Severe Thunderstorm Warning 88, NWS Tucson, AZ

063 
WWUS55 KTWC 212017
SVSTWC

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
117 PM MST TUE AUG 21 2012

AZC021-212030-
/O.CON.KTWC.SV.W.0088.000000T0000Z-120821T2030Z/
PINAL AZ-
117 PM MST TUE AUG 21 2012

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 130 PM MST
FOR EAST CENTRAL PINAL COUNTY...

AT 107 PM MST...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING DAMAGING WINDS IN
EXCESS OF 60 MPH NEAR MAMMOTH. THIS STORM WAS MOVING SLOWLY TO THE 
EAST AROUND 5 MPH.

LAT...LON 3279 11063 3266 11054 3265 11070 3276 11077
TIME...MOT...LOC 2017Z 267DEG 5KT 3270 11062

$$

144 
WWUS55 KTWC 212026
SVSTWC

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE TUCSON AZ
126 PM MST TUE AUG 21 2012

AZC021-212035-
/O.EXP.KTWC.SV.W.0088.000000T0000Z-120821T2030Z/
PINAL AZ-
126 PM MST TUE AUG 21 2012

...THE SEVERE THUNDERSTORM WARNING FOR EAST CENTRAL PINAL COUNTY WILL
EXPIRE AT 130 PM MST...

DOPPLER RADAR INDICATED THAT THE STORM NEAR MAMMOTH HAS WEAKENED 
CONSIDERABLY AND IS NO LONGER SEVERE. WIND GUSTS TO 35 MPH ALONG 
WITH MODERATE TO LOCALLY HEAVY RAIN WILL CONTINUE THROUGH 145 PM MST.

LAT...LON 3279 11063 3266 11054 3265 11070 3276 11077
TIME...MOT...LOC 2025Z 267DEG 5KT 3270 11061

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE TUCSON AZ
950 AM MST TUE AUG 21 2012

.SYNOPSIS...RAIN CHANCES WILL BE ON THE INCREASE AS A LOW PRESSURE
SYSTEM PASSES THROUGH THE REGION...ESPECIALLY WEDNESDAY INTO
THURSDAY. A DRYING TREND CAN BE EXPECTED BY THE WEEKEND AS DEEPER
MOISTURE MOVES EAST OF THE AREA.

&&

.DISCUSSION...CLEAR TO PARTLY CLOUDY CONDITIONS PREVAILED ACROSS SE
ARIZONA THIS MORNING WITH UPPER HIGH WAS CENTERED OVER NORTHERN
ARIZONA. TIGHT PRECIPITABLE WATER GRADIENT ACROSS THE AREA WITH
VALUES RANGING FROM 1.20" ALONG THE AZ/NM BORDER TO 1.90" IN WRN
PIMA COUNTY. AT THE SURFACE...DEWPOINTS WERE SIMILAR TO WHAT WAS
AROUND 24 HOURS AGO. STARTING OFF THE DAY WITH PLENTY OF SUNSHINE
AND COMBINED WITH A VERY MOIST AND UNSTABLE ATMOSPHERE...WE ARE
LOOKING AT A VERY ACTIVE AFTERNOON/EVENING PERIOD...ESPECIALLY
ACROSS PINAL/SANTA CRUZ AND ERN/CNTRL PIMA COUNTIES. SEE JUST
RELEASED HAZARDOUS WEATHER OUTLOOK FOR MORE DETAILS. WILL LIKELY
MAKE SOME MODIFICATIONS IN THE AFTERNOON PACKAGE AS THE DAY
CONTINUES TO EVOLVE.

REMAINING ACTIVE WEDNESDAY INTO THURSDAY AS A PACIFIC SYSTEM MOVES
INLAND AND INTERACTS WITH THE VERY MOIST ATMOSPHERE. HEAVY RAIN
LEADING TO FLASH FLOODING WILL BE MAIN CONCERN.

&&

.AVIATION...SCT CLOUDS MAINLY ABOVE 12K FT AGL. AFTER 21/19Z...SCT
CLOUDS AT 5-8K FT AGL AND SCT-BKN CLOUDS AT 10-14K FT AGL. SCTD
TSRA/SHRA DEVELOPING MAINLY AFTER 21/20Z AND CONTINUING THRU
22/04Z...WITH MVFR CONDITIONS NEAR THE STRONGER TSRA AND WIND GUSTS
AROUND 40 KNOTS. OTHERWISE...SURFACE WIND MAINLY LESS THAN 10 KTS.
AVIATION DISCUSSION NOT UPDATED FOR TAF AMENDMENTS.

&&

.FIRE WEATHER...EXPECT SCATTERED MAINLY AFTERNOON AND EVENING
THUNDERSTORMS THIS WEEK. STRONG...ERRATIC AND GUSTY WINDS WILL OCCUR
NEAR THUNDERSTORMS. OTHERWISE...EXPECT NORMAL DIURNAL WIND TRENDS
THIS WEEK.

&&

.TWC WATCHES/WARNINGS/ADVISORIES...NONE.

&&

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE TUCSON AZ
941 AM MST TUE AUG 21 2012

AZZ501>515-220600-
WESTERN PIMA COUNTY-TOHONO O'ODHAM NATION-
UPPER SANTA CRUZ RIVER VALLEY/ALTAR VALLEY-TUCSON METRO AREA-
SOUTH CENTRAL PINAL COUNTY-SOUTHEAST PINAL COUNTY-
UPPER SAN PEDRO RIVER VALLEY-
EASTERN COCHISE COUNTY BELOW 5000 FEET-UPPER GILA RIVER VALLEY-
WHITE MOUNTAINS OF GRAHAM AND GREENLEE COUNTIES-
GALIURO AND PINALENO MOUNTAINS-CHIRICAHUA MOUNTAINS-
DRAGOON AND MULE AND HUACHUCA AND SANTA RITA MOUNTAINS-
CATALINA AND RINCON MOUNTAINS-BABOQUIVARI MOUNTAINS-
941 AM MST TUE AUG 21 2012

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
ARIZONA.

.DAY ONE...TODAY AND TONIGHT

A MOIST ATMOSPHERE RESIDING ACROSS SOUTHEAST ARIZONA WILL RESULT IN
SCATTERED COVERAGE OF SHOWERS AND THUNDERSTORMS TODAY...WITH BEST
CHANCES OF PRECIPITATION WEST OF A SAFFORD-TO-BISBEE LINE.

THE MORE FAVORED AREA FOR STRONG THUNDERSTORMS WILL BE ACROSS SOUTH
CENTRAL ARIZONA LATE THIS AFTERNOON AND EARLY THIS EVENING. THIS
WOULD INCLUDE SANTA CRUZ...CENTRAL AND EASTERN PIMA AND SOUTHEAST
PINAL COUNTIES. THE COMBINATION OF A VERY MOIST ATMOSPHERE AND
INCREASINGLY MORE UNSTABLE ATMOSPHERE WILL RESULT IN AN ELEVATED
RISK OF DAMAGING DOWNBURST WINDS AND LOCALIZED FLOODING ISSUES.
A MORE DEFINED THUNDERSTORM OUTFLOW WITH BLOWING DUST TRACKING
NORTHWEST ACROSS CENTRAL/EASTERN PIMA AND SOUTHERN PINAL COUNTIES
WILL BE POSSIBLE LATE THIS AFTERNOON AND EARLY THIS EVENING.

OTHERWISE...A MORE STABLE LAYER ALOFT WILL LIMIT THE OVERALL
INTENSITY OF INDIVIDUAL STORMS EAST OF TUCSON. EXPECT STORMS TO
DEVELOP OVER THE HIGHER TERRAIN LATE THIS MORNING...BUT STRUGGLE TO
MOVE OFF THE MOUNTAINS INTO THE VALLEYS THIS AFTERNOON. ALTHOUGH
THESE STORMS WILL STILL BE ABLE TO PRODUCE LOCALLY HEAVY RAINFALL
AND STRONG GUSTY WINDS...THE RISK OF WIDESPREAD FLOODING ISSUES OR
DAMAGING DOWNBURST WINDS IS RELATIVELY LOW.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

AN INCREASE IN SHOWER AND THUNDERSTORM COVERAGE IS EXPECTED
WEDNESDAY AS MOISTURE CONTINUES TO MOVE INTO THE AREA FROM THE SOUTH.
THIS WILL RESULT IN A RISK OF WIDESPREAD HEAVY RAINFALL.

STRONG THUNDERSTORMS WILL THEN BE POSSIBLE THURSDAY AS A TROUGH OF
LOW PRESSURE TRACKS EASTWARD ACROSS NORTHERN ARIZONA AND INTERACTS
WITH THE VERY MOIST ATMOSPHERE IN PLACE.

A STRONG DECREASE IN THUNDERSTORM ACTIVITY IS EXPECTED FRIDAY...
PERSISTING INTO THE WEEKEND.

.SPOTTER INFORMATION STATEMENT...

WEATHER SPOTTERS ARE ENCOURAGED TO REPORT SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

WEATHER.GOV/TUCSON