AREA FORECAST DISCUSSION

 
 FXUS65 KPSR 240211
 AFDPSR
 
 AREA FORECAST DISCUSSION
 NATIONAL WEATHER SERVICE PHOENIX AZ
 715 PM MST MON NOV 23 2009
 
 .SYNOPSIS...
 MOSTLY CLEAR NIGHTS AND SUNNY DAYS ARE EXPECTED TO CONTINUE THROUGH 
 THANKSGIVING DAY. HIGH PRESSURE ALOFT BETWEEN HAWAII AND BAJA 
 CALIFORNIA WILL BUILD NORTHEAST OVER OUR AREA WITH WARMER WEATHER 
 WEDNESDAY AND THANKSGIVING DAY. TEMPERATURES WILL RISE TO WELL ABOVE 
 AVERAGE FOR LATE NOVEMBER BY THANKSGIVING DAY...IN THE UPPER 70S TO 
 NEAR 80 DEGREES IN THE DESERT AREAS INCLUDING PHOENIX...YUMA AND
 EL CENTRO. A NORTH PACIFIC LOW PRESSURE SYSTEM IS EXPECTED TO MOVE 
 SOUTHEAST ACROSS ARIZONA AND BRING MUCH COOLER WEATHER TO OUR AREA BY
 SUNDAY. IT WILL ALSO BE WINDY THIS WEEKEND. THE STRONGEST WINDS ARE 
 EXPECTED DOWN THE LOWER COLORADO RIVER VALLEY ESPECIALLY BY SUNDAY.
 
 &&
 
 .DISCUSSION...
 VERY LITTLE CHANGE IN THE WEATHER PATTERN IS EXPECTED THROUGH 
 FRIDAY...I.E. SOME HIGH CLOUDS AT TIMES WITH LITTLE DAY TO DAY 
 CHANGE IN TEMPERATURE.
 
 HOWEVER...A BIG CHANGE TO COLD AND UNSETTLED WEATHER IS EXPECTED IN 
 AZ THIS WEEKEND AS EXPLAINED IN THE PREVIOUS DISCUSSION BELOW.  
 
 OTHERWISE CURRENT DRY FORECASTS THROUGH THANKSGIVING DAY LOOK OK. NO 
 UPDATES NECESSARY. 
 
 PREVIOUS DISCUSSION...
 MOSTLY CLEAR NIGHTS AND SUNNY DAYS ARE EXPECTED TO CONTINUE THROUGH 
 THANKSGIVING DAY. HIGH PRESSURE ALOFT BETWEEN HAWAII AND BAJA 
 CALIFORNIA WILL BUILD NORTHEAST OVER OUR AREA WITH TEMPERATURES 
 RISING TO WELL ABOVE AVERAGE FOR LATE NOVEMBER BY THANKSGIVING DAY. 
 HIGHS IN THE DESERT AREAS INCLUDING PHOENIX...YUMA AND EL CENTRO ARE 
 EXPECTED TO BE IN THE UPPER 70S TO NEAR 80 DEGREES BY THANKSGIVING 
 DAY WITH LITTLE CHANGE FRIDAY.
 
 A STRONG NORTH PACIFIC LOW PRESSURE SYSTEM IS EXPECTED TO MOVE INTO 
 ARIZONA SATURDAY NIGHT AND SUNDAY...WITH MUCH COLDER WEATHER FOR THE 
 AREA BY SUNDAY. IT WILL ALSO BE WINDY. THE STRONGEST WINDS ARE 
 EXPECTED DEVELOP DOWN THE LOWER COLORADO RIVER VALLEY ESPECIALLY 
 SATURDAY NIGHT AND SUNDAY. A WIND ADVISORY MAY BE NEEDED FOR 
 PORTIONS OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...ESPECIALLY 
 THE LOWER COLORADO RIVER VALLEY BY SATURDAY NIGHT AND SUNDAY. THIS 
 SYSTEM LOOKS AS IF IT WILL BE MOSTLY DRY FOR OUR AREA...WITH 
 PRECIPITATION EXPECTED OVER NORTHERN AND EASTERN AZ...INCLUDING 
 EASTERN PORTIONS OF OUR MOUNTAINOUS ZONE 24...SOUTHERN GILA COUNTY.
 
 &&
 
 .AVIATION...
 SOUTHEAST CA...SOUTHWEST AND SOUTH CENTRAL AZ...INCLUDING KIPL... 
 KBLH...KPHX...AND KIWA.
 
 MOSTLY CLEAR SKIES AND LIGHT WIND ARE EXPECTED AT THE ABOVE TAF 
 SITES THROUGH AT LEAST 03Z WED. THE ONLY EXCEPTION IS THE COLORADO 
 RIVER VALLEY NEAR KBLH WHERE AFTERNOON NORTH WINDS OF 12 TO 22 KNOTS 
 ARE EXPECTED BETWEEN 20Z TUE AND 01Z WED.
 
 AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.
 
 &&
 
 .FIRE WEATHER...
 WEDNESDAY THROUGH SUNDAY...
 HIGH PRESSURE ALOFT WILL DOMINATE THE WEATHER PATTERN WEDNESDAY AND 
 THANKSGIVING DAY...WITH MOSTLY CLEAR OR CLEAR SKIES EXPECTED EACH 
 DAY...AND RELATIVELY LIGHT WINDS. HIGH TEMPERATURES WILL CONTINUE 
 WELL ABOVE AVERAGE FOR LATE NOVEMBER...ALONG WITH VERY DRY AIR. MANY 
 DESERT LOCATIONS WILL HAVE MINIMUM RELATIVE HUMIDITY WELL BELOW 15 
 PERCENT OR IN THE SINGLE DIGITS...WITH MODEST RECOVERY AT NIGHT.
 
 A NORTH PACIFIC LOW PRESSURE SYSTEM WILL BRING SIGNIFICANT COOLING 
 BY THIS WEEKEND WITH INCREASING WIND. HIGH TEMPERATURES MAY FALL 
 AROUND 15 DEGREES BY SUNDAY COMPARED WITH THE PEAK HIGH TEMPERATURES 
 THANKSGIVING DAY. HIGHS SUNDAY ARE EXPECTED TO BE IN THE MID 60S IN 
 MOST LOWER ELEVATION DESERT LOCATIONS. THIS WILL BE A RATHER DRY 
 SYSTEM FOR OUR AREA...BUT RELATIVE HUMIDITY WILL BE HIGHER MOSTLY 
 BECAUSE OF THE COOLING.
 
 IT WILL BE WINDY THIS WEEKEND. WINDS WILL BE QUITE STRONG IN PORTIONS
 OF SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA. THE STRONGEST WINDS 
 ARE EXPECTED DOWN THE LOWER COLORADO RIVER VALLEY ESPECIALLY 
 SATURDAY NIGHT AND SUNDAY.
 
 &&
 
 .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...ELLIS
 
 
 
 
 
 

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