Flash Flood Watch 5, NWS Las Vegas, NV

751 
WGUS65 KVEF 150157
FFAVEF

FLOOD WATCH
NATIONAL WEATHER SERVICE LAS VEGAS NV
657 PM PDT WED SEP 14 2011

...FLASH FLOODING IS POSSIBLE IN FAR SOUTHERN NEVADA AND
NORTHWEST ARIZONA THROUGH 10 PM TONIGHT...

AZZ001-003-036-NVZ016>022-150500-
/O.CON.KVEF.FF.A.0005.000000T0000Z-110915T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NORTHWEST PLATEAU-NORTHWEST DESERTS-
LAKE MEAD NATIONAL RECREATION AREA-NORTHEAST CLARK COUNTY-
WESTERN CLARK AND SOUTHERN NYE COUNTY-SHEEP RANGE-
SPRING MOUNTAINS-RED ROCK CANYON-LAS VEGAS VALLEY-
SOUTHERN CLARK COUNTY-
657 PM PDT WED SEP 14 2011 /657 PM MST WED SEP 14 2011/

...FLASH FLOOD WATCH REMAINS IN EFFECT UNTIL 10 PM PDT /10 PM
MST/ THIS EVENING...

THE FLASH FLOOD WATCH CONTINUES FOR

* PORTIONS OF NORTHWEST ARIZONA AND SOUTHERN NEVADA...INCLUDING 
  THE FOLLOWING AREAS...IN NORTHWEST ARIZONA...LAKE MEAD 
  NATIONAL RECREATION AREA...NORTHWEST DESERTS AND NORTHWEST 
  PLATEAU. IN SOUTHERN NEVADA...LAKE MEAD NATIONAL RECREATION 
  AREA...LAS VEGAS VALLEY...NORTHEAST CLARK COUNTY...SHEEP 
  RANGE...SOUTHERN CLARK COUNTY...SPRING MOUNTAINS-RED ROCK 
  CANYON AND WESTERN CLARK AND SOUTHERN NYE COUNTY. 

* UNTIL 10 PM PDT /10 PM MST/ THIS EVENING

* SCATTERED THUNDERSTORMS WILL SLOWLY DECREASE THROUGH THE
  EVENING HOURS...HOWEVER CONDITIONS REMAIN FAVORABLE FOR PERIODS
  OF BRIEF HEAVY RAINFALL FROM THESE STORMS THROUGH THIS EVENING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A FLASH FLOOD WATCH MEANS THAT CONDITIONS MAY DEVELOP THAT LEAD
TO FLASH FLOODING. FLASH FLOODING IS A VERY DANGEROUS SITUATION
AND PERSONS IN AND NEAR THE WATCH AREA SHOULD BE ALERT TO THE
POTENTIAL FOR HEAVY RAINFALL.

&&

$$

JENSEN

765 
WGUS65 KVEF 150321
FFAVEF

FLOOD WATCH
NATIONAL WEATHER SERVICE LAS VEGAS NV
821 PM PDT WED SEP 14 2011


AZZ001-003-036-NVZ016>022-150430-
/O.CAN.KVEF.FF.A.0005.000000T0000Z-110915T0500Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NORTHWEST PLATEAU-NORTHWEST DESERTS-
LAKE MEAD NATIONAL RECREATION AREA-NORTHEAST CLARK COUNTY-
WESTERN CLARK AND SOUTHERN NYE COUNTY-SHEEP RANGE-
SPRING MOUNTAINS-RED ROCK CANYON-LAS VEGAS VALLEY-
SOUTHERN CLARK COUNTY-
821 PM PDT WED SEP 14 2011 /821 PM MST WED SEP 14 2011/

...FLASH FLOOD WATCH IS CANCELLED...

THE FLASH FLOOD WATCH FOR PORTIONS OF NORTHWEST ARIZONA AND
SOUTHERN NEVADA HAS BEEN CANCELLED. 

THUNDERSTORMS HAVE DECREASED ACROSS THE AREA EARLY THIS EVENING
AND ALTHOUGH SCATTERED SHOWERS WILL BE SEEN INTO MIDNIGHT...HEAVY
RAINFALL WHICH MAY PRODUCE FLASH FLOODING IS NO LONGER EXPECTED.
THUS THE FLASH FLOOD WATCH HAS BEEN CANCELLED.

$$

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
947 AM PDT WED SEP 14 2011

.SYNOPSIS...AN AREA OF LOW PRESSURE WILL SLOWLY MOVE ACROSS NORTHERN
ARIZONA TODAY AND THURSDAY LEADING TO A CONTINUED CHANCE OF RAIN
SHOWERS AND THUNDERSTORMS...WITH SOME RAIN SHOWERS PERSISTING
OVERNIGHT. A DRIER SOUTHWEST FLOW WILL DEVELOP OVER THE REGION GOING
INTO THE WEEKEND WITH TEMPERATURES REMAINING A LITTLE BELOW NORMAL.
TEMPERATURES WILL WARM BACK ABOVE NORMAL EARLY NEXT WEEK AS HIGH
PRESSURE BUILDS OVER THE REGION.
&&

.UPDATE...VEF SOUNDING AND PROJECTED AREA SOUNDINGS SHOW
CONSIDERABLE MOISTURE AND INSTABILITY OVER SOUTHERN NEVADA AND
NORTHWEST ARIZONA TODAY. MAIN CONCERN IS THE POTENTIAL FOR HEAVY
RAINFALL AND POSSIBLE FLOODING ISSUES ASSOCIATED WITH ANY
THUNDERSTORMS THAT OCCUR TODAY. EXPECT THE MAIN THREAT AREA TO BE
NORTHERN MOHAVE COUNTY WHERE THERE IS CURRENTLY LITTLE CLOUD COVER
AND WHERE THE LOW IS CURRENTLY SITTING. WILL NEED TO LOOK CLOSER AT
THE AREA AND MAY UPDATE LATER.
&&

.PREV DISCUSSION...
439 AM PDT WED SEP 14 2011

.SHORT TERM...TODAY THROUGH FRIDAY EVENING...UPPER LOW SETTING JUST
SOUTHEAST OF LAS VEGAS EARLY THIS MORNING. REGIONAL RADAR SHOWS AN
AREA OF SHOWERS OVER NORTHERN MOHAVE COUNTY...THEN WRAPPING BACK
AROUND THE LOW ACROSS LINCOLN...WESTERN CLARK AND SOUTHERN NYE
COUNTIES. SINCE MIDNIGHT...SEVERAL CLARK COUNTY ALERT GAGES IN
SOUTHEAST LAS VEGAS VALLEY HAVE REPORTED BETWEEN THREE AND FOUR
TENTHS ON AN INCH. MOST STATIONS THOUGH HAVE PREDOMINATELY SHOWN
AMOUNTS LESS THAN A TWO TENTHS OF INCH.

WRAP AROUND MOISTURE WILL CONTINUE ACROSS LINCOLN...CLARK...NYE...
MOHAVE AND NORTHEAST SAN BERNARDINO COUNTY THROUGHOUT THE DAY AS THE
UPPER LOW VERY SLOWLY MOVES EASTWARD OVER NORTHERN MOHAVE COUNTY BY
LATE THIS AFTERNOON. LIGHTNING DETECTION NETWORK HAS NOT SHOWN AN
STRIKES SINCE ABOUT 1 AM. DID INCREASE THE POPS AND EMPHASIZED RAIN
SHOWERS THIS MORNING BEFORE AIR MASS BECOMES SLIGHTLY MORE UNSTABLE
THIS AFTERNOON TO SUPPORT STRONGER CONVECTION. CLOUDS/PRECIPITATION
WILL AGAIN KEEP TEMPERATURES WELL BELOW NORMAL TODAY.

UPPER LOW WILL FINALLY BEGIN TO ACCELERATE EAST ON THURSDAY AS A
STRONGER UPSTREAM TROUGH APPROACHES THE PACIFIC NORTHWEST COAST.
MOISTURE WILL REMAIN PLENTIFUL ALONG WITH JUST ENOUGH INSTABILITY
ESPECIALLY ACROSS THE EASTERN HALF OF THE AREA FOR A CHANCE OF
THUNDERSTORMS MOSTLY AROUND THE HIGHER TERRAIN. ON FRIDAY...TROUGH
PROGRESSES INLAND INTO THE GREAT BASIN WITH GFS A TAD DEEPER THAN
THE NAM. TROUGH WILL HAVE SOME MOISTURE TO WORK WITH AS DRIER
SOUTHWEST FLOW WILL NOT HAVE YET SCOURED MOISTURE OUT OF EASTERN
NEVADA AND NORTHWEST ARIZONA. WARMER TEMPERATURES ON THURSDAY AND
FRIDAY.

.LONG TERM...WE CONTINUE TO FOLLOW A BLEND OF THE OPERATIONAL RUNS
OF THE ECMWF AND GFS AND GFS ENSEMBLES FOR THE PERIOD FROM THIS
WEEKEND INTO THE MIDDLE OF NEXT WEEK. THE LATEST RUNS OF EACH PUSH A
MID AND UPPER LEVEL TROUGH AXIS EAST OF THE AREA FOR SATURDAY AND
THUS GIVEN THE MODELS SHOW A DRY NORTHWEST FLOW ALOFT OVERHEAD WE
KEPT THE FORECAST FREE OF ANY PRECIPITATION. ON SUNDAY A FLAT RIDGE
IN THE MID AND UPPER LEVELS BEGINS TO SLIDE EAST INTO THE SW U.S.
AND THIS SHOULD RESULT IN ANOTHER DRY DAY WITH FURTHER HEIGHT RISES.
TEMPS SHOULD GRADUALLY WARM THIS WEEKEND WITH HIGHS A LITTLE BELOW
NORMAL.

A SYSTEM MOVING ACROSS THE PAC NW ON SUNDAY IS SHOWN TO DIG DEEPER
ON THE ECMWF ON MONDAY AS IT MOVES OVER THE ROCKIES THAN IT DOES ON
THE GFS AND ON MOST OF THE GFS ENSEMBLES. THE GEM MODEL WAS SHOWING
THIS LAST NIGHT AND HAD A FUNKY SOLUTION WHERE IT EVENTUALLY CLOSED
OFF A BIG LOW BUT IT NOW HAS TRENDED TOWARDS THE ECMWF IN SHOWING AN
OPEN WAVE SWIPING NORTHEAST NEVADA LATE MONDAY. FOR US...THE ONLY
IMPACT A DEEPER TROUGH WOULD HAVE WOULD BE A LITTLE WIND AND A
SLOWER WARMING TREND ON MONDAY BUT ANY WAY YOU LOOK AT THINGS IT
STAYS DRY. AFTERWARDS ALL THE MODELS AGREE ON A RIDGE IN THE MID AND
UPPER LEVELS BUILDING INTO CALIFORNIA AND NEVADA BY THE MIDDLE
PORTION OF NEXT WEEK. THIS WILL KEEP THINGS DRY AND RELATIVELY SUNNY
AND WITH 500 MB HEIGHTS PROGGED TO BE 587-590 DM...ALLOW HIGH TEMPS
TO SOAR ABOVE NORMAL. WE MAY GET ANOTHER SHOT AT TRIPLE DIGITS IN
LAS VEGAS BY NEXT THURSDAY OR FRIDAY BUT FOR NOW I HAVE OPTED TO
KEEP TEMPS JUST BELOW THAT.
&&

.AVIATION...FOR MCCARRAN...WITH THE UPPER LOW STILL AROUND TODAY
SHRA AND TSRA WILL BE POSSIBLE AT TIMES THROUGH THIS EVENING IN AND
AROUND THE LAS VEGAS VALLEY AND IN THE APPROACH CORRIDORS. TIMING ON
ACTIVITY IS UNCERTAIN AND THUS WILL KEEP THE TAF BROADBRUSHED WITH
VCTY ACTIVITY FOR NOW AND REFINE TIMING WITH AMENDMENTS AND
SUBSEQUENT TAF PACKAGES. CONFIDENCE WILL BE HIGHEST IN ACTIVITY IN
THE EARLIEST PART OF THE TAF WITH REDUCED CONFIDENCE FOR LATER
PERIODS. MAINLY BKN CIGS AOA 8K-14K FEET WITH BASES LOWERING TO
AROUND 6K FEET NEAR SHRA/TSRA. GUSTY AND ERRATIC WINDS WILL ALSO BE
A HAZARD IN AND NEAR SHRA/TSRA. OTHERWISE WINDS WILL TREND TOWARDS
TYPICAL DIURNAL SHIFTS THROUGH TONIGHT AT SPEEDS OF 10 KTS OR LESS.
SHRA/TSRA SHOULD DIMINISH IN COVERAGE AFTER 04Z THURSDAY WITH
SCT-BKN CLOUDS AOA 10K FEET.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SCT SHRA/TSRA THROUGH THIS EVENING ESPECIALLY ACROSS
MOHAVE...CLARK...LINCOLN...SOUTHERN NYE...SOUTHEAST INYO AND EASTERN
SAN BERNARDINO COUNTIES. SHRA/TSRA ACTIVITY SHOULD DIMINISH AROUND
04Z THURSDAY. THE MAIN THREATS IN AND NEAR SHRA/TSRA WILL BE GUSTY
AND ERRATIC WINDS AND REDUCED CIGS AND VSBY. OTHERWISE EXPECT WINDS
TO FAVOR TYPICAL DIURNAL DIRECTIONS AND SPEEDS. BKN-OVC AOA 8K-14K
FEET THROUGH THIS EVENING WITH SCT-BKN CLOUDS AOA 10K FEET TONIGHT.
&&

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

JACQUES/PIERCE/STACHELSKI

HTTP://WEATHER.GOV/LASVEGAS

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAS VEGAS NV
456 AM PDT WED SEP 14 2011

AZZ001>003-036-CAZ522-524>527-NVZ015>022-150700-
NORTHWEST PLATEAU-LOWER COLORADO RIVER VALLEY-NORTHWEST DESERTS-
LAKE MEAD NATIONAL RECREATION AREA-DEATH VALLEY NATIONAL PARK-
EASTERN MOJAVE DESERT-MORONGO BASIN-CADIZ BASIN-
SAN BERNARDINO COUNTY-UPPER COLORADO RIVER VALLEY-LINCOLN COUNTY-
NORTHEAST CLARK COUNTY-WESTERN CLARK AND SOUTHERN NYE COUNTY-
SHEEP RANGE-SPRING MOUNTAINS-LAS VEGAS VALLEY-
SOUTHERN CLARK COUNTY-
456 AM PDT WED SEP 14 2011 /456 AM MST WED SEP 14 2011/

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

.DAY ONE...TODAY AND TONIGHT

RAIN SHOWERS WITH ISOLATED EMBEDDED THUNDERSTORMS CIRCULATING
AROUND AN AREA OF LOW PRESSURE OVER NORTHWEST ARIZONA WITH GIVE
WAY TO ISOLATED TO SCATTERED THUNDERSTORMS THIS AFTERNOON AND
EVENING.

BRIEF BURSTS OF HEAVY RAIN COULD LEAD TO PONDING OF WATER IN LOW
LYING AREAS AND ON ROADWAYS...WITH SOME FLOWING WATER IN NORMALLY DRY
WASHES.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

A CHANCE OF SHOWERS AND THUNDERSTORMS WILL CONTINUE THROUGH FRIDAY
MOSTLY ACROSS EAST CENTRAL NEVADA AND NORTHWEST ARIZONA. NO
HAZARDOUS WEATHER IS EXPECTED AT THIS TIME SATURDAY THROUGH
TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. HOWEVER...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

CAZ519>521-523-NVZ014-150700-
EASTERN SIERRA SLOPES-OWENS VALLEY-WHITE MOUNTAINS OF INYO COUNTY-
WESTERN MOJAVE DESERT-ESMERALDA AND CENTRAL NYE COUNTY-
456 AM PDT WED SEP 14 2011

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

.DAY ONE...TODAY AND TONIGHT

ISOLATED SHOWERS AND THUNDERSTORMS WILL OCCUR TODAY AS AN AREA OF
LOW PRESSURE SLOWLY MOVES ACROSS NORTHWEST ARIZONA.

BRIEF BURSTS OF MODERATE RAIN COULD LEAD TO PONDING OF WATER IN LOW
LYING AREAS AND ON ROADWAYS...WITH SOME FLOWING WATER IN NORMALLY DRY
WASHES.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

THERE WILL REMAIN A SLIGHT CHANCE OF SHOWERS AND THUNDERSTORMS
ACROSS NORTHERN INYO AND ESMERALDA COUNTIES THROUGH FRIDAY.
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME SATURDAY THROUGH
TUESDAY.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS NOT EXPECTED AT THIS TIME. HOWEVER...
SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT WEATHER
CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.

PIERCE