERATURES WILL BE A LITTLE ABOVE NORMAL. 
&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE

&&

$$

NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT

WEATHER.GOV/PHOENIX

SHORT TERM...HARRISON
LONG TERM...SALMEN
AVIATION...SALMEN