Expires:No;;000001
FPUS55 KPSR 180258 RRA
ZFPPSR
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
800 PM MST SUN APR 17 2011
.SYNOPSIS...
SEVERAL WEAK PACIFIC LOW PRESSURE SYSTEMS WILL BRING LOWER 
TEMPERATURES AND BREEZY WEATHER AT TIMES THIS WEEK MAINLY DURING THE 
AFTERNOONS INTO THE EVENINGS. THE STRONGEST WINDS ARE EXPECTED MONDAY
AFTERNOON AND EARLY EVENING...ESPECIALLY IN SOUTHEAST CALIFORNIA. 
MOSTLY CLEAR NIGHTS AND SUNNY DAYS ARE EXPECTED THIS WEEK WITH SOME 
HIGH CLOUDS AT TIMES.
&&
.DISCUSSION...
THE STORM TRACK WILL REMAIN WELL TO THE NORTH OF AZ IN THE COMING 
DAYS...HOWEVER A PASSING DISTURBANCE WILL MOVE INTO NEVADA AND UTAH 
MONDAY. NO PRECIP IS EXPECTED MONDAY IN OUR FORECAST AREA...BUT 
WINDY CONDITIONS WILL DEVELOP BY LATE AFTERNOON AREA-WIDE. THE 
STRONGEST WESTERLY WINDS ARE EXPECTED OVER THE IMPERIAL VALLEY OF CA 
MONDAY AFTERNOON/EVENING WITH PEAK GUSTS NEAR 40 MPH. PEAK GUSTS 
BETWEEN 30 AND 35 MPH ARE ALSO POSSIBLE ALONG THE COLORADO RIVER AND 
OVER THE GREATER PHOENIX AREA. CURRENT FORECASTS LOOK OK. NO UPDATES 
REQUIRED. PREVIOUS DISCUSSION LOOKS OK.
PREVIOUS DISCUSSION...
HIGH PRESSURE ALOFT WAS STILL CENTERED WEST OF SOUTHERN BAJA 
CALIFORNIA. THIS HIGH PRESSURE SYSTEM HAS BEEN RESPONSIBLE FOR THE 
WELL ABOVE AVERAGE TEMPERATURES THIS WEEKEND. DESERT HIGHS WERE 
GENERALLY IN THE UPPER 90S TO NEAR 100 DEGREES IN MOST LOCATIONS 
SUNDAY.
THE DRY SOUTHERN END OF A PACIFIC LOW PRESSURE SYSTEM WAS CLOSING IN 
ON THE NORTHERN CALIFORNIA COAST SUNDAY AFTERNOON. THIS SYSTEM IS 
EXPECTED TO BRING LOWER TEMPERATURES AND BREEZY TO WINDY WEATHER 
ACROSS SOUTHEAST CALIFORNIA TO SOUTH-CENTRAL ARIZONA MONDAY 
AFTERNOON INTO MONDAY EVENING.
IT LOOKS AS IF WINDS WILL GET CLOSE TO THE THRESHOLD FOR A WIND 
ADVISORY IN SOUTHEAST CALIFORNIA MONDAY AFTERNOON INTO MONDAY 
EVENING...PARTICULARLY IN IMPERIAL COUNTY. THIS IS WHEN AND WHERE 
THE STRONGEST WINDS ARE EXPECTED THIS WEEK. HOWEVER...WIND SPEEDS 
MAY NOT QUITE REACH CRITERIA. THUS...HAVE NOT ISSUED A WIND ADVISORY 
ON THIS SHIFT.
LESS WIND IS EXPECTED TUESDAY AS RELATIVELY HIGHER PRESSURE ALOFT 
FROM THE PACIFIC MOVES EAST OVER OUR AREA.
THE DRY AND RELATIVELY WEAK SOUTHERN PORTIONS OF A SERIES OF PACIFIC 
LOW PRESSURE SYSTEMS ARE EXPECTED TO BRING AT LEAST BREEZY WEATHER AT
TIMES MAINLY DURING THE AFTERNOONS INTO THE EVENINGS WEDNESDAY 
THROUGH AT LEAST FRIDAY. THESE SYSTEMS ARE ALSO EXPECTED TO KEEP 
TEMPERATURES CLOSE TO OR SLIGHTLY ABOVE AVERAGE FOR MID TO LATE 
APRIL TUESDAY THROUGH AT LEAST FRIDAY.
MOSTLY CLEAR NIGHTS AND SUNNY DAYS ARE EXPECTED THIS WEEK WITH SOME 
HIGH CLOUDS AT TIMES.
THE FORECAST BECOMES SOMEWHAT MORE UNCERTAIN BY NEXT SUNDAY. THERE 
ARE SOME INDICATIONS THAT A DEEPER LOW PRESSURE SYSTEM FROM THE 
PACIFIC MAY MOVE INTO OUR AREA. HOWEVER...AGREE WITH PREVIOUS SHIFT 
THAT THIS IS PROBABLY OVERDONE...ESPECIALLY GIVEN THE TIME OF YEAR 
AS WE HEAD INTO OUR DRIEST TIME OF THE YEAR. THUS...THE BEST 
FORECAST...AT LEAST FOR THE TIME BEING IS TO SHOW A MODEST LOWERING 
OF TEMPERATURES SUNDAY COMPARED TO THE MID TO LATE WEEK FORECAST. 
ALSO...THERE MIGHT BE SOME MORE HIGH CLOUDINESS LATE FRIDAY AND NEXT 
WEEKEND...BUT THAT IS ABOUT IT AS FAR AS BEING DIFFERENT FROM THE 
MID TO LATE WEEK FORECAST THIS WEEK.
&&
.AVIATION...
SOUTH-CENTRAL AND SOUTHWEST ARIZONA AND SOUTHEAST CALIFORNIA... 
INCLUDING KPHX...KIWA...KIPL AND KBLH AIRFIELDS...
MOSTLY CLEAR SKIES WITH LIGHT WIND UNDER 10 KNOTS WILL CONTINUE 
THROUGH 19Z MON. BETWEEN 19Z MON AND 03Z TUE...INCREASING WEST WIND  
15 TO 30 KTS IS EXPECTED...AS THE TAIL END OF A DRY COLD FRONT MOVES 
THROUGH THE REGION. 
AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
&&
.FIRE WEATHER...
WEDNESDAY THROUGH SUNDAY...
A SERIES OF DRY LOW PRESSURE SYSTEMS WILL MOVE THROUGH THE REGION 
BRINGING OCCASIONAL HIGH CLOUDS AND COOLER TEMPERATURES. BREEZY 
CONDITIONS WILL PERSIST EACH AFTERNOON...SOUTHWEST WINDS IN THE 
10-20 MPH RANGE WITH LOCALLY HIGHER GUSTS. DAYTIME HUMIDITY LEVELS 
ARE EXPECTED TO DROP INTO THE TEENS...ALONG WITH FAIR OVERNIGHT 
RECOVERY THROUGH THE WEEK. HOWEVER...LOWER HUMIDITY VALUES MAY 
BRIEFLY OCCUR IN SOME AREAS...WHILE FUELS REMAIN DRY. COMBINE 
LOCALLY GUSTY UPSLOPE WINDS...AND THE POTENTIAL EXISTS FOR BRIEF 
PERIODS OF HAZARDOUS FIRE WEATHER CONDITIONS.   
&& 
 
.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...NONE. 
CA...NONE.
&&
$$
NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT
WEATHER.GOV/PHOENIX
DISCUSSION...VASQUEZ/ELLIS
AVIATION...VASQUEZ
FIRE WEATHER...SIPPLE