Severe Thunderstorm Warning 25, NWS Las Vegas, NV

000 
WWUS55 KVEF 220826
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
126 AM PDT WED JUL 22 2009

AZC015-CAC071-220845-
/O.CON.KVEF.SV.W.0025.000000T0000Z-090722T0845Z/
MOHAVE AZ-SAN BERNARDINO CA-
126 AM PDT WED JUL 22 2009

...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 145 AM
PDT/145 AM MST/ FOR SOUTHEASTERN SAN BERNARDINO AND SOUTHWESTERN
MOHAVE COUNTIES...

AT 121 AM PDT...NATIONAL WEATHER SERVICE RADAR CONTINUED TO INDICATE 
A SEVERE THUNDERSTORM  LOCATED 12 MILES SOUTHWEST OF TOPOCK...MOVING 
SOUTH AT 20 MPH. AN AUTOMATED WEATHER STATION AT THE NEEDLES AIRPORT 
REPORTED A WIND GUST OF 62 MPH IN ASSOCIATION WITH THIS SAME STORM 
AT 1239 AM. RECENT RADAR TRENDS SUGGEST THIS STORM IS SLIGHTLY 
STRONGER NOW THAN WHEN IT WAS OVER NEEDLES.   

OTHER LOCATIONS IN THE WARNING INCLUDE BUT ARE NOT LIMITED TO DESERT 
HILLS...LAKE HAVASU CITY...VIDAL JUNCTION...EARP AND BIG RIVER.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

THIS STORM HAS A HISTORY OF PRODUCING STRONG WINDS IN EXCESS OF 60 
MPH. SEEK SHELTER NOW INSIDE A STURDY STRUCTURE AND STAY AWAY FROM 
WINDOWS.

&&

LAT...LON 3408 11470 3467 11475 3474 11437 3431 11408
      3431 11412 3427 11411 3418 11423 3413 11434
TIME...MOT...LOC 0822Z 344DEG 17KT 3457 11460

$$

STACHELSKI

000 
WWUS55 KVEF 220841
SVSVEF

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE LAS VEGAS NV
141 AM PDT WED JUL 22 2009

AZC015-CAC071-220848-
/O.EXP.KVEF.SV.W.0025.000000T0000Z-090722T0845Z/
MOHAVE AZ-SAN BERNARDINO CA-
141 AM PDT WED JUL 22 2009

...THE SEVERE THUNDERSTORM WARNING FOR SOUTHEASTERN SAN BERNARDINO
AND SOUTHWESTERN MOHAVE COUNTIES WILL EXPIRE AT 145 AM PDT/145 AM
MST/...

AT 138 AM...NATIONAL WEATHER SERVICE RADAR INDICATED THE 
THUNDERSTORMS OVER SOUTHEASTERN SAN BERNARDINO COUNTY AND 
SOUTHWESTERN MOHAVE COUNTY HAD BEGUN TO WEAKEN TO BELOW SEVERE 
LEVELS. HOWEVER...THIS STORM WILL STILL BE CAPABLE OF PRODUCING WIND 
GUSTS OF 40 TO 50 MPH...ESPECIALLY AS IT APPROACHES VIDAL JUNCTION.  

LAT...LON 3408 11470 3467 11475 3474 11437 3431 11408
      3431 11412 3427 11411 3418 11423 3413 11434
TIME...MOT...LOC 0838Z 344DEG 17KT 3450 11458

$$

STACHELSKI

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE LAS VEGAS NV
840 PM PDT TUE JUL 21 2009

.SYNOPSIS...A MOIST AND UNSTABLE AIRMASS WILL REMAIN OVER THE REGION
THROUGH THE REMAINDER OF THE WEEK. THIS WILL RESULT IN ISOLATED TO
SCATTERED THUNDERSTORMS DEVELOPING DURING THE AFTERNOON AND EVENING
HOURS. TEMPERATURES ARE EXPECTED TO REMAIN NEAR TO SLIGHTLY ABOVE
NORMAL.
&&

.UPDATE...A FEW CELLS HAVE POPPED UP NORTHWEST OF LAS VEGAS AS OF
THIS WRITING ALONG LEADING EDGE OF OUTFLOW BOUNDARY. BOUNDARY IS SET
TO MOVE ACROSS THE REST OF SOUTHERN NYE AND CLARK COUNTIES THIS
EVENING. OUTSIDE OF THIS ACTION...MUCH QUIETER NIGHT THAN LAST
NIGHT. WILL HOLD OFF ON ANY UPDATE UNTIL LATE THIS EVENING AS LOOKS
LIKE CONVECTION WILL DISSIPATE BY LATE EVENING AND WE WILL NOT BE
DEALING WITH ANY STORMS DURING THE LAST NIGHT HOURS.
&&

.AVIATION...FOR MCCARRAN...WINDS WILL SHIFT TO THE NORTH WITH GUSTS
UP TO 25 KTS POSSIBLE AFTER 04Z AS AN OUTFLOW BOUNDARY PUSHES SOUTH
ACROSS LAS VEGAS. AN ISOLATED SHOWER OR THUNDERSTORM WILL PASS
MAINLY TO THE WEST OF LAS VEGAS OVER THE SPRING MOUNTAIN IMPACTING
THE DAGGETT AND BEATTY CORRIDORS THROUGH 05Z. CONVECTION HAS ENDED
IN THE PEACH SPRINGS AND MORMON MESA CORRIDORS. WINDS WILL DECREASE
AFT 06Z BUT REMAIN FROM A NORTH DIRECTION UNDER 10KTS. ISOLATED
THUNDERSTORMS EXPECTED WEDNESDAY MAINLY OVER MOHAVE COUNTY AND THE
HIGHER ELEVATIONS OF SOUTHERN NEVADA WITH OUTFLOW BOUNDARIES MAKING
FOR ERRATIC AND GUSTY WINDS IN THE LATE AFTERNOON OR EVENING HOURS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED THUNDERSTORMS SLOW TO DISSIPATE OVER INYO
COUNTY BUT SHOULD END AROUND 05Z. GENERALLY LIGHT WINDS...BUT MAY
BECOME GUSTY IN THE VICINITY OF STORMS. ISOLATED STORMS EXPECTED
AGAIN WEDNESDAY WITH GENERALLY LIGHT WINDS.
&&

.PREV DISCUSSION...310 PM PDT TUE JUL 21...A COUPLE OF MID LEVEL
CIRCULATIONS NOTICEABLE ON SATELLITE IMAGERY THIS AFTERNOON WITH
ISOLATED THUNDERSTORMS OVER MOHAVE COUNTY. THESE STORMS...HAVE BEEN
MOSTLY PULSE TYPE STORMS AND HAVE NOT PRODUCED MUCH IN THE WAY OF
SIGNIFICANT WEATHER. HOWEVER...SOME STORMS ARE BECOMING MORE
ORGANIZED AND WILL CONTINUE TO MONITOR FOR FURTHER DEVELOPMENT.
GREATER COVERAGE OF THUNDERSTORMS IS LOCATED OVER NORTHERN LINCOLN
COUNTY AND HAVE BEEN SLOWLY DRIFTING SOUTHWARD. THESE STORMS ARE
FORMING THE BEST AREA OF INSTABILITY AND ARE LIKELY TO CONTINUE
DRIFTING SOUTHWARD. ONE THING OF NOTE IS THAT THE AREA BEHIND THE
MID LEVEL CIRCULATION...MAINLY CLARK AND WESTERN MOHAVE
COUNTIES...THE ATMOSPHERE HAS BECOME MUCH MORE STABLE.
HOWEVER...WITH CLOUDS DISSIPATING AND BETTER HEATING EXPECT BETTER
DYNAMICS TO DEVELOP. STILL LOOK FOR THE POTENTIAL OF OUTFLOW FROM
THE LINCOLN COUNTY STORMS TO HELP FIRE CONVECTION THIS EVENING IN
CLARK COUNTY. ON WEDNESDAY...MOISTURE AND INSTABILITY WILL REMAIN IN
PLACE. ALTHOUGH THERE IS NO NOTICEABLE FEATURE TO HELP GENERATE
STORMS...THERE SHOULD BE A FEW ISOLATED STORMS DEVELOPING MAINLY
OVER THE EASTERN AND SOUTHERN HALF OF THE CWA. TEMPERATURES WERE
HELD DOWN TODAY DUE TO PROLONGED CLOUD COVER...BUT WILL RECOVER TO
NEAR NORMAL READINGS TOMORROW.

.LONG TERM...HIGH PRESSURE IS EXPECTED TO REMAIN THE DOMINATE
FEATURE THROUGH THE EXTENDED PERIOD. ONE THING OF NOTE IS THAT THE
GFS IS SHOWING A SLIGHT SHIFT EAST OF THE HIGH CENTER...CLOSER TO
THE 4-CORNERS REGION. THIS MAY LEAD TO A UPSWING IN AVAILABLE
MOISTURE FROM THE SOUTH. THE GFS IS SHOWING THE 2 INCH PW LINE
WORKING INTO SOUTHERN CA FRIDAY MORNING WITH THE 1.5 INCH LINE
WORKING INTO THE SOUTHERN CWA. THIS WOULD LEAD TO BETTER
THUNDERSTORM COVERAGE FRIDAY THROUGH SUNDAY AS MOISTURE HOLDS IN
PLACE. MODELS ARE SHOWING SOME DRYING OCCURRING MONDAY AND TUESDAY
OF NEXT WEEK...BUT WILL TAKE THAT WITH A GRAIN OF SALT THIS TIME OF
YEAR. LITTLE CHANGE WAS NEEDED TO THE EXTENDED.
&&

.VEF WATCHES/WARNINGS/ADVISORIES...
NV...NONE.
AZ...NONE
CA...NONE.
&&

PEIRCE/GORELOW

HTTP://WEATHER.GOV/LASVEGAS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAS VEGAS NV
626 AM PDT TUE JUL 21 2009

AZZ001>003-036-CAZ519>527-NVZ014>022-220700-
NORTHWEST PLATEAU-LOWER COLORADO RIVER VALLEY-NORTHWEST DESERTS-
LAKE MEAD NATIONAL RECREATION AREA-EASTERN SIERRA SLOPES-
OWENS VALLEY-WHITE MOUNTAINS OF INYO COUNTY-
DEATH VALLEY NATIONAL PARK-WESTERN MOJAVE DESERT-
EASTERN MOJAVE DESERT-MORONGO BASIN-CADIZ BASIN-
SAN BERNARDINO COUNTY-UPPER COLORADO RIVER VALLEY-
ESMERALDA AND CENTRAL NYE COUNTY-LINCOLN COUNTY-
NORTHEAST CLARK COUNTY-WESTERN CLARK AND SOUTHERN NYE COUNTY-
SHEEP RANGE-SPRING MOUNTAINS-LAS VEGAS VALLEY-
SOUTHERN CLARK COUNTY-
626 AM PDT TUE JUL 21 2009 /626 AM MST TUE JUL 21 2009/

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF NORTHWEST
ARIZONA...SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA.

.DAY ONE...TODAY AND TONIGHT

THUNDERSTORMS ARE EXPECTED TO INITIALLY DEVELOP OVER THE MOUNTAINS
THIS AFTERNOON THEN MOVE FROM NORTH TO SOUTH INTO THE VALLEYS AND
DESERTS LATE THIS AFTERNOON AND EVENING. THE MAIN HAZARDS WILL BE
HIGH WINDS...HEAVY RAIN AND HAIL WITH THE STRONGEST STORMS.
CENTRAL AND EASTERN CLARK COUNTY...INCLUDING LAS VEGAS AND THE
LAKE MEAD NATIONAL RECREATION AREA...COULD BE FAVORED FOR THESE
HAZARDS THIS EVENING.

.DAYS TWO THROUGH SEVEN...WEDNESDAY THROUGH MONDAY

MOIST AND UNSTABLE AIR WILL REMAIN OVER THE REGION THROUGH THE
WEEKEND FOR A THREAT OF THUNDERSTORMS EACH DAY...MAINLY IN THE
AFTERNOON AND EVENING HOURS. A POSSIBLE MOISTURE INCREASE FRIDAY
WILL LEAD TO A BETTER CHANCE OF LOCALIZED HEAVY RAIN AND POSSIBLE
FLASH FLOODING WITH SOME STORMS.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED BUT THERE IS A SLIGHT
POSSIBILITY THAT INFORMAL ACTIVATION MAY BE NEEDED AS THUNDERSTORM
COVERAGE INCREASES THIS AFTERNOON AND EVENING. SPOTTERS ARE
ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER ACCORDING TO STANDARD
OPERATING PROCEDURES.

JA