Severe Thunderstorm Warning 12, NWS Phoenix, AZ

AZZ020>028-CAZ030>033-240545-

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
330 PM MST SAT APR 23 2005

SOUTHWEST AND SOUTH-CENTRAL ARIZONA...AND SOUTHEAST CALIFORNIA
FORECAST DISCUSSION

.SYNOPSIS...
A LOW PRESSURE SYSTEM WILL MOVE NORTHEAST ACROSS SOUTHERN CALIFORNIA
AND ARIZONA TONIGHT. THIS SYSTEM WILL BRING WINDY WEATHER TO THE
ENTIRE AREA...AND SCATTERED SHOWERS AND THUNDERSTORMS WITH AREAS OF
BLOWING DUST MAINLY EAST OF THE LOWER COLORADO RIVER AND ESPECIALLY
TO SOUTH-CENTRAL ARIZONA INCLUDING THE GREATER PHOENIX AREA THROUGH
TONIGHT. THEN...COOLER AND BREEZY TO WINDY WEATHER IS EXPECTED BEHIND
THIS SYSTEM SUNDAY. DRY AND WARMER WEATHER IS EXPECTED BY MONDAY
THROUGH WEDNESDAY AS HIGH PRESSURE ALOFT FROM THE PACIFIC MOVES EAST
OVER THE SOUTHWESTERN UNITED STATES. ANOTHER PACIFIC LOW PRESSURE
SYSTEM IS EXPECTED TO BRING COOLER AND BREEZY TO WINDY WEATHER WITH
A CHANCE OF SHOWERS BY THURSDAY NIGHT INTO FRIDAY.

&&

.DISCUSSION...
TEMPERATURES WERE GENERALLY 5 TO 7 DEGREES WARMER AND DEW POINT
TEMPERATURES 20 TO 30 DEGREES HIGHER ALONG THE LOWER COLORADO RIVER
VALLEY INCLUDING YUMA EASTWARD ACROSS SOUTH-CENTRAL ARIZONA
INCLUDING THE GREATER PHOENIX AREA AT MID AFTERNOON TODAY COMPARED
WITH THE SAME TIME YESTERDAY. ISOLATED SHOWERS AND THUNDERSTORMS
DEVELOPED OVER THIS AREA DURING THE AFTERNOON. MEANWHILE...MID AND
HIGH LEVEL CLOUDINESS FROM THE SOUTH MOVED OVER SOUTHEAST CALIFORNIA
RESULTING IN TEMPERATURES THAT WERE 2 OR 3 DEGREES COOLER AT MID
AFTERNOON TODAY COMPARED WITH THE SAME TIME YESTERDAY. AND DEW POINT
TEMPERATURES WERE 10 TO 20 DEGREES HIGHER THERE.

A LOW PRESSURE SYSTEM THAT WAS JUST OFF THE NORTHERN BAJA CALIFORNIA
COAST AT MID AFTERNOON TODAY WILL MOVE NORTHEAST ACROSS SOUTHERN
CALIFORNIA AND ARIZONA TONIGHT. THIS SYSTEM WILL BRING WINDY WEATHER
TO THE ENTIRE AREA AND A CHANCE OF SHOWERS AND THUNDERSTORMS WITH
AREAS OF BLOWING DUST MAINLY EAST OF THE LOWER COLORADO RIVER VALLEY
AND ESPECIALLY TO SOUTH-CENTRAL ARIZONA LATE THIS AFTERNOON AND
TONIGHT.

MAIN CONCERN FOR THE SHORT TERM FORECAST IS THE INCREASING
THUNDERSTORMS WITH BRIEF HEAVY RAIN...STRONG GUSTY WINDS AND AREAS
OF BLOWING DUST ESPECIALLY IN SOUTH-CENTRAL ARIZONA THROUGH TONIGHT.
THE WIND WITH SOME THUNDERSTORMS COULD BECOME MARGINALLY SEVERE.
ALTHOUGH NOT MENTIONED IN THE FORECAST...SMALL HAIL IS ALSO
POSSIBLE. ALSO...WINDS MAY REACH MARGINAL LEVELS FOR WIND ADVISORY
CRITERIA IN SOUTHEAST CALIFORNIA AND FAR SOUTHWEST ARIZONA THIS
EVENING.

COOLER AND BREEZY TO WINDY WEATHER IS EXPECTED BEHIND THIS SYSTEM
SUNDAY...AND THERE IS A SLIGHT CHANCE OF SHOWERS AND AFTERNOON
THUNDERSTORMS OVER THE HIGHER TERRAIN OF SOUTH-CENTRAL ARIZONA.

DRY AND WARMER WEATHER IS EXPECTED BY MONDAY THROUGH WEDNESDAY AS
HIGH PRESSURE ALOFT FROM THE PACIFIC MOVES EAST OVER THE SOUTHWESTERN
UNITED STATES.

ANOTHER PACIFIC LOW PRESSURE SYSTEM IS EXPECTED TO BRING COOLER AND
BREEZY TO WINDY WEATHER WITH A CHANCE OF SHOWERS BY THURSDAY NIGHT
INTO FRIDAY.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...

AZ...NONE.
CA...NONE.

&&

ELLIS

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