Severe Thunderstorm Warning 11, NWS Tucson, AZ

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
245 PM MST WED JUL 4 2001

SYNOPSIS...ISOLATED TO SCATTERED AFTERNOON AND EVENING THUNDERSTORMS
WILL CONTINUE FOR THE REMAINDER OF THE WEEK AND INTO THE WEEKEND.
HIGH PRESSURE TO OUR NORTH AND NORTHEAST WILL GUIDE INCREASING
MOISTURE ACROSS SOUTHEAST ARIZONA...WITH THE THREAT OF HEAVY RAIN
ALSO INCREASING AS THE WEEK PROGRESSES.

DISCUSSION...UPPER AIR PLOTS THIS MORNING SHOWED THE 500 MB HIGH
CENTERED IN SOUTH-CENTRAL UTAH WITH STRONG EASTERLY FLOW ACROSS THE
AREA. THERE IS A WEAK INVERTED TROF IN NE NEW MEXICO AND AN EASTERLY
WAVE OVER THE TEXAS BIG BEND. TUCSON MORNING SOUNDING A TAD BIT MORE
MOIST WITH A DEEP EASTERLY WIND PROFILE. THE DIFFERENCE FROM
YESTERDAY IS THAT STORMS WILL BE MOVING WEST-NORTHWEST...INSTEAD OF
SOUTHWEST...AND WILL BE SCREAMING AROUND 20-25 MPH. GOES-10
PRECIPITABLE WATER PLOT THIS MORNING SHOWED HIGHEST VALUES WEST OF
TUCSON (GREATER THAN 1.50") AND LESS EAST OF TUCSON (LESS THAN 1").
THE HIGHER VALUES ARE DEPICTED ON SURFACE DEWPOINT WITH VALUES UP 10
OR MORE DEGREES FROM TUCSON WEST. 700 MB THETA-E RIDGE THIS
AFTERNOON SHOULD SETS UP JUST EAST OF TUCSON THIS AFTERNOON. AS
MENTIONED THIS MORNING...I AM NOT EXPECTING MUCH ACTIVITY THIS
EVENING EAST OF TUCSON DUE TO THE DRIER AIR. FROM TUCSON WEST...THE
MAIN THREAT THIS EVENING WILL BE STRONG WINDS. EVEN WITH THE HIGHER
PW VALUES IN THE LOWER DESERTS...THE FLASH FLOOD POTENTIAL IS LOW
SINCE THE STORMS WILL BE MOVING QUICKLY...AS STATED ABOVE... THAT
DOESN'T MEAN THERE WILL NOT BE LOCALIZED HEAVY RAIN OUT WEST WITH
SUCH HIGH MOISTURE VALUES.

THE NEXT TWO DAYS WILL BE INTERESTING IN THAT A SUBTROPICAL WEATHER
SYSTEM...CURRENTLY OFF SOUTHERN TIP OF BAJA...MOVES NORTHWEST JUST
WEST OF BAJA. THIS SYSTEM WILL BACK OUR UPPER WINDS FROM EASTERLY TO
A SOUTHERLY DIRECTION THURSDAY NIGHT AND FRIDAY...BRINGING AN
ABUNDANT AMOUNT OF MOISTURE WITH IT. THERE IS THE POTENTIAL FOR
LOCALLY HEAVY RAIN FROM TUCSON WEST THURSDAY NIGHT AND FRIDAY WHERE
THE DEEPEST MOISTURE WILL RESIDE. TEMPERATURES WILL BE A BIG
CHALLENGE ON FRIDAY DUE TO THE AMOUNT OF CLOUDINESS AND
SHOWER/THUNDERSTORM ACTIVITY. WILL CONTINUE THE STANDARD MONSOON
FORECAST NEST WEEK.

.TWC...NONE.

AZZ019-029>035-050700-

SOUTHEAST ARIZONA HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1145 AM MST WED JUL 4 2001

.SYNOPSIS...A STRONG EASTERLY FLOW REMAINS ACROSS SOUTHEAST ARIZONA
TODAY. LOW LEVEL MOISTURE INCREASED OVERNIGHT MAINLY FROM TUCSON
WEST. THUNDERSTORMS ARE EXPECTED TO DEVELOP OVER THE MOUNTAINS WITH
SOME COMING INTO THE VALLEY TOWARD EVENING...AND MAINLY WEST OF
TUCSON. WITH THE STRONG EASTERLY WINDS THE THUNDERSTORMS WILL BE
FAST MOVING.

.DISCUSSION...LOW LEVEL MOISTURE SURGED INTO THE AREA OVERNIGHT
AND MAINLY FROM THE SANTA CRUZ VALLEY WESTWARD. THEREFORE FOR
TODAY THE DEEPER MOISTURE IS LOCATED FROM TUCSON WEST. LOOK FOR
ISOLATED THUNDERSTORMS EAST OF TUCSON LATER TODAY WITH SCATTERED
THUNDERSTORMS DEVELOPING OVER THE MOUNTAINS AND MOVING INTO THE
VALLEYS WEST OF TUCSON. THE MID AND UPPER WINDS ARE STRONG OUT OF
THE EAST WHICH MEANS THUNDERSTORMS WILL BE MOVING QUICKLY...MAKING
THE MAIN THREAT DAMAGING WINDS. WITH THE STORMS SPEED THE THREAT
OF FLASH FLOODING WILL BE MUCH LESS.

STORM MOTION WILL BE TOWARDS THE WEST AT 15 TO 20 MPH.