Severe Thunderstorm Warning 44, NWS Tucson, AZ

SOUTHEAST ARIZONA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
930 AM MST SUN JUL 25 1999

SYNOPSIS...HIGH PRESSURE ALOFT SHIFTING WESTWARD FROM THE CENTRAL
PLAINS TO NEAR THE 4 CORNERS AREA BY MONDAY. REMAINS OF THE
EASTERLY WAVE THAT PUSHED THROUGH YESTERDAY NOW EXTENDS FROM EXTREME
SOUTHWEST ARIZONA NORTHEAST TO 4 CORNERS AREA. SOUTHEAST ARIZONA HAS
CLEARED OUT CONSIDERABLY THIS MORNING IN THE WAKE OF YESTERDAYS
ACTIVITY. SATELLITE IMAGE SHOWS SOME DRIER AIR MOVING SOUTHWEST INTO
NORTHERN GREENLEE COUNTY. THIS CONSISTENT WITH THE LITTLE CONVECTION
THIS AREA RECEIVED YESTERDAY. THUS LIKELY SEE EVEN LESS CONVECTIVE
ACTIVITY EASTERN SECTIONS TODAY. LIKELY SEE SOME INCREASE IN STORM
ACTIVITY MONDAY AS UPPER HIGH GETS CLOSER AND LIKLY SMALL INCREASE
IN MID/UPPER LEVEL MOISTURE FROM EAST.

DISCUSSION...SOUTHEAST ARIZONA STARTING OUT THIS MORNING WITH MOSTLY
CLEAR SKIES. SHOULD SEE FAIRLY RAPID HEATING HEATING.
HOWEVER...PLENTY OF LOW LEVEL MOISTURE AND CLOUDS ALREADY FORMING
NEAR MOUNTAINS. ONCE TEMPERATURE GETS PAST MID 80S IT WILL BE SLOW
GOING AS CONVECTIVE CLOUDS INCREASE. WINDS ALOFT CHANGED
CONSIDERABLY FROM YESTERDAY. THE LIGHT WINDS OF YESTERDAY ARE NOW
MODERATE STRONG SOUTHERLY WINDS ABOVE 30K FEET. THESE WINDS WILL
HELP TO PUT A CIRUS CAP OVER THE DESERTS FROM STORMS THAT DEVELOP
OVER THE MOUNTAINS OF EXTREME SOUTHERN ARIZONA.

BOTTOM LINE FOR TODAY IS FEWER STORMS. STILL EXPECT SOME OF THE
STORMS TO BE STRONG ENOUGH TO DROP IN EXCESS OF AN INCH/HOUR BUT NOT
NEARLY AS MANY OF THEM AS YESTERDAY.

LONGER TERM EXPECT AN INCREASE IN ACTIVITY MORE LIKELY TUESDAY THAN
MONDAY. MONDAY COULD SEE AN INCREASE FROM TODAY BUT TUESDAY MAY BE
EVEN STRONGER AS 4 CORNERS HIGH GETS MORE ESTABLISHED OPENING UP THE
WAY FOR ANOTHER EASTERLY WAVE. BEYOND THAT NO TREND EXCEPT THAT LOW
LEVEL MOISTURE WILL REMAIN. SO SOME DAYS WILL BE MORE ACTIVE THAN
OTHERS BUT SOUTHERN ARIZONA WILL LIKELY SEE THUNDERSTORMS EVERY DAY
THROUGH THIS WEEK.                          PRF

.TWC...NONE.

AZZ019-029>035-260500-
SPECIAL WEATHER STATEMENT...SOUTHEAST ARIZONA CONVECTIVE OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
1120 AM MST SUN JUL 25 1999...THIS PRODUCT IS NOT UPDATED

                          *CONDITIONAL*   *CONDITIONAL*
COUNTY            AREAL    PROBABILITY  RAIN GREATER THAN   STORM
                 COVERAGE   OF SEVERE     1.00      2.00    MOTION

COCHISE             35          20         20        10     NNW12
GRAHAM              35          20         25        10     NNW12
GREENLEE            40          20         30        15     NNW12
TUCSON/ERN PIMA     30          30         25        10     NNW15
TOHONO O'ODHAM      25          35         20        10     N15
SOUTHEAST PINAL     25          35         25        10     N15
WESTERN PIMA        20          40         20        10     N15
SANTA CRUZ          35          20         35        15     NNW12

SYNOPSIS...THE ATMOPSPHERE IS JUST AS MOIST AND EVEN MORE
UNSTABLE THAN YESTERDAY. HOWEVER...LIKE YESTERDAY THERE IS NO
DISTURBANCE TO FOCUS DEVELOPMENT. WIND FIELDS ARE A LITTLE
STRONGER THAN YESTERDAY WHICH REDUCES THE THREAT OF HEAVY RAIN
BUT INCREASES THE CHANCE OF ISOLATED DAMAGING WIND GUSTS. THE
STRONGER WINDS ALOFT SHOULD CAUSE THUNDERSTORM ANVILS TO SPREAD
OUT AND SUPPRESS STORM COVERAGE IN THE VALLEYS SOMEWHAT. THE
STORMS WILL DISSIPATE QUICKLY AFTER SUNSET DUE TO THE LACK OF
ORGANIZATION.

*****************************************************************
KEY...
AREAL COVERAGE - PERCENT OF COUNTY OR AREA THAT WILL EXPERIENCE
                 THUNDERSTORMS
PROB OF SEVERE - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
                 REACH SEVERE LEVELS (DAMAGING WIND AND/OR
                 LARGE HAIL)
RAIN GRTR THAN - THE PROBABILITY THAT AN INDIVIDUAL STORM WILL
                 PRODUCE RAIN EXCEEDING 1 INCH OR 2 INCHES IN
                 ANY LOCATION
STORM MOTION   - GENERAL DIRECTION TO WHICH THE STORMS WILL
                 LIKELY MOVE AND SPEED IN MPH

NOTE...
VALID TIME IS FROM 12:45 PM TO 12 MIDNIGHT OF THE DAY OF ISSUANCE.
THIS PRODUCT IS NOT TO BE USED IN PLACE OF SEVERE THUNDERSTORM OR
FLASH FLOOD WARNINGS OR WATCHES. THIS PRODUCT IS ONLY USED FOR
OUTLOOK PURPOSES. CORRESPONDING GRAPHICS MAY BE FOUND ON THE NWS
TUCSON INTERNET PAGE AT
HTTP://NIMBO.WRH.NOAA.GOV/TUCSON/SWO/SWO.SHTML

END/PYTLAK
CORRECTED TO ADD STORM MOTION