000
FXUS65 KPSR 111014
AFDPSR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
314 AM MST THU MAR 11 2010

.UPDATE...UPDATED AVIATION AND FIRE WEATHER DISCUSSSIONS

&&

.SYNOPSIS...
LOW PRESSURE WILL CONTINUE MOVING TO THE EAST...TAKING ALL THE
SHOWERS WITH IT TODAY...AND SUNNY SKIES WILL RETURN ON THE DESERTS.
HIGH PRESSURE WILL DOMINATE OUR AREA AND KEEP DRY AND WARMER WEATHER
INTO SATURDAY. ANOTHER LOW PRESSURE SYSTEM FROM THE NORTHWEST WILL
BRING A CHANCE OF SHOWERS EAST OF PHOENIX SUNDAY AND SUNDAY NIGHT.
EXPECT SUNNY AND WARMER WEATHER AGAIN EARLY NEXT WEEK.

&&

.DISCUSSION...
LINE OF LIGHT SHOWERS AND GUSTY WINDS MOVED THROUGH METRO PHOENIX
BEFORE MIDNIGHT...AS THE POCKET OF COLD AIR ALOFT DRIFTED SOUTHEAST.
LAST EVENINGS SOUNDINGS INDICATED -28 TO -30C AT 500 MB WITH A 100
KT JET CORE ACROSS WESTERN AZ. UPSTREAM RIDGE NEAR THE COAST APPEARS
TO BE BUILDING SOMEWHAT FASTER THAN MODELS INDICATED YESTERDAY
MORNING. MUCH DRIER AIR WILL ALSO FILTER INTO THE DESERTS ALONG
WITH CLEAR SKIES.

WESTERN RIDGE PROGGED TO SPREAD ACROSS CALIFORNIA AND ARIZONA THE
NEXT COUPLE DAYS. LATEST GFS SHOWS THE UPPER RIDGE AXIS OVER SOUTH
CENTRAL ARIZONA ON FRIDAY. IT ALSO HAS BEEN CONSISTENT IN SPLITTING
THE UPSTREAM TROUGH...AND CARVING OUT ANOTHER CLOSED LOW IN NEVADA
BY SATURDAY AFTERNOON. INTERESTINGLY...ECMWF AGREES IN GOOD
AGREEMENT ON THE TIMING OF THIS LOW...WITH A BIT LOWER HEIGHTS THAN
SHOWN BY GFS. IN ANY CASE...WE NOW HAVE BETTER CONFIDENCE IN
BOOSTING OUR CHANCES FOR SOME LIGHT PRECIP FOR OUT EASTERN ZONES ON
SUNDAY...AND SUNDAY NIGHT.

TEMPS REBOUND AGAIN EARLY NEXT WEEK...BUT NOT EXPECTING A DRAMATIC
WARM-UP. THIS SLOWER WARMING TREND MAY BE A BLESSING IN DISGUISE
THAT WILL LEAD TO A GRADUAL DROP IN THE SNOWPACK ACROSS EASTERN AND
NORTHERN ARIZONA. IN ANY CASE...LOOK FOR HIGHS ACROSS OUR LOWER
DESERTS TO WARM THE MOST...HIGHS COULD TOP OUT IN THE LOW TO MID 80S
ALONG THE LOWER COLORADO RIVER AND INTO SOUTHEAST CALIFORNIA BY
TUESDAY OR WEDNESDAY.

&&

.AVIATION...
SOUTHEAST CALIFORNIA AND SOUTHWEST AZ...INCLUDING KIPL AND KBLH...
THROUGH 03Z FRI...CLEAR SKIES...BUT NORTHWEST WINDS 10 TO 20 KNOTS
THROUGH 03Z FRI.

SOUTH CENTRAL AZ INCLUDING KPHX AND KIWA...
THROUGH 03Z FRI...CLEAR SKIES...BUT NORTHWEST WINDS 5 TO 15 KNOTS
THROUGH 03Z FRI.

AVIATION DISCUSSION NOT UPDATED FOR AMENDED TAFS.

&&

.FIRE WEATHER...
SATURDAY THROUGH MONDAY...
A HIGH PRESSURE SYSTEM WILL BUILD INTO THE REGION FRIDAY NIGHT AND
SATURDAY...RESULTING IN WARMER TEMPERATURES. HUMIDITY LEVELS WILL
ALSO REMAIN LOW UNDER DRY NORTHERLY WINDS FROM NEVADA AND UTAH.
HOWEVER...LATE SATURDAY AND SUNDAY ANOTHER PACIFIC LOW PRESSURE
SYSTEM WILL MOVE QUICKLY ACROSS THE REGION RESULTING IN BREEZY TO
WINDY CONDITIONS AND COOLER TEMPERATURES. THERE IS A SLIGHT CHANCE
OF SHOWERS SUNDAY OVER SOUTHERN GILA COUNTY.  A STRONG HIGH PRESSURE
SYSTEM WITH MUCH WARMER TEMPERATURES SHOULD RETURN MONDAY.


&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.

CA...NONE.

&&

$$

NATIONAL WEATHER SERVICE PHOENIX IS ON THE INTERNET AT

WEATHER.GOV/PHOENIX

DISCUSSION...SIPPLE
AVIATION...VASQUEZ
FIRE WEATHER...VASQUEZ

NWS PSR Office Area Forecast Discussion