Severe Thunderstorm Warning 22, NWS Phoenix, AZ

AZZ020>028-CAZ030>033-300545-

SOUTHWEST ARIZONA/SOUTHEAST CALIFORNIA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE PHOENIX AZ
250 PM MST TUE JUL 29 2003

.SYNOPSIS...
HIGH PRESSURE WILL REMAIN OVER NORTHERN CALIFORNIA AND NEVADA
ANOTHER DAY BEFORE MIGRATING TOWARDS THE FOUR CORNERS REGION MID
WEEK...AND OVER NEW MEXICO BY THE WEEKEND. MEANWHILE...A CLOSED LOW
PRESSURE SYSTEM WILL CONTINUE TO MOVE WESTWARD ACROSS THE BAJA
PENINSULA...AND THEN NORTHWARD TOWARDS SOUTHERN CALIFORNIA BY
FRIDAY. THERE WILL BE A CONTINUED CHANCE OF MAINLY AFTERNOON SHOWERS
AND THUNDERSTORMS EACH DAY THROUGH FRIDAY. DRYING IS POSSIBLE BY THE
WEEKEND...WITH A TYPICAL LOW-GRADE MONSOON FORECAST IN PLACE THROUGH
THE EARLY PART OF NEXT WEEK.

.DISCUSSION...
SAT IMAGERY AND RADAR PICS THIS AFTERNOON SHOW THUNDERSTORM
DEVELOPMENT ALONG THE MOGOLLON RIM AND OVER YAVAPAI COUNTY...YET
THINGS APPEAR TO BE SLOW TO GET GOING OVER SOUTHEAST AND EASTERN AZ
(AND RIGHTFULLY SO AFTER TWO RATHER ACTIVE WEATHER DAYS). FLOW ALOFT
REMAINS OUT OF THE EAST OVER CENTRAL AZ AND OUT OF THE SOUTHEAST
OVER SOUTHEASTERN AZ. THUS...ANY ACTIVITY WE GET IN THE LOWER
DESERTS TONIGHT WILL LIKELY BE AFTER SUNSET.

A QUICK RE-CAP OF THE CURRENT SYNOPTIC PATTERN HAS A CLOSED LOW
CIRCULATION OFF THE BAJA PENINSULA...AND A STRONG UPPER LEVEL HIGH
OVER NRN CA. DISTURBANCES CONTINUE TO ROTATE AROUND BOTH OF THESE
LARGE SCALE FEATURES...WITH ANOTHER AREA OF UPPER LEVEL DIVERGENCE
PROGED TO ROTATE THROUGH NRN AZ AND INTO SE CA THIS
AFTERNOON/EVENING...WHILE A SECOND DISTURBANCE ROTATES AROUND THE
CLOSED LOW AND ACROSS NRN MEX. THE THUNDERSTORMS PARTIALLY INITIATED
BY THESE TWO FEATURES COULD MEET UP OVER SOUTHEAST CALIFORNIA...
SOUTHWEST AND SOUTH-CENTRAL ARIZONA FOR A RATHER ACTIVE EVENING OVER
OUR CWA. HAVE INCREASED THE POPS OVERNIGHT FOR OUR WRN ZONES TO
CARRY A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS THROUGHOUT THE
EVENING HOURS. WILL GO WITH A SLIGHT CHANCE OF SHOWERS AND
THUNDERSTORMS OVER SOUTHEAST CALIFORNIA AND SOUTHWEST ARIZONA...AND
SCATTERED SHOWERS AND THUNDERSTORMS OVER THE SOUTH-CENTRAL DESERTS
AND HIGHER TERRAIN (POSSIBLY OVER AZ ZONE 21 AS WELL AS SCATTERED
SHOWERS AND THUNDERSTORMS OVER YAVAPAI COUNTY CONTINUE TO DRIFT
SOUTHWEST).

BEYOND TONIGHT...LOOKS LIKE THE CLOSED LOW WILL CONTINUE TO MIGRATE
NORTH AND WEST...WHILE THE HIGH SHIFTS BACK EASTWARD. NOT A LOT IN
THE WAY OF UPPER LEVEL DYNAMICS PROGED FOR WED ...AND WILL GO WITH A
SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS SOUTH-CENTRAL AZ...PARTLY
SUNNY ELSEWHERE. BY THU...THE HIGH IS LOCATED OVER NRN NEW MEXICO
WITH THE LOW JUST OFF THE SRN CA COAST. THIS SYNOPTIC PATTERN WILL
RESULT IN A SOUTHERLY FLOW OVER ARIZONA...WHICH COULD INCREASE
MOISTURE OVER THE STATE AS SEVERAL DISTURBANCES ARE PROGED BY THE
MODELS TO WORK THEIR WAY ACROSS MEXICO...AND UP INTO ARIZONA DURING
THE THU/FRI TIME FRAME. BEYOND FRI...THE GFS SUGGESTS SOME DRYING
OVER OUR WRN CWA AS THE FLOW BECOMES SOUTHWESTERLY. FOR NOW...WILL
GO WITH A STANDARD LOW GRADE MONSOON FORECAST SAT THROUGH TUE.  LW

.PSR...NONE.

AZZ020>028-CAZ030>033-300100-

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE PHOENIX AZ
600 AM MST TUE JUL 29 2003

THIS HAZARDOUS WEATHER OUTLOOK IS FOR SOUTHWEST AND
SOUTH-CENTRAL ARIZONA...AND SOUTHEAST CALIFORNIA.

.DAY ONE...TODAY

THUNDERSTORMS WILL BE DEVELOPING OVER THE HIGHER TERRAIN OF SOUTH
CENTRAL ARIZONA THIS AFTERNOON AND EVENING...AND OVER ALL THE DESERT
AREAS FROM SOUTH CENTRAL ARIZONA WESTWARD THROUGH SOUTHEAST
CALIFORNIA LATER THIS AFTERNOON AND THIS EVENING. SOME OF THESE
THUNDERSTORMS MAY PRODUCE LOCALLY HEAVY RAINS AND STRONG GUSTY
DAMAGING WINDS...ESPECIALLY DURING THIS EVENING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.