Severe Thunderstorm Warning 76, NWS Salt Lake City, UT

000 
WWUS55 KSLC 252301
SVSSLC

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
501 PM MDT FRI AUG 25 2006

UTC023-045-252315-
/O.CON.KSLC.SV.W.0076.000000T0000Z-060825T2315Z/
JUAB UT-TOOELE UT-
501 PM MDT FRI AUG 25 2006

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 515 PM MDT
FOR SOUTHEASTERN TOOELE AND NORTH CENTRAL JUAB COUNTIES...

AT 456 PM MDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A SEVERE THUNDERSTORM CAPABLE OF PRODUCING LARGE DAMAGING
HAIL UP TO GOLF BALL SIZE.  THIS STORM WAS LOCATED OVER NORTH CENTRAL
JUAB COUNTY...OR ABOUT 27 MILES SOUTHEAST OF DUGWAY...MOVING
NORTHEAST AT 40 MPH.

THIS IS A DANGEROUS STORM. IF YOU ARE IN ITS PATH...PREPARE
IMMEDIATELY FOR DAMAGING WINDS...DESTRUCTIVE HAIL...AND DEADLY CLOUD
TO GROUND LIGHTNING. PEOPLE OUTSIDE SHOULD MOVE TO A SHELTER...
PREFERABLY INSIDE A STRONG BUILDING BUT AWAY FROM WINDOWS.

LAT...LON 3984 11307 3966 11294 3982 11235 4005 11250

$$

BAS

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
345 PM MDT FRI AUG 25 2006

.SYNOPSIS...AN UPPER LEVEL LOW WILL SLOWLY MOVE ACROSS NORTHERN UTAH
THROUGH SATURDAY...BRINGING IN NOTICEABLE COOLER AIR. HIGH PRESSURE
WILL BUILD ACROSS THE REGION SUNDAY THROUGH EARLY NEXT WEEK.

&&

.DISCUSSION...LARGE SCALE ASCENT ACROSS THE EASTERN TWO-THIRDS OF
UTAH. POTENT SHORTWAVE AHEAD OF A CLOSED 500MB LOW OVER EASTERN
OREGON IS DIGGING SOUTHEASTWARD. UPPER LEVEL DIVERGENCE AND
INCREASING SHEAR OUT AHEAD OF THE TROUGH WORKING WITH DEEP MOISTURE
TO TRIGGER STRONG TO OCCASIONALLY SEVERE THUNDERSTORMS FROM THE SALT
LAKE AND UTAH VALLEYS EASTWARD TO THE COLORADO BORDER. 12Z SOUNDING
SUPPORTED LARGE HAIL...BUT BUFR SOUNDINGS FOR THIS AFTERNOON
EVEN MORE IMPRESSIVE ACROSS NORTHERN UTAH WHERE THE MOIST AIR IS.
700-300MB SHEAR IN THE 40-50KT RANGE WOULD SUPPORT SOME ROTATING
STORMS AS WELL. EXPECT DYNAMICS TO BE STRONG ENOUGH TO KEEP ACTIVITY
GOING WELL INTO THE NIGHT.

THE TROF EXITS THE STATE BY 12Z SATURDAY...BUT BY THEN COOLING ALOFT
WILL HAVE BEGUN AS THE CLOSED LOW APPROACHES. SLIGHT DIFFERENCES IN
THE NAM/GFS...WITH THE NAM BEING SLIGHTLY DEEPER AND A BIT SLOWER.
GENERALLY AGREEMENT ON A COOLER...UNSTABLE DAY ON SATURDAY. FREEZING
LEVEL LOWERS TO ABOUT 11500FT SAT AFTERNOON AT SLC. COULD SEE A GOOD
AMOUNT OF SMALL HAIL REPORTS WITH AFTERNOON CONVECTION UNDER THE
COLD UPPER LOW.

THE LOW ROTATES THROUGH SAT NIGHT...WITH DRIER NORTHWESTERLY FLOW
DOMINATING SUNDAY. UPPER RIDGING MOVES BODILY OVER THE STATE MONDAY.
STRONG RETURN FLOW ON THE BACKSIDE OF THE RIDGE MOVES IN TUESDAY
WITH THE GUIDANCE SUGGESTING A QUICK WARMUP...BACK TO THE LOW TO MID
90S FOR NORTHERN UTAH VALLEYS.

&&

.FIRE WEATHER...DRY AIR CONTINUES TO MIX DOWN INTO THE SOUTHWEST
VALLEYS AHEAD OF THE COLD FRONT AND WINDS ARE TOUCHING CRITICAL
SPEEDS IN SEVERAL LOCATIONS. EXPECT RH TO CONTINUE FALLING THROUGH
THE REST OF THE AFTERNOON AND IT SHOULD REACH CRITICAL LEVELS OVER
THE FAR SOUTHWEST FOR A TIME BEFORE THE WINDS START TO RELAX. SO
HAVE LEFT RED FLAG WARNING UNCHANGED AND UP TIL 10PM. WETTING RAINS
ARE LIKELY WITH SOME OF THE LARGER STORMS OVER THE NORTH AND EAST
FOR THE REST OF TODAY THROUGH TONIGHT AND ARE POSSIBLE OVER THE
NORTH TOMORROW.

WINDS AND HUMIDITIES COULD LOCALLY REACH CRITICAL LEVELS AGAIN SOUTH
OF THE FRONT SATURDAY ALONG THE ARIZONA BORDER BUT THE REMAINDER OF
THE AREA NORTH OF THE FRONT WILL BE COOLER WITH HIGHER RH.

A STABLE DRY AIRMASS WITH PRIMARILY TERRAIN DRIVEN WINDS WILL BE
OVER THE AREA SUNDAY AS HIGH PRESSURE RETURNS.

&&

.AVIATION...CONVECTION CONTINUES TO DEVELOP OVER NORTHERN UTAH AND A
50 PERCENT CHANCE EXISTS THAT ANOTHER CELL WILL CROSS THE AIRFIELD
THIS EVENING. BEST CHANCE FOR GUSTY WINDS AT THE AIRPORT IS AFTER
SUNSET WHEN CELLS BEGIN TO DISSIPATE PROVIDED THEY REMAIN CLOSE
ENOUGH TO THE AIRFIELD. WINDS AT THE KSLC TERMINAL SHOULD REMAIN
NORTHERLY THROUGH SATURDAY MORNING WHEN A 30 PERCENT CHANCE THAT
SOUTHEAST DRAINAGE WINDS WILL FIGHT AGAINST THE PREDOMINANT
NORTHERLY FLOW BETWEEN 12Z AND 16Z.

&&

.SLC WATCHES/WARNINGS/ADVISORIES...
UT...RED FLAG WARNING UNTIL 10PM MDT FOR FIRE WX ZONES 437 AND 439.
WY...NONE.

&&

SMITH...PUBLIC
WILENSKY...FIRE
YOUNG...AVIATION

HAZARDOUS WEATHER OUTLOOK...UPDATED
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
900 AM MDT FRI AUG 25 2006

UTZ001>012-015-WYZ021-261200-
CACHE VALLEY/UTAH PORTION-CASTLE COUNTRY-
GREAT SALT LAKE DESERT AND MOUNTAINS-NORTHERN WASATCH FRONT-
SALT LAKE AND TOOELE VALLEYS-SOUTHERN WASATCH FRONT-
SOUTHWEST WYOMING-WASATCH MOUNTAIN VALLEYS-WASATCH MOUNTAINS I-
80 NORTH-WASATCH MOUNTAINS SOUTH OF I-80-WASATCH PLATEAU/BOOK CLIFFS-
WEST CENTRAL UTAH-WESTERN UINTA BASIN-WESTERN UINTA MOUNTAINS-
900 AM MDT FRI AUG 25 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHERN AND
WEST CENTRAL UTAH...AND EXTREME SOUTHWEST WYOMING.

.DAY ONE...TODAY AND TONIGHT

AN UPPER TROUGH WILL APPROACH THE REGION TONIGHT AND PUSH
A COLD FRONT ACROSS NORTHERN UTAH. SCATTERED THUNDERSTORMS WILL
DEVELOP AHEAD THIS COLD FRONT. SOME OF THE STORMS MAY CONTAIN HAIL
...GUSTY WINDS AND BRIEF HEAVY RAIN.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

AN UPPER TROUGH WILL SETTLE OVER NORTHERN UTAH ON SATURDAY
AND PRODUCE SCATTERED SHOWERS AND THUNDERSTORMS ALONG WITH
COOLER TEMPERATURES. DRIER WEATHER EXPECTED ON SUNDAY WHEN THE
SYSTEM DEPARTS TO THE EAST.

A SIGNIFICANT WARMING TREND WILL OCCUR EARLY NEXT WEEK WITH AN
INCREASE OF DAILY THUNDERSTORMS BEGINNING TUESDAY.

.SPOTTER INFORMATION STATEMENT...

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

UTZ013-014-016>021-261200-
CENTRAL AND SOUTHWEST MOUNTAINS-
GLEN CANYON RECREATION AREA/LAKE POWELL-HENRY MOUNTAINS-
SAN RAFAEL SWELL-SANPETE/SEVIER VALLEYS-SOUTH CENTRAL UTAH-
SOUTHWEST UTAH-UTAHS DIXIE AND ZION NATIONAL PARK-
900 AM MDT FRI AUG 25 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF CENTRAL UTAH
AND SOUTHERN UTAH.

.DAY ONE...TODAY AND TONIGHT

ISOLATED THUNDERSTORMS WILL OCCUR TODAY AND TONIGHT...MAINLY CENTRAL
AND EASTERN UTAH. BREEZY CONDITIONS AND LOWER HUMIDITY WILL RESULT IN
RED FLAG CONDITIONS FOR FAR SOUTHWEST UTAH TODAY. REFER TO FIRE
WEATHER FORECASTS FOR MORE DETAILS.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH THURSDAY

AN UPPER TROUGH WILL SETTLE OVER NORTHERN UTAH ON SATURDAY. A COLD
FRONT WILL CONTINUE THROUGH SOUTHEAST UTAH DURING SATURDAY
AFTERNOON WITH BREEZY CONDITIONS AHEAD OF THIS. ISOLATED TO SCATTERED
SHOWERS AND THUNDERSTORMS ARE EXPECTED ON SATURDAY...ESPECIALLY
SOUTHEASTERN UTAH.

DRIER WEATHER IS EXPECTED ON SUNDAY WITH THE ONLY SHOWERS LINGERING
IN FAR EASTERN AREAS. A WARMING TREND WILL START MONDAY AND RETURNING
MOISTURE WILL INCREASE DAILY THUNDERSTORMS FOR TUESDAY AND
WEDNESDAY.

.SPOTTER INFORMATION STATEMENT...

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

TARDY

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
315 PM MDT FRI AUG 25 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0150 PM     HAIL             CENTERVILLE             40.93N 111.89W
08/25/2006  E0.50 INCH       DAVIS              UT   NWS EMPLOYEE

            1/2 TO 3/4 INCH HAIL REPORTED NORTH OF CENTERVILLE.

0245 PM     HAIL             PLEASANT GROVE          40.37N 111.73W
08/25/2006  M0.50 INCH       UTAH               UT   TRAINED SPOTTER

            1/2 INCH HAIL REPORTED AT JUNIOR HIGH SCHOOL IN PLEASANT
            GROVE.

0300 PM     HAIL             S CENTERVILLE           40.93N 111.89W
08/25/2006  E1.00 INCH       DAVIS              UT   NEWSPAPER

            NEWSPAPER RELAYED REPORT OF PING-PONG SIZE HAIL FALLING
            SOMEWHERE BETWEEN BOUNTIFUL AND CENTERVILLE IN AN EARLIER
            STORM.

&&

EVC

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
329 PM MDT FRI AUG 25 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0150 PM     HAIL             CENTERVILLE             40.93N 111.89W
08/25/2006  E0.50 INCH       DAVIS              UT   NWS EMPLOYEE

            1/2 TO 3/4 INCH HAIL REPORTED NORTH OF CENTERVILLE.

0245 PM     HAIL             PLEASANT GROVE          40.37N 111.73W
08/25/2006  M0.50 INCH       UTAH               UT   TRAINED SPOTTER

            1/2 INCH HAIL REPORTED AT JUNIOR HIGH SCHOOL IN PLEASANT
            GROVE.

0249 PM     HAIL             HELPER                  39.69N 110.86W
08/25/2006  E1.00 INCH       CARBON             UT   LAW ENFORCEMENT

            QUARTER INCH HAIL.

0300 PM     HAIL             S CENTERVILLE           40.93N 111.89W
08/25/2006  E1.00 INCH       DAVIS              UT   NEWSPAPER

            NEWSPAPER RELAYED REPORT OF PING-PONG SIZE HAIL FALLING
            SOMEWHERE BETWEEN BOUNTIFUL AND CENTERVILLE IN AN EARLIER
            STORM.

&&

EVC

PRELIMINARY LOCAL STORM REPORT...CORRECTED
NATIONAL WEATHER SERVICE SALT LAKE CITY UT
339 PM MDT FRI AUG 25 2006

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0150 PM     HAIL             CENTERVILLE             40.93N 111.89W
08/25/2006  E0.50 INCH       DAVIS              UT   NWS EMPLOYEE

            1/2 TO 3/4 INCH HAIL REPORTED NORTH OF CENTERVILLE.

0245 PM     HAIL             PLEASANT GROVE          40.37N 111.73W
08/25/2006  M0.50 INCH       UTAH               UT   TRAINED SPOTTER

            1/2 INCH HAIL REPORTED AT JUNIOR HIGH SCHOOL IN PLEASANT
            GROVE.

0249 PM     HAIL             HELPER                  39.69N 110.86W
08/25/2006  E1.00 INCH       CARBON             UT   LAW ENFORCEMENT

            QUARTER INCH HAIL.

0300 PM     HAIL             S CENTERVILLE           40.93N 111.89W
08/25/2006  E1.00 INCH       DAVIS              UT   NEWSPAPER

            NEWSPAPER RELAYED REPORT OF PING-PONG SIZE HAIL FALLING
            SOMEWHERE BETWEEN BOUNTIFUL AND CENTERVILLE IN AN EARLIER
            STORM.

0330 PM     HAIL             3 NNE HEBER CITY        40.54N 111.38W
08/25/2006  E1.00 INCH       WASATCH            UT   PUBLIC

            QUARTER SIZE HAIL REPORTED NEAR JORDANELLE RESERVOIR.

&&

EVC