Severe Thunderstorm Warning 3, NWS Tucson, AZ

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
230 PM MST FRI JUN 22 2001

SYNOPSIS...HIGH PRESSURE WILL REMAIN POSITIONED OVER THE AREA INTO
NEXT WEEK...WITH A STEADY FETCH OF MOISTURE FROM THE SOUTH. THIS
MOISTURE SUPPLY IN COMBINATION WITH DAYTIME HEATING WILL LEAD TO A
CONTINUED THREAT OF AFTERNOON AND EVENING THUNDERSTORMS. A LOW
PRESSURE TROUGH DEVELOPING ALONG THE WEST COAST EARLY NEXT WEEK
SHOULD BRING A DRIER SOUTHWESTERLY FLOW TO PART OF THE AREA...
RESULTING IN A DECREASE IN THUNDERSTORMS FROM THE WEST.

DISCUSSION...500MB THETA-E RIDGE ACROSS NORTHWEST MEXICO INTO
WESTERN ARIZONA...WITH MAIN FOCUS OF 700MB THETA-E RIDGE ACROSS
EASTERN ARIZONA. PRECIPITABLE WATER VALUES RANGING FROM AROUND 1
INCH FAR EAST TO AN INCH AND A HALF. MOUNTAIN BUILDUPS HAVE STARTED
ON TIME AND INITIAL FORAYS INTO VALLEYS HAVE BEEN UNIMPRESSIVE...SO
FAR THAT IS. WEVE SEEN A LITTLE DRYING IN THE FAR SOUTHEAST...BUT
MOST OF THE AREA IS HOLDING ON WITH DEEP ENOUGH MOISTURE TO REACT
WELL TO OUTFLOW INITIATED OFF HIGHER TERRAIN. GETTING PLENTY OF
HEATING AS WELL. SHOULD HAVE NO PROBLEM WITH A HEAVY SCATTERED
THUNDERSTORM COVERAGE THIS AFTERNOON AND EVENING WITH ONE OR TWO
STORMS WORTHY OF MENTION...CERTAINLY A BIT BUSIER THAN YOUR TYPICAL
JUNE 22 AFTERNOON.

NO MUCH TO CHANGE UNTIL TROUGH DIGS A LITTLE UPSTREAM AND DRIER
SOUTHWESTERLY FLOW INCREASES IN THE WEST. THUNDERSTORMS LIKELY
RETREATING BACK TO AN EMPHASIS ON EASTERN MOUNTAINS.

.TWC...NONE.

AZZ019-029>035-230700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
12 NOON MST FRI JUN 22 2001

.SYNOPSIS...THE COMBINATION OF AMPLE MOISTURE...GOOD SURFACE HEATING
AND AN UNSTABLE ATMOSPHERE WILL RESULT IN ANOTHER DAY OF AFTERNOON
AND EVENING THUNDERSTORMS ACROSS SOUTHEAST ARIZONA. THE FOCUS FOR
THE CHANCE OF SEVERE WEATHER TODAY WILL BE FROM TUCSON EAST...WHERE
STRONG DOWNBURST WINDS WILL BE THE PRIMARY THREAT.

.DISCUSSION...NOT MUCH HAS CHANGED FROM THURSDAY AS THE ATMOSPHERE
CONTINUES TO BE MOIST AND UNSTABLE. ISOLATED THUNDERSTORMS WILL BE
DEVELOPING BETWEEN 1 PM AND 3 PM OVER THE HIGHER TERRAIN EAST OF
TUCSON AND SHOW LITTLE MOVEMENT. HOWEVER BY LATE IN THE AFTERNOON
THEY WILL START TO MOVE OFF THE MOUNTAINS AND INTO THE VALLEY AREAS
AND BECOME SCATTERED IN NATURE THROUGH THE EVENING HOURS. THE
WESTERN DESERTS WILL SEE SOME THUNDERSTORM ACTIVITY AFTER SUNSET.
THE MAIN THREAT FROM THE STORMS WILL BE STRONG DOWNBURST WINDS WITH
GUSTS TO 50 MPH POSSIBLE. THE THREAT FROM FLASH FLOODING TODAY IS
MINIMAL.

STORM MOVEMENT WILL BE WEST-NORTHWEST AT 10 TO 15 MPH.