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000
FXUS65 KVEF 302218
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
318 PM PDT WED JUL 30 2014

.SYNOPSIS...SHOWERS AND THUNDERSTORMS OVER THE SOUTHERN SIERRA AND
WEST CENTRAL NEVADA WILL DIMINISH LATE THIS EVENING. THUNDERSTORM
DEVELOPMENT WILL BE MORE ISOLATED OVER THE SOUTHERN SIERRA AND
SOUTHERN GREAT BASIN UNDER A DRIER AND MORE STABLE WESTERLY FLOW
THURSDAY AND FRIDAY. ANOTHER PUSH OF MOISTURE IS EXPECTED TO
SPREAD UP ACROSS THE REGION OVER THE WEEKEND FOR AN UPSWING IN
SHOWERS AND THUNDERSTORMS.
&&

.SHORT TERM...THROUGH FRIDAY NIGHT...SHOWERS AND EMBEDDED
THUNDERSTORMS HAVE BEEN EXPANDING ACROSS MUCH OF THE SOUTHERN SIERRA
AND NORTHERN INYO COUNTY THIS AFTERNOON AND WILL PERSIST INTO THE
EVENING AS REMNANT MOISTURE FROM FORMER TROPICAL SYSTEM HERNAN IS
PULLED ACROSS THE SOUTHERN SIERRA. PRECIPITATION WILL THEN TAPER OFF
LATE THIS EVENING AND OVERNIGHT. ELSEWHERE...ISOLATED THUNDERSTORMS
WERE DEVELOPING OVER THE MOUNTAINS OF SOUTHERN NEVADA AND NORTHWEST
ARIZONA. PRECIPITATION HAS BEEN GENERALLY LIGHT WITH THESE CELLS.
DRIER AIR WILL SPREAD OVER INYO COUNTY LATE TONIGHT AND THURSDAY AND
THE REST OF THE REGION WILL SEE A SLIGHT DECREASE IN MOISTURE WITH
MODERATELY UNSTABLE CONDITIONS PERSISTING OVER THE SAME AREA AS
TODAY. THIS WILL KEEP A SLIGHT CHANCE OF THUNDERSTORMS OVER ZONES
FROM THE MOUNTAINS OF SOUTHERN NEVADA AND NORTHWEST ARIZONA
NORTHWARD. A LITTLE DRIER AND MORE STABLE AIR WILL SPREAD OVER THE
REGION FRIDAY LEAVING ONLY A SLIGHT CHANCE OF THUNDERSTORMS OVER THE
SOUTHERN SIERRA...SOUTH CENTRAL NEVADA AND NORTHWEST ARIZONA. THIS
RELATIVELY DRY PATTERN WILL BREAK AFTER FRIDAY AND THE 12Z MODELS
SUPPORT THE TRENDS DETAILED IN THE LONG TERM DISCUSSION. NO
SIGNIFICANT CHANGES WERE MADE TO THE FORECAST BEYOND FRIDAY.
&&

.LONG TERM...SATURDAY THROUGH WEDNESDAY.

WELL GET READY FOR ANOTHER PUSH OF JUICIER MOISTURE THIS WEEKEND,
ESPECIALLY OVER THE EASTERN HALF OF THE AREA, AS THE FLOW ALOFT
TRANSITIONS TO THE SOUTHEAST BY SATURDAY MORNING ACROSS OUR AREA AS
THE CLASSIC SUMMERTIME FOUR CORNERS HIGH SETS BACK UP. AT LEAST
INITIALLY, IT APPEARS THAT WHATEVER SHOWER AND THUNDERSTORM ACTIVITY
THAT DEVELOPS ON SATURDAY AFTERNOON AND EVENING SHOULD DEVELOP
COURTESY OF ANY DIFFERENTIAL HEATING BOUNDARIES OR BE TERRAIN
INDUCED. THE LATEST ECMWF AND GFS ARE MORE STABLE OVER THE WESTERN
CWFA AND THUS IF THIS TREND CONTINUES WE MAY NEED TO TRIM POPS THERE
DOWN. PWAT VALUES PUSHING 1.50 INCHES WILL MEAN THE ATMOSPHERE WILL
HAVE A LOT OF JUICE AND THUS FLASH FLOODING WILL BE THE PRIMARY
THREAT IN STRONGER OR SLOWER MOVING STORMS.

THINGS GET MORE INTERESTING SATURDAY NIGHT THROUGH MONDAY AS AN
INVERTED TROUGH OR SOME SORT OF VORTICITY MAXIMUM OR LOBE HEADS
NORTHWEST FROM CENTRAL ARIZONA AND CROSSES THE AREA. THIS FEATURE
SHOULD LIFT SLOWLY NORTHEAST ON MONDAY BUT CONTINUES TO TREND TOWARD
A SLOWER EXIT ON THE MODELS. THE PRESENCE OF THIS FEATURE IS SHOWN
ON THE BIG 4 MEDIUM RANGE OPERATIONAL MODELS (GFS, ECMWF, GEM AND
DGEX) AND THIS TRIGGER FEATURE COMBINED WITH THE HIGH MOISTURE
CONTENT AVAILABLE SHOULD RESULT IN AN EVEN BETTER CHANCE FOR SHOWERS
AND THUNDERSTORMS EVEN AT NIGHT. POPS WERE RAISED AGAIN TO SHOW A
BETTER UPTICK IN ACTIVITY FOR SUNDAY THROUGH MONDAY. THE MAIN
CONCERN CONTINUES TO BE HOW MUCH CLOUD COVER EXISTS AS THIS WOULD
LIMIT HEATING AND RESULT IN MORE SHOWERS AND LOW-GRADE
THUNDERSTORMS. HOWEVER, IF WE GET ENOUGH HEATING SUNDAY, ACTIVITY
WOULD SUPPORT THE POTENTIAL FOR STRONGER THUNDERSTORMS WITH 0-6 KM
BULK SHEAR VALUES SHOWN BY THE GFS TO EXCEED 20 KTS ACROSS THE
EASTERN CWFA. HEAVY RAIN PRODUCING THUNDERSTORMS WILL BE THE MAIN
THREAT ALONG WITH THE RISK FOR FLASH FLOODING. HIGH TEMPS WILL BE
VERY TRICKY ESPECIALLY ON SUNDAY AS CLOUDS COULD EASILY HOLD TEMPS
DOWN ANOTHER 6-8 DEGREES FROM WHAT IS FORECAST.

THE LATEST MODELS NOW SHOW A SLOWER EXIT TO THIS FEATURE KEEPING IT
OVER THE NORTHEAST CWFA THROUGH TUESDAY BEFORE FINALLY GIVING IT THE
BOOT. THUS POPS WERE RAISED MONDAY THROUGH TUESDAY ESPECIALLY IN
LINCOLN COUNTY. DRIER AIR SHOULD FINALLY WORK IN FROM THE SOUTHWEST
AS THE FLOW ALOFT TURNS IN THAT DIRECTION AND THIS SHOULD CUT BACK
ON THE COVERAGE OF STORMS OUT THAT WAY. WITH LESS CLOUDS, TEMPS
SHOULD TREND BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...SHOWERS NEAR THE SPRING MOUNTAINS WILL
DIMINISH DURING THE LATE AFTERNOON AND EVENING. WINDS WILL DECREASE
TO AROUND 10 KTS FROM THE WEST-SOUTHWEST THROUGH LATE EVENING THEN
BECOME LIGHT DIURNAL PATTERNS EARLY THURSDAY MORNING. SCATTERED
SHOWERS AND THUNDERSTORMS WILL PERSIST IN THE BEATTY CORRIDOR
THROUGH LATE EVENING. ISOLATED THUNDERSTORMS WILL BE POSSIBLE
THURSDAY AFTERNOON AND EVENING OVER THE SPRING MOUNTAINS AND THE
BEATTY/MORMON MESA CORRIDORS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SCATTERED SHOWERS AND THUNDERSTORMS OVER NORTHERN
INYO...ESMERALDA AND CENTRAL NYE COUNTIES WILL PERSIST THROUGH THIS
EVENING THEN DIMINISH OVERNIGHT. WIND GUSTS OF 25-35 KTS WILL OCCUR
NEAR STORMS. SCT-BKN BASES AROUND 10 KFT MSL CAN BE EXPECTED WITH
MOUNTAIN TOP OBSCUREMENT. ISOLATED THUNDERSTORMS ELSEWHERE ACROSS
THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA WILL DISSIPATE EARLY
THIS EVENING. CONSIDERABLY LESS THUNDERSTORM COVERAGE IS EXPECTED
THURSDAY WITH ISOLATED STORMS CONFINED TO THE HIGHER MOUNTAINS AND
ONLY SCT BASES AROUND 12-15KFT MSL.
&&

.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.
&&

SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER







000
FXUS65 KVEF 302218
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
318 PM PDT WED JUL 30 2014

.SYNOPSIS...SHOWERS AND THUNDERSTORMS OVER THE SOUTHERN SIERRA AND
WEST CENTRAL NEVADA WILL DIMINISH LATE THIS EVENING. THUNDERSTORM
DEVELOPMENT WILL BE MORE ISOLATED OVER THE SOUTHERN SIERRA AND
SOUTHERN GREAT BASIN UNDER A DRIER AND MORE STABLE WESTERLY FLOW
THURSDAY AND FRIDAY. ANOTHER PUSH OF MOISTURE IS EXPECTED TO
SPREAD UP ACROSS THE REGION OVER THE WEEKEND FOR AN UPSWING IN
SHOWERS AND THUNDERSTORMS.
&&

.SHORT TERM...THROUGH FRIDAY NIGHT...SHOWERS AND EMBEDDED
THUNDERSTORMS HAVE BEEN EXPANDING ACROSS MUCH OF THE SOUTHERN SIERRA
AND NORTHERN INYO COUNTY THIS AFTERNOON AND WILL PERSIST INTO THE
EVENING AS REMNANT MOISTURE FROM FORMER TROPICAL SYSTEM HERNAN IS
PULLED ACROSS THE SOUTHERN SIERRA. PRECIPITATION WILL THEN TAPER OFF
LATE THIS EVENING AND OVERNIGHT. ELSEWHERE...ISOLATED THUNDERSTORMS
WERE DEVELOPING OVER THE MOUNTAINS OF SOUTHERN NEVADA AND NORTHWEST
ARIZONA. PRECIPITATION HAS BEEN GENERALLY LIGHT WITH THESE CELLS.
DRIER AIR WILL SPREAD OVER INYO COUNTY LATE TONIGHT AND THURSDAY AND
THE REST OF THE REGION WILL SEE A SLIGHT DECREASE IN MOISTURE WITH
MODERATELY UNSTABLE CONDITIONS PERSISTING OVER THE SAME AREA AS
TODAY. THIS WILL KEEP A SLIGHT CHANCE OF THUNDERSTORMS OVER ZONES
FROM THE MOUNTAINS OF SOUTHERN NEVADA AND NORTHWEST ARIZONA
NORTHWARD. A LITTLE DRIER AND MORE STABLE AIR WILL SPREAD OVER THE
REGION FRIDAY LEAVING ONLY A SLIGHT CHANCE OF THUNDERSTORMS OVER THE
SOUTHERN SIERRA...SOUTH CENTRAL NEVADA AND NORTHWEST ARIZONA. THIS
RELATIVELY DRY PATTERN WILL BREAK AFTER FRIDAY AND THE 12Z MODELS
SUPPORT THE TRENDS DETAILED IN THE LONG TERM DISCUSSION. NO
SIGNIFICANT CHANGES WERE MADE TO THE FORECAST BEYOND FRIDAY.
&&

.LONG TERM...SATURDAY THROUGH WEDNESDAY.

WELL GET READY FOR ANOTHER PUSH OF JUICIER MOISTURE THIS WEEKEND,
ESPECIALLY OVER THE EASTERN HALF OF THE AREA, AS THE FLOW ALOFT
TRANSITIONS TO THE SOUTHEAST BY SATURDAY MORNING ACROSS OUR AREA AS
THE CLASSIC SUMMERTIME FOUR CORNERS HIGH SETS BACK UP. AT LEAST
INITIALLY, IT APPEARS THAT WHATEVER SHOWER AND THUNDERSTORM ACTIVITY
THAT DEVELOPS ON SATURDAY AFTERNOON AND EVENING SHOULD DEVELOP
COURTESY OF ANY DIFFERENTIAL HEATING BOUNDARIES OR BE TERRAIN
INDUCED. THE LATEST ECMWF AND GFS ARE MORE STABLE OVER THE WESTERN
CWFA AND THUS IF THIS TREND CONTINUES WE MAY NEED TO TRIM POPS THERE
DOWN. PWAT VALUES PUSHING 1.50 INCHES WILL MEAN THE ATMOSPHERE WILL
HAVE A LOT OF JUICE AND THUS FLASH FLOODING WILL BE THE PRIMARY
THREAT IN STRONGER OR SLOWER MOVING STORMS.

THINGS GET MORE INTERESTING SATURDAY NIGHT THROUGH MONDAY AS AN
INVERTED TROUGH OR SOME SORT OF VORTICITY MAXIMUM OR LOBE HEADS
NORTHWEST FROM CENTRAL ARIZONA AND CROSSES THE AREA. THIS FEATURE
SHOULD LIFT SLOWLY NORTHEAST ON MONDAY BUT CONTINUES TO TREND TOWARD
A SLOWER EXIT ON THE MODELS. THE PRESENCE OF THIS FEATURE IS SHOWN
ON THE BIG 4 MEDIUM RANGE OPERATIONAL MODELS (GFS, ECMWF, GEM AND
DGEX) AND THIS TRIGGER FEATURE COMBINED WITH THE HIGH MOISTURE
CONTENT AVAILABLE SHOULD RESULT IN AN EVEN BETTER CHANCE FOR SHOWERS
AND THUNDERSTORMS EVEN AT NIGHT. POPS WERE RAISED AGAIN TO SHOW A
BETTER UPTICK IN ACTIVITY FOR SUNDAY THROUGH MONDAY. THE MAIN
CONCERN CONTINUES TO BE HOW MUCH CLOUD COVER EXISTS AS THIS WOULD
LIMIT HEATING AND RESULT IN MORE SHOWERS AND LOW-GRADE
THUNDERSTORMS. HOWEVER, IF WE GET ENOUGH HEATING SUNDAY, ACTIVITY
WOULD SUPPORT THE POTENTIAL FOR STRONGER THUNDERSTORMS WITH 0-6 KM
BULK SHEAR VALUES SHOWN BY THE GFS TO EXCEED 20 KTS ACROSS THE
EASTERN CWFA. HEAVY RAIN PRODUCING THUNDERSTORMS WILL BE THE MAIN
THREAT ALONG WITH THE RISK FOR FLASH FLOODING. HIGH TEMPS WILL BE
VERY TRICKY ESPECIALLY ON SUNDAY AS CLOUDS COULD EASILY HOLD TEMPS
DOWN ANOTHER 6-8 DEGREES FROM WHAT IS FORECAST.

THE LATEST MODELS NOW SHOW A SLOWER EXIT TO THIS FEATURE KEEPING IT
OVER THE NORTHEAST CWFA THROUGH TUESDAY BEFORE FINALLY GIVING IT THE
BOOT. THUS POPS WERE RAISED MONDAY THROUGH TUESDAY ESPECIALLY IN
LINCOLN COUNTY. DRIER AIR SHOULD FINALLY WORK IN FROM THE SOUTHWEST
AS THE FLOW ALOFT TURNS IN THAT DIRECTION AND THIS SHOULD CUT BACK
ON THE COVERAGE OF STORMS OUT THAT WAY. WITH LESS CLOUDS, TEMPS
SHOULD TREND BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...SHOWERS NEAR THE SPRING MOUNTAINS WILL
DIMINISH DURING THE LATE AFTERNOON AND EVENING. WINDS WILL DECREASE
TO AROUND 10 KTS FROM THE WEST-SOUTHWEST THROUGH LATE EVENING THEN
BECOME LIGHT DIURNAL PATTERNS EARLY THURSDAY MORNING. SCATTERED
SHOWERS AND THUNDERSTORMS WILL PERSIST IN THE BEATTY CORRIDOR
THROUGH LATE EVENING. ISOLATED THUNDERSTORMS WILL BE POSSIBLE
THURSDAY AFTERNOON AND EVENING OVER THE SPRING MOUNTAINS AND THE
BEATTY/MORMON MESA CORRIDORS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SCATTERED SHOWERS AND THUNDERSTORMS OVER NORTHERN
INYO...ESMERALDA AND CENTRAL NYE COUNTIES WILL PERSIST THROUGH THIS
EVENING THEN DIMINISH OVERNIGHT. WIND GUSTS OF 25-35 KTS WILL OCCUR
NEAR STORMS. SCT-BKN BASES AROUND 10 KFT MSL CAN BE EXPECTED WITH
MOUNTAIN TOP OBSCUREMENT. ISOLATED THUNDERSTORMS ELSEWHERE ACROSS
THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA WILL DISSIPATE EARLY
THIS EVENING. CONSIDERABLY LESS THUNDERSTORM COVERAGE IS EXPECTED
THURSDAY WITH ISOLATED STORMS CONFINED TO THE HIGHER MOUNTAINS AND
ONLY SCT BASES AROUND 12-15KFT MSL.
&&

.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.
&&

SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER








000
FXUS65 KVEF 301702
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1000 AM PDT WED JUL 30 2014

.SYNOPSIS...LIMITED SHOWER AND THUNDERSTORM DEVELOPMENT WILL BE
CONFINED PRIMARILY TO NORTHERN INYO COUNTY AND SOUTHERN GREAT BASIN
UNDER A DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH
FRIDAY. ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE
REGION OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.UPDATE...THE 12Z LAS VEGAS SOUNDING SHOWED SUFFICIENT MOISTURE AND
INSTABILITY FOR A THUNDERSTORM TO DEVELOP OVER THE MOUNTAINS WITH
ONLY A WEAK CAP TO OVERCOME ABOVE 700 MB. RECENT SATELLITE/RADAR
LOOPS AND WEB CAMS SHOW CONSIDERABLE CLOUD COVER AND SHOWERS
SPREADING INTO THE CENTRAL AND SOUTHERN SIERRA BUT NOT MUCH PRECIP
SPILLING OVER TO THE OWENS VALLEY YET. WE SHOULD SEE A COMBINATION
OF STRATIFORM PRECIP WITH ISOLATED EMBEDDED THUNDERSTORMS OVER
NORTHERN INYO COUNTY. RECENT ANALYSES SHOW FAIRLY DRY AND STABLE
CONDITIONS FROM NORTHERN SAN BERNARDINO AND CENTRAL CLARK COUNTY
SOUTHWARD. THE GOING FORECAST LOOKS GOOD AND NO IMMEDIATE CHANGES
PLANNED.
&&

.PREV DISCUSSION...
258 AM PDT WED JUL 30 2014

.SHORT TERM...THROUGH FRIDAY NIGHT...MOSTLY CLOUDY OVER THE SOUTHERN
SIERRA/WRN INYO COUNTY THIS MORNING WITH ISOLATED
SHOWERS/THUNDERSTORMS ALONG THE WESTERN FOOTHILLS. ELSEWHERE,
SATELLITE SHOWS MOSTLY CLEAR TO PARTLY CLOUDY SKIES.

THE SUBTROPICAL RIDGE AXIS WILL EXTEND FROM SOUTHERN CALIFORNIA
SOUTHEAST INTO SOUTH TEXAS TODAY AND THURSDAY. AREA OF INTEREST THE
COMING DAYS WILL BE AREA OF MOISTURE AND EMBEDDED WEAK DISTURBANCES
PROGGED TO STREAM THROUGH CENTRAL CALIFORNIA TODAY, THEN SPREAD
NORTHEAST ACROSS THE SOUTHERN SIERRA AND INTO CENTRAL NEVADA TONIGHT
AND THURSDAY. REMNANTS FROM HERNAN WILL ALSO INJECT SOME ADDITIONAL
MOISTURE INTO THE MIX. DID INCREASE POPS A BIT MORE OVER NORTHERN
INYO, ESMERALDA AND CENTRAL NYE COUNTIES TODAY BASED ON THE LATEST
HRRR. STILL LOOKS LIKE A FEW SHOWERS OR THUNDERSTORMS WILL CONTINUE
ACROSS CENTRAL NEVADA TONIGHT AND FRIDAY WITH UPPER LEVEL
DISTURBANCE. BY FRIDAY, RIDGE EXPANDS NORTH INTO THE NORTHERN
ROCKIES. RESIDUAL MOISTURE AND LIMITED INSTABILITY OVER THE AREA
SHOULD BE ENOUGH TO GENERATE A FEW THUNDERSTORMS OVER THE HIGHER
TERRAIN OF THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. DAYTIME
HIGHS WILL BE NEAR NORMAL THROUGH FRIDAY WHILE NO SIGNIFICANT WINDS
ARE EXPECTED.

.LONG TERM...SATURDAY THROUGH WEDNESDAY.

WELL GET READY FOR ANOTHER PUSH OF JUICIER MOISTURE THIS WEEKEND,
ESPECIALLY OVER THE EASTERN HALF OF THE AREA, AS THE FLOW ALOFT
TRANSITIONS TO THE SOUTHEAST BY SATURDAY MORNING ACROSS OUR AREA AS
THE CLASSIC SUMMERTIME FOUR CORNERS HIGH SETS BACK UP. AT LEAST
INITIALLY, IT APPEARS THAT WHATEVER SHOWER AND THUNDERSTORM ACTIVITY
THAT DEVELOPS ON SATURDAY AFTERNOON AND EVENING SHOULD DEVELOP
COURTESY OF ANY DIFFERENTIAL HEATING BOUNDARIES OR BE TERRAIN
INDUCED. THE LATEST ECMWF AND GFS ARE MORE STABLE OVER THE WESTERN
CWFA AND THUS IF THIS TREND CONTINUES WE MAY NEED TO TRIM POPS THERE
DOWN. PWAT VALUES PUSHING 1.50 INCHES WILL MEAN THE ATMOSPHERE WILL
HAVE A LOT OF JUICE AND THUS FLASH FLOODING WILL BE THE PRIMARY
THREAT IN STRONGER OR SLOWER MOVING STORMS.

THINGS GET MORE INTERESTING SATURDAY NIGHT THROUGH MONDAY AS AN
INVERTED TROUGH OR SOME SORT OF VORTICITY MAXIMUM OR LOBE HEADS
NORTHWEST FROM CENTRAL ARIZONA AND CROSSES THE AREA. THIS FEATURE
SHOULD LIFT SLOWLY NORTHEAST ON MONDAY BUT CONTINUES TO TREND TOWARD
A SLOWER EXIT ON THE MODELS. THE PRESENCE OF THIS FEATURE IS SHOWN
ON THE BIG 4 MEDIUM RANGE OPERATIONAL MODELS (GFS, ECMWF, GEM AND
DGEX) AND THIS TRIGGER FEATURE COMBINED WITH THE HIGH MOISTURE
CONTENT AVAILABLE SHOULD RESULT IN AN EVEN BETTER CHANCE FOR SHOWERS
AND THUNDERSTORMS EVEN AT NIGHT. POPS WERE RAISED AGAIN TO SHOW A
BETTER UPTICK IN ACTIVITY FOR SUNDAY THROUGH MONDAY. THE MAIN
CONCERN CONTINUES TO BE HOW MUCH CLOUD COVER EXISTS AS THIS WOULD
LIMIT HEATING AND RESULT IN MORE SHOWERS AND LOW-GRADE
THUNDERSTORMS. HOWEVER, IF WE GET ENOUGH HEATING SUNDAY, ACTIVITY
WOULD SUPPORT THE POTENTIAL FOR STRONGER THUNDERSTORMS WITH 0-6 KM
BULK SHEAR VALUES SHOWN BY THE GFS TO EXCEED 20 KTS ACROSS THE
EASTERN CWFA. HEAVY RAIN PRODUCING THUNDERSTORMS WILL BE THE MAIN
THREAT ALONG WITH THE RISK FOR FLASH FLOODING. HIGH TEMPS WILL BE
VERY TRICKY ESPECIALLY ON SUNDAY AS CLOUDS COULD EASILY HOLD TEMPS
DOWN ANOTHER 6-8 DEGREES FROM WHAT IS FORECAST.

THE LATEST MODELS NOW SHOW A SLOWER EXIT TO THIS FEATURE KEEPING IT
OVER THE NORTHEAST CWFA THROUGH TUESDAY BEFORE FINALLY GIVING IT THE
BOOT. THUS POPS WERE RAISED MONDAY THROUGH TUESDAY ESPECIALLY IN
LINCOLN COUNTY. DRIER AIR SHOULD FINALLY WORK IN FROM THE SOUTHWEST
AS THE FLOW ALOFT TURNS IN THAT DIRECTION AND THIS SHOULD CUT BACK
ON THE COVERAGE OF STORMS OUT THAT WAY. WITH LESS CLOUDS, TEMPS
SHOULD TREND BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...A LIGHT EASTERLY WIND COMPONENT SHOULD
PERSIST INTO LATE AFTERNOON BEFORE WINDS SHIFT BACK MORE
SOUTHWESTERLY. SCT-BKN CLOUD BASES ABOVE 15 KFT CAN BE EXPECTED.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN THE BEATTY AND MORMON
MESA CORRIDORS THIS AFTERNOON/EARLY EVENING.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR
MAINLY IN NORTHERN INYO...ESMERALDA AND CENTRAL NYE COUNTIES TODAY
AND TONIGHT. ISOLATED THUNDERSTORM DEVELOPMENT CAN BE EXPECTED
ELSEWHERE ACROSS THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. THE
REST OF THE REGION WILL SEE WINDS GENERALLY LESS THAN 15 KTS AND
SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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.
&&

UPDATE...ADAIR
PREV DISCUSSION...PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER










000
FXUS65 KVEF 301702
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1000 AM PDT WED JUL 30 2014

.SYNOPSIS...LIMITED SHOWER AND THUNDERSTORM DEVELOPMENT WILL BE
CONFINED PRIMARILY TO NORTHERN INYO COUNTY AND SOUTHERN GREAT BASIN
UNDER A DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH
FRIDAY. ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE
REGION OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.UPDATE...THE 12Z LAS VEGAS SOUNDING SHOWED SUFFICIENT MOISTURE AND
INSTABILITY FOR A THUNDERSTORM TO DEVELOP OVER THE MOUNTAINS WITH
ONLY A WEAK CAP TO OVERCOME ABOVE 700 MB. RECENT SATELLITE/RADAR
LOOPS AND WEB CAMS SHOW CONSIDERABLE CLOUD COVER AND SHOWERS
SPREADING INTO THE CENTRAL AND SOUTHERN SIERRA BUT NOT MUCH PRECIP
SPILLING OVER TO THE OWENS VALLEY YET. WE SHOULD SEE A COMBINATION
OF STRATIFORM PRECIP WITH ISOLATED EMBEDDED THUNDERSTORMS OVER
NORTHERN INYO COUNTY. RECENT ANALYSES SHOW FAIRLY DRY AND STABLE
CONDITIONS FROM NORTHERN SAN BERNARDINO AND CENTRAL CLARK COUNTY
SOUTHWARD. THE GOING FORECAST LOOKS GOOD AND NO IMMEDIATE CHANGES
PLANNED.
&&

.PREV DISCUSSION...
258 AM PDT WED JUL 30 2014

.SHORT TERM...THROUGH FRIDAY NIGHT...MOSTLY CLOUDY OVER THE SOUTHERN
SIERRA/WRN INYO COUNTY THIS MORNING WITH ISOLATED
SHOWERS/THUNDERSTORMS ALONG THE WESTERN FOOTHILLS. ELSEWHERE,
SATELLITE SHOWS MOSTLY CLEAR TO PARTLY CLOUDY SKIES.

THE SUBTROPICAL RIDGE AXIS WILL EXTEND FROM SOUTHERN CALIFORNIA
SOUTHEAST INTO SOUTH TEXAS TODAY AND THURSDAY. AREA OF INTEREST THE
COMING DAYS WILL BE AREA OF MOISTURE AND EMBEDDED WEAK DISTURBANCES
PROGGED TO STREAM THROUGH CENTRAL CALIFORNIA TODAY, THEN SPREAD
NORTHEAST ACROSS THE SOUTHERN SIERRA AND INTO CENTRAL NEVADA TONIGHT
AND THURSDAY. REMNANTS FROM HERNAN WILL ALSO INJECT SOME ADDITIONAL
MOISTURE INTO THE MIX. DID INCREASE POPS A BIT MORE OVER NORTHERN
INYO, ESMERALDA AND CENTRAL NYE COUNTIES TODAY BASED ON THE LATEST
HRRR. STILL LOOKS LIKE A FEW SHOWERS OR THUNDERSTORMS WILL CONTINUE
ACROSS CENTRAL NEVADA TONIGHT AND FRIDAY WITH UPPER LEVEL
DISTURBANCE. BY FRIDAY, RIDGE EXPANDS NORTH INTO THE NORTHERN
ROCKIES. RESIDUAL MOISTURE AND LIMITED INSTABILITY OVER THE AREA
SHOULD BE ENOUGH TO GENERATE A FEW THUNDERSTORMS OVER THE HIGHER
TERRAIN OF THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. DAYTIME
HIGHS WILL BE NEAR NORMAL THROUGH FRIDAY WHILE NO SIGNIFICANT WINDS
ARE EXPECTED.

.LONG TERM...SATURDAY THROUGH WEDNESDAY.

WELL GET READY FOR ANOTHER PUSH OF JUICIER MOISTURE THIS WEEKEND,
ESPECIALLY OVER THE EASTERN HALF OF THE AREA, AS THE FLOW ALOFT
TRANSITIONS TO THE SOUTHEAST BY SATURDAY MORNING ACROSS OUR AREA AS
THE CLASSIC SUMMERTIME FOUR CORNERS HIGH SETS BACK UP. AT LEAST
INITIALLY, IT APPEARS THAT WHATEVER SHOWER AND THUNDERSTORM ACTIVITY
THAT DEVELOPS ON SATURDAY AFTERNOON AND EVENING SHOULD DEVELOP
COURTESY OF ANY DIFFERENTIAL HEATING BOUNDARIES OR BE TERRAIN
INDUCED. THE LATEST ECMWF AND GFS ARE MORE STABLE OVER THE WESTERN
CWFA AND THUS IF THIS TREND CONTINUES WE MAY NEED TO TRIM POPS THERE
DOWN. PWAT VALUES PUSHING 1.50 INCHES WILL MEAN THE ATMOSPHERE WILL
HAVE A LOT OF JUICE AND THUS FLASH FLOODING WILL BE THE PRIMARY
THREAT IN STRONGER OR SLOWER MOVING STORMS.

THINGS GET MORE INTERESTING SATURDAY NIGHT THROUGH MONDAY AS AN
INVERTED TROUGH OR SOME SORT OF VORTICITY MAXIMUM OR LOBE HEADS
NORTHWEST FROM CENTRAL ARIZONA AND CROSSES THE AREA. THIS FEATURE
SHOULD LIFT SLOWLY NORTHEAST ON MONDAY BUT CONTINUES TO TREND TOWARD
A SLOWER EXIT ON THE MODELS. THE PRESENCE OF THIS FEATURE IS SHOWN
ON THE BIG 4 MEDIUM RANGE OPERATIONAL MODELS (GFS, ECMWF, GEM AND
DGEX) AND THIS TRIGGER FEATURE COMBINED WITH THE HIGH MOISTURE
CONTENT AVAILABLE SHOULD RESULT IN AN EVEN BETTER CHANCE FOR SHOWERS
AND THUNDERSTORMS EVEN AT NIGHT. POPS WERE RAISED AGAIN TO SHOW A
BETTER UPTICK IN ACTIVITY FOR SUNDAY THROUGH MONDAY. THE MAIN
CONCERN CONTINUES TO BE HOW MUCH CLOUD COVER EXISTS AS THIS WOULD
LIMIT HEATING AND RESULT IN MORE SHOWERS AND LOW-GRADE
THUNDERSTORMS. HOWEVER, IF WE GET ENOUGH HEATING SUNDAY, ACTIVITY
WOULD SUPPORT THE POTENTIAL FOR STRONGER THUNDERSTORMS WITH 0-6 KM
BULK SHEAR VALUES SHOWN BY THE GFS TO EXCEED 20 KTS ACROSS THE
EASTERN CWFA. HEAVY RAIN PRODUCING THUNDERSTORMS WILL BE THE MAIN
THREAT ALONG WITH THE RISK FOR FLASH FLOODING. HIGH TEMPS WILL BE
VERY TRICKY ESPECIALLY ON SUNDAY AS CLOUDS COULD EASILY HOLD TEMPS
DOWN ANOTHER 6-8 DEGREES FROM WHAT IS FORECAST.

THE LATEST MODELS NOW SHOW A SLOWER EXIT TO THIS FEATURE KEEPING IT
OVER THE NORTHEAST CWFA THROUGH TUESDAY BEFORE FINALLY GIVING IT THE
BOOT. THUS POPS WERE RAISED MONDAY THROUGH TUESDAY ESPECIALLY IN
LINCOLN COUNTY. DRIER AIR SHOULD FINALLY WORK IN FROM THE SOUTHWEST
AS THE FLOW ALOFT TURNS IN THAT DIRECTION AND THIS SHOULD CUT BACK
ON THE COVERAGE OF STORMS OUT THAT WAY. WITH LESS CLOUDS, TEMPS
SHOULD TREND BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...A LIGHT EASTERLY WIND COMPONENT SHOULD
PERSIST INTO LATE AFTERNOON BEFORE WINDS SHIFT BACK MORE
SOUTHWESTERLY. SCT-BKN CLOUD BASES ABOVE 15 KFT CAN BE EXPECTED.
ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN THE BEATTY AND MORMON
MESA CORRIDORS THIS AFTERNOON/EARLY EVENING.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR
MAINLY IN NORTHERN INYO...ESMERALDA AND CENTRAL NYE COUNTIES TODAY
AND TONIGHT. ISOLATED THUNDERSTORM DEVELOPMENT CAN BE EXPECTED
ELSEWHERE ACROSS THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. THE
REST OF THE REGION WILL SEE WINDS GENERALLY LESS THAN 15 KTS AND
SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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.
&&

UPDATE...ADAIR
PREV DISCUSSION...PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER









000
FXUS65 KVEF 300958
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
258 AM PDT WED JUL 30 2014

.SYNOPSIS...LIMITED SHOWER AND THUNDERSTORM DEVELOPMENT WILL BE
CONFINED PRIMARILY TO NORTHERN INYO COUNTY AND SOUTHERN GREAT BASIN
UNDER A DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH
FRIDAY. ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE
REGION OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.SHORT TERM...THROUGH FRIDAY NIGHT...MOSTLY CLOUDY OVER THE SOUTHERN
SIERRA/WRN INYO COUNTY THIS MORNING WITH ISOLATED
SHOWERS/THUNDERSTORMS ALONG THE WESTERN FOOTHILLS. ELSEWHERE,
SATELLITE SHOWS MOSTLY CLEAR TO PARTLY CLOUDY SKIES.

THE SUBTROPICAL RIDGE AXIS WILL EXTEND FROM SOUTHERN CALIFORNIA
SOUTHEAST INTO SOUTH TEXAS TODAY AND THURSDAY. AREA OF INTEREST THE
COMING DAYS WILL BE AREA OF MOISTURE AND EMBEDDED WEAK DISTURBANCES
PROGGED TO STREAM THROUGH CENTRAL CALIFORNIA TODAY, THEN SPREAD
NORTHEAST ACROSS THE SOUTHERN SIERRA AND INTO CENTRAL NEVADA TONIGHT
AND THURSDAY. REMNANTS FROM HERNAN WILL ALSO INJECT SOME ADDITIONAL
MOISTURE INTO THE MIX. DID INCREASE POPS A BIT MORE OVER NORTHERN
INYO, ESMERALDA AND CENTRAL NYE COUNTIES TODAY BASED ON THE LATEST
HRRR. STILL LOOKS LIKE A FEW SHOWERS OR THUNDERSTORMS WILL CONTINUE
ACROSS CENTRAL NEVADA TONIGHT AND FRIDAY WITH UPPER LEVEL
DISTURBANCE. BY FRIDAY, RIDGE EXPANDS NORTH INTO THE NORTHERN
ROCKIES. RESIDUAL MOISTURE AND LIMITED INSTABILITY OVER THE AREA
SHOULD BE ENOUGH TO GENERATE A FEW THUNDERSTORMS OVER THE HIGHER
TERRAIN OF THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. DAYTIME
HIGHS WILL BE NEAR NORMAL THROUGH FRIDAY WHILE NO SIGNIFICANT WINDS
ARE EXPECTED.

.LONG TERM...SATURDAY THROUGH WEDNESDAY.

WELL GET READY FOR ANOTHER PUSH OF JUICIER MOISTURE THIS WEEKEND,
ESPECIALLY OVER THE EASTERN HALF OF THE AREA, AS THE FLOW ALOFT
TRANSITIONS TO THE SOUTHEAST BY SATURDAY MORNING ACROSS OUR AREA AS
THE CLASSIC SUMMERTIME FOUR CORNERS HIGH SETS BACK UP. AT LEAST
INITIALLY, IT APPEARS THAT WHATEVER SHOWER AND THUNDERSTORM ACTIVITY
THAT DEVELOPS ON SATURDAY AFTERNOON AND EVENING SHOULD DEVELOP
COURTESY OF ANY DIFFERENTIAL HEATING BOUNDARIES OR BE TERRAIN
INDUCED. THE LATEST ECMWF AND GFS ARE MORE STABLE OVER THE WESTERN
CWFA AND THUS IF THIS TREND CONTINUES WE MAY NEED TO TRIM POPS THERE
DOWN. PWAT VALUES PUSHING 1.50 INCHES WILL MEAN THE ATMOSPHERE WILL
HAVE A LOT OF JUICE AND THUS FLASH FLOODING WILL BE THE PRIMARY
THREAT IN STRONGER OR SLOWER MOVING STORMS.

THINGS GET MORE INTERESTING SATURDAY NIGHT THROUGH MONDAY AS AN
INVERTED TROUGH OR SOME SORT OF VORTICITY MAXIMUM OR LOBE HEADS
NORTHWEST FROM CENTRAL ARIZONA AND CROSSES THE AREA. THIS FEATURE
SHOULD LIFT SLOWLY NORTHEAST ON MONDAY BUT CONTINUES TO TREND TOWARD
A SLOWER EXIT ON THE MODELS. THE PRESENCE OF THIS FEATURE IS SHOWN
ON THE BIG 4 MEDIUM RANGE OPERATIONAL MODELS (GFS, ECMWF, GEM AND
DGEX) AND THIS TRIGGER FEATURE COMBINED WITH THE HIGH MOISTURE
CONTENT AVAILABLE SHOULD RESULT IN AN EVEN BETTER CHANCE FOR SHOWERS
AND THUNDERSTORMS EVEN AT NIGHT. POPS WERE RAISED AGAIN TO SHOW A
BETTER UPTICK IN ACTIVITY FOR SUNDAY THROUGH MONDAY. THE MAIN
CONCERN CONTINUES TO BE HOW MUCH CLOUD COVER EXISTS AS THIS WOULD
LIMIT HEATING AND RESULT IN MORE SHOWERS AND LOW-GRADE
THUNDERSTORMS. HOWEVER, IF WE GET ENOUGH HEATING SUNDAY, ACTIVITY
WOULD SUPPORT THE POTENTIAL FOR STRONGER THUNDERSTORMS WITH 0-6 KM
BULK SHEAR VALUES SHOWN BY THE GFS TO EXCEED 20 KTS ACROSS THE
EASTERN CWFA. HEAVY RAIN PRODUCING THUNDERSTORMS WILL BE THE MAIN
THREAT ALONG WITH THE RISK FOR FLASH FLOODING. HIGH TEMPS WILL BE
VERY TRICKY ESPECIALLY ON SUNDAY AS CLOUDS COULD EASILY HOLD TEMPS
DOWN ANOTHER 6-8 DEGREES FROM WHAT IS FORECAST.

THE LATEST MODELS NOW SHOW A SLOWER EXIT TO THIS FEATURE KEEPING IT
OVER THE NORTHEAST CWFA THROUGH TUESDAY BEFORE FINALLY GIVING IT THE
BOOT. THUS POPS WERE RAISED MONDAY THROUGH TUESDAY ESPECIALLY IN
LINCOLN COUNTY. DRIER AIR SHOULD FINALLY WORK IN FROM THE SOUTHWEST
AS THE FLOW ALOFT TURNS IN THAT DIRECTION AND THIS SHOULD CUT BACK
ON THE COVERAGE OF STORMS OUT THAT WAY. WITH LESS CLOUDS, TEMPS
SHOULD TREND BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...PREVAILING SOUTHWEST WINDS AROUND 10
KNOTS WILL PERSIST INTO THE MORNING THEN A LIGHT EASTERLY WIND
COMPONENT SHOULD DEVELOP LATE MORNING AND PERSIST INTO THE EVENING
BEFORE WINDS SHIFT BACK MORE SOUTHWESTERLY. SCT-BKN CLOUD BASES
ABOVE 15 KFT CAN BE EXPECTED. ISOLATED THUNDERSTORMS WILL BE
POSSIBLE IN THE BEATTY AND MORMON MESA CORRIDORS THIS
AFTERNOON/EARLY EVENING.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR
MAINLY IN NORTHERN INYO...ESMERALDA AND CENTRAL NYE COUNTIES TODAY
AND TONIGHT. ISOLATED THUNDERSTORM DEVELOPMENT CAN BE EXPECTED
ELSEWHERE ACROSS THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. THE
REST OF THE REGION WILL SEE WINDS GENERALLY LESS THAN 15 KTS AND
SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER






000
FXUS65 KVEF 300958
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
258 AM PDT WED JUL 30 2014

.SYNOPSIS...LIMITED SHOWER AND THUNDERSTORM DEVELOPMENT WILL BE
CONFINED PRIMARILY TO NORTHERN INYO COUNTY AND SOUTHERN GREAT BASIN
UNDER A DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH
FRIDAY. ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE
REGION OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.SHORT TERM...THROUGH FRIDAY NIGHT...MOSTLY CLOUDY OVER THE SOUTHERN
SIERRA/WRN INYO COUNTY THIS MORNING WITH ISOLATED
SHOWERS/THUNDERSTORMS ALONG THE WESTERN FOOTHILLS. ELSEWHERE,
SATELLITE SHOWS MOSTLY CLEAR TO PARTLY CLOUDY SKIES.

THE SUBTROPICAL RIDGE AXIS WILL EXTEND FROM SOUTHERN CALIFORNIA
SOUTHEAST INTO SOUTH TEXAS TODAY AND THURSDAY. AREA OF INTEREST THE
COMING DAYS WILL BE AREA OF MOISTURE AND EMBEDDED WEAK DISTURBANCES
PROGGED TO STREAM THROUGH CENTRAL CALIFORNIA TODAY, THEN SPREAD
NORTHEAST ACROSS THE SOUTHERN SIERRA AND INTO CENTRAL NEVADA TONIGHT
AND THURSDAY. REMNANTS FROM HERNAN WILL ALSO INJECT SOME ADDITIONAL
MOISTURE INTO THE MIX. DID INCREASE POPS A BIT MORE OVER NORTHERN
INYO, ESMERALDA AND CENTRAL NYE COUNTIES TODAY BASED ON THE LATEST
HRRR. STILL LOOKS LIKE A FEW SHOWERS OR THUNDERSTORMS WILL CONTINUE
ACROSS CENTRAL NEVADA TONIGHT AND FRIDAY WITH UPPER LEVEL
DISTURBANCE. BY FRIDAY, RIDGE EXPANDS NORTH INTO THE NORTHERN
ROCKIES. RESIDUAL MOISTURE AND LIMITED INSTABILITY OVER THE AREA
SHOULD BE ENOUGH TO GENERATE A FEW THUNDERSTORMS OVER THE HIGHER
TERRAIN OF THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. DAYTIME
HIGHS WILL BE NEAR NORMAL THROUGH FRIDAY WHILE NO SIGNIFICANT WINDS
ARE EXPECTED.

.LONG TERM...SATURDAY THROUGH WEDNESDAY.

WELL GET READY FOR ANOTHER PUSH OF JUICIER MOISTURE THIS WEEKEND,
ESPECIALLY OVER THE EASTERN HALF OF THE AREA, AS THE FLOW ALOFT
TRANSITIONS TO THE SOUTHEAST BY SATURDAY MORNING ACROSS OUR AREA AS
THE CLASSIC SUMMERTIME FOUR CORNERS HIGH SETS BACK UP. AT LEAST
INITIALLY, IT APPEARS THAT WHATEVER SHOWER AND THUNDERSTORM ACTIVITY
THAT DEVELOPS ON SATURDAY AFTERNOON AND EVENING SHOULD DEVELOP
COURTESY OF ANY DIFFERENTIAL HEATING BOUNDARIES OR BE TERRAIN
INDUCED. THE LATEST ECMWF AND GFS ARE MORE STABLE OVER THE WESTERN
CWFA AND THUS IF THIS TREND CONTINUES WE MAY NEED TO TRIM POPS THERE
DOWN. PWAT VALUES PUSHING 1.50 INCHES WILL MEAN THE ATMOSPHERE WILL
HAVE A LOT OF JUICE AND THUS FLASH FLOODING WILL BE THE PRIMARY
THREAT IN STRONGER OR SLOWER MOVING STORMS.

THINGS GET MORE INTERESTING SATURDAY NIGHT THROUGH MONDAY AS AN
INVERTED TROUGH OR SOME SORT OF VORTICITY MAXIMUM OR LOBE HEADS
NORTHWEST FROM CENTRAL ARIZONA AND CROSSES THE AREA. THIS FEATURE
SHOULD LIFT SLOWLY NORTHEAST ON MONDAY BUT CONTINUES TO TREND TOWARD
A SLOWER EXIT ON THE MODELS. THE PRESENCE OF THIS FEATURE IS SHOWN
ON THE BIG 4 MEDIUM RANGE OPERATIONAL MODELS (GFS, ECMWF, GEM AND
DGEX) AND THIS TRIGGER FEATURE COMBINED WITH THE HIGH MOISTURE
CONTENT AVAILABLE SHOULD RESULT IN AN EVEN BETTER CHANCE FOR SHOWERS
AND THUNDERSTORMS EVEN AT NIGHT. POPS WERE RAISED AGAIN TO SHOW A
BETTER UPTICK IN ACTIVITY FOR SUNDAY THROUGH MONDAY. THE MAIN
CONCERN CONTINUES TO BE HOW MUCH CLOUD COVER EXISTS AS THIS WOULD
LIMIT HEATING AND RESULT IN MORE SHOWERS AND LOW-GRADE
THUNDERSTORMS. HOWEVER, IF WE GET ENOUGH HEATING SUNDAY, ACTIVITY
WOULD SUPPORT THE POTENTIAL FOR STRONGER THUNDERSTORMS WITH 0-6 KM
BULK SHEAR VALUES SHOWN BY THE GFS TO EXCEED 20 KTS ACROSS THE
EASTERN CWFA. HEAVY RAIN PRODUCING THUNDERSTORMS WILL BE THE MAIN
THREAT ALONG WITH THE RISK FOR FLASH FLOODING. HIGH TEMPS WILL BE
VERY TRICKY ESPECIALLY ON SUNDAY AS CLOUDS COULD EASILY HOLD TEMPS
DOWN ANOTHER 6-8 DEGREES FROM WHAT IS FORECAST.

THE LATEST MODELS NOW SHOW A SLOWER EXIT TO THIS FEATURE KEEPING IT
OVER THE NORTHEAST CWFA THROUGH TUESDAY BEFORE FINALLY GIVING IT THE
BOOT. THUS POPS WERE RAISED MONDAY THROUGH TUESDAY ESPECIALLY IN
LINCOLN COUNTY. DRIER AIR SHOULD FINALLY WORK IN FROM THE SOUTHWEST
AS THE FLOW ALOFT TURNS IN THAT DIRECTION AND THIS SHOULD CUT BACK
ON THE COVERAGE OF STORMS OUT THAT WAY. WITH LESS CLOUDS, TEMPS
SHOULD TREND BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...PREVAILING SOUTHWEST WINDS AROUND 10
KNOTS WILL PERSIST INTO THE MORNING THEN A LIGHT EASTERLY WIND
COMPONENT SHOULD DEVELOP LATE MORNING AND PERSIST INTO THE EVENING
BEFORE WINDS SHIFT BACK MORE SOUTHWESTERLY. SCT-BKN CLOUD BASES
ABOVE 15 KFT CAN BE EXPECTED. ISOLATED THUNDERSTORMS WILL BE
POSSIBLE IN THE BEATTY AND MORMON MESA CORRIDORS THIS
AFTERNOON/EARLY EVENING.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED/SCATTERED SHOWERS AND THUNDERSTORMS WILL OCCUR
MAINLY IN NORTHERN INYO...ESMERALDA AND CENTRAL NYE COUNTIES TODAY
AND TONIGHT. ISOLATED THUNDERSTORM DEVELOPMENT CAN BE EXPECTED
ELSEWHERE ACROSS THE SOUTHERN GREAT BASIN AND NORTHWEST ARIZONA. THE
REST OF THE REGION WILL SEE WINDS GENERALLY LESS THAN 15 KTS AND
SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER







000
FXUS65 KVEF 300411
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
911 PM PDT TUE JUL 29 2014

.SYNOPSIS...LIMITED THUNDERSTORM DEVELOPMENT WILL BE CONFINED
PRIMARILY TO THE SOUTHERN SIERRA AND SOUTHERN GREAT BASIN UNDER A
DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH FRIDAY.
ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE REGION
OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.UPDATE...
OVERALL THE FORECAST IS ON TRACK TONIGHT...ONLY MADE A FEW MINOR
ADJUSTMENTS TO THE NEAR TERM FORECAST. WE HAVE BEEN WATCHING AN
OUTFLOW BOUNDARY MOVE INTO NORTHERN LINCOLN COUNTY FROM THE NORTH.
GUSTY NORTH WINDS OF 51 MPH WERE REPORTED AT KELY ABOUT 2 HOURS AGO.
THE BOUNDARY APPEARS TO BE WEAKENING AS IT SAGS SOUTH...WITH OTHER
OBSERVATIONS ONLY GUSTING IN THE 30-40 MPH RANGE. THIS BOUNDARY MAY
SPARK A FEW SHOWERS ACROSS LINCOLN COUNTY BUT NOT REALLY SEEING MUCH
LIGHTNING ANYMORE. CLOUD TOPS ARE NOT COOLING LIKE THEY WERE FARTHER
NORTH DURING A TIME OF GREATER INSTABILITY. WITHOUT ADDITIONAL
CONVECTION TO SUSTAIN MOMENTUM...EXPECT THIS BOUNDARY TO CONTINUE
WEAKENING WITH SOUTHWARD PROGRESSION. HIGH RES MODELS HAVE IT
WASHING OUT AROUND THE CLARK-LINCOLN COUNTY LINE OVERNIGHT.
&&

.PREVIOUS DISCUSSION...
320 PM PDT TUE JUL 29 2014

.SHORT TERM...THROUGH THURSDAY NIGHT...THUNDERSTORMS HAVE BEEN
SUBDUED TODAY AND LITTLE DEVELOPMENT IS EXPECTED THROUGH THE REST OF
THE AFTERNOON AND EVENING EXCEPT POSSIBLY OVER THE SOUTHERN SIERRA
AND SOUTH CENTRAL NEVADA. AN 18Z LAS VEGAS SOUNDING SHOWED A MARKED
INCREASE IN STABILITY WITH A NOTICEABLE CAP IN THE 650-500 MB LAYER
AND SLIGHTLY DRYING IN THE 700-500 MB LAYER. IN ADDITION...
INCREASING WEST TO NORTHWEST FLOW ON THE BACK SIDE OF THE THE BROAD
CIRCULATION LIFTING UP THROUGH UTAH HAS ACTED TO SHEAR CONVECTION
DEVELOPING OVER THE MOUNTAINS. THE PATTERN WILL NOT CHANGE MUCH
WEDNESDAY AND THURSDAY AS A DRY AND SOMEWHAT MODERATELY STABLE WEST
TO SOUTHWEST FLOW REMAINS OVER THE SOUTHERN HALF OF THE AREA.
SUFFICIENT MOISTURE AND INSTABILITY WILL REMAIN OVER THE SOUTHERN
SIERRA AND SOUTH CENTRAL NEVADA FOR A FEW THUNDERSTORMS TO DEVELOP
EACH AFTERNOON AND EVENING. ONE OTHER FEATURE TO WATCH IS
POST-TROPICAL CYCLONE HERNAN MOVING NORTHWARD HUNDREDS OF MILE WEST
OF THE BAJA SPUR. THE REMNANT MID AND HIGH LEVEL MOISTURE IS
FORECAST TO SPREAD ACROSS SOUTHERN CALIFORNIA AND THE SOUTHERN
SIERRA THROUGH WEDNESDAY NIGHT. THIS SHOULD LEAD TO A LITTLE
INJECTION OF MOISTURE TO FUEL SHOWERS OVER THE SIERRA WEDNESDAY. THE
REST OF THE REGION SHOULD JUST SEE ADDITIONAL MID TO HIGH LEVEL
CLOUDS.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...PREVAILING SOUTHWEST WINDS AROUND 10
KNOTS WILL PERSIST OVERNIGHT THEN A LIGHT EASTERLY WIND COMPONENT
SHOULD DEVELOP LATE WEDNESDAY MORNING. SCT-BKN CLOUD BASES ABOVE 10
KFT CAN BE EXPECTED. ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN THE
BEATTY AND MORMON MESA CORRIDORS WEDNESDAY AFTERNOON.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...AFTERNOON AND EVENING ISOLATED THUNDERSTORM DEVELOPMENT
WILL BE LIMITED TO THE SOUTHERN SIERRA...SOUTH CENTRAL NEVADA AND
NORTHWEST THROUGH WEDNESDAY. THE REST OF THE REGION WILL SEE WINDS
GENERALLY LESS THAN 15 KNOTS AND SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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.
&&

UPDATE...PADDOCK
SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER















000
FXUS65 KVEF 300411
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
911 PM PDT TUE JUL 29 2014

.SYNOPSIS...LIMITED THUNDERSTORM DEVELOPMENT WILL BE CONFINED
PRIMARILY TO THE SOUTHERN SIERRA AND SOUTHERN GREAT BASIN UNDER A
DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH FRIDAY.
ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE REGION
OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.UPDATE...
OVERALL THE FORECAST IS ON TRACK TONIGHT...ONLY MADE A FEW MINOR
ADJUSTMENTS TO THE NEAR TERM FORECAST. WE HAVE BEEN WATCHING AN
OUTFLOW BOUNDARY MOVE INTO NORTHERN LINCOLN COUNTY FROM THE NORTH.
GUSTY NORTH WINDS OF 51 MPH WERE REPORTED AT KELY ABOUT 2 HOURS AGO.
THE BOUNDARY APPEARS TO BE WEAKENING AS IT SAGS SOUTH...WITH OTHER
OBSERVATIONS ONLY GUSTING IN THE 30-40 MPH RANGE. THIS BOUNDARY MAY
SPARK A FEW SHOWERS ACROSS LINCOLN COUNTY BUT NOT REALLY SEEING MUCH
LIGHTNING ANYMORE. CLOUD TOPS ARE NOT COOLING LIKE THEY WERE FARTHER
NORTH DURING A TIME OF GREATER INSTABILITY. WITHOUT ADDITIONAL
CONVECTION TO SUSTAIN MOMENTUM...EXPECT THIS BOUNDARY TO CONTINUE
WEAKENING WITH SOUTHWARD PROGRESSION. HIGH RES MODELS HAVE IT
WASHING OUT AROUND THE CLARK-LINCOLN COUNTY LINE OVERNIGHT.
&&

.PREVIOUS DISCUSSION...
320 PM PDT TUE JUL 29 2014

.SHORT TERM...THROUGH THURSDAY NIGHT...THUNDERSTORMS HAVE BEEN
SUBDUED TODAY AND LITTLE DEVELOPMENT IS EXPECTED THROUGH THE REST OF
THE AFTERNOON AND EVENING EXCEPT POSSIBLY OVER THE SOUTHERN SIERRA
AND SOUTH CENTRAL NEVADA. AN 18Z LAS VEGAS SOUNDING SHOWED A MARKED
INCREASE IN STABILITY WITH A NOTICEABLE CAP IN THE 650-500 MB LAYER
AND SLIGHTLY DRYING IN THE 700-500 MB LAYER. IN ADDITION...
INCREASING WEST TO NORTHWEST FLOW ON THE BACK SIDE OF THE THE BROAD
CIRCULATION LIFTING UP THROUGH UTAH HAS ACTED TO SHEAR CONVECTION
DEVELOPING OVER THE MOUNTAINS. THE PATTERN WILL NOT CHANGE MUCH
WEDNESDAY AND THURSDAY AS A DRY AND SOMEWHAT MODERATELY STABLE WEST
TO SOUTHWEST FLOW REMAINS OVER THE SOUTHERN HALF OF THE AREA.
SUFFICIENT MOISTURE AND INSTABILITY WILL REMAIN OVER THE SOUTHERN
SIERRA AND SOUTH CENTRAL NEVADA FOR A FEW THUNDERSTORMS TO DEVELOP
EACH AFTERNOON AND EVENING. ONE OTHER FEATURE TO WATCH IS
POST-TROPICAL CYCLONE HERNAN MOVING NORTHWARD HUNDREDS OF MILE WEST
OF THE BAJA SPUR. THE REMNANT MID AND HIGH LEVEL MOISTURE IS
FORECAST TO SPREAD ACROSS SOUTHERN CALIFORNIA AND THE SOUTHERN
SIERRA THROUGH WEDNESDAY NIGHT. THIS SHOULD LEAD TO A LITTLE
INJECTION OF MOISTURE TO FUEL SHOWERS OVER THE SIERRA WEDNESDAY. THE
REST OF THE REGION SHOULD JUST SEE ADDITIONAL MID TO HIGH LEVEL
CLOUDS.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...PREVAILING SOUTHWEST WINDS AROUND 10
KNOTS WILL PERSIST OVERNIGHT THEN A LIGHT EASTERLY WIND COMPONENT
SHOULD DEVELOP LATE WEDNESDAY MORNING. SCT-BKN CLOUD BASES ABOVE 10
KFT CAN BE EXPECTED. ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN THE
BEATTY AND MORMON MESA CORRIDORS WEDNESDAY AFTERNOON.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...AFTERNOON AND EVENING ISOLATED THUNDERSTORM DEVELOPMENT
WILL BE LIMITED TO THE SOUTHERN SIERRA...SOUTH CENTRAL NEVADA AND
NORTHWEST THROUGH WEDNESDAY. THE REST OF THE REGION WILL SEE WINDS
GENERALLY LESS THAN 15 KNOTS AND SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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.
&&

UPDATE...PADDOCK
SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER
















000
FXUS65 KVEF 292220
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
320 PM PDT TUE JUL 29 2014

.SYNOPSIS...LIMITED THUNDERSTORM DEVELOPMENT WILL BE CONFINED
PRIMARILY TO THE SOUTHERN SIERRA AND SOUTHERN GREAT BASIN UNDER A
DRIER AND MORE STABLE WEST TO SOUTHWEST FLOW ALOFT THROUGH FRIDAY.
ANOTHER PUSH OF MOISTURE IS EXPECTED TO SPREAD UP ACROSS THE REGION
OVER THE WEEKEND FOR AN UPSWING IN SHOWERS AND THUNDERSTORMS.
&&

.SHORT TERM...THROUGH THURSDAY NIGHT...THUNDERSTORMS HAVE BEEN
SUBDUED TODAY AND LITTLE DEVELOPMENT IS EXPECTED THROUGH THE REST OF
THE AFTERNOON AND EVENING EXCEPT POSSIBLY OVER THE SOUTHERN SIERRA
AND SOUTH CENTRAL NEVADA. AN 18Z LAS VEGAS SOUNDING SHOWED A MARKED
INCREASE IN STABILITY WITH A NOTICEABLE CAP IN THE 650-500 MB LAYER
AND SLIGHTLY DRYING IN THE 700-500 MB LAYER. IN ADDITION...
INCREASING WEST TO NORTHWEST FLOW ON THE BACK SIDE OF THE THE BROAD
CIRCULATION LIFTING UP THROUGH UTAH HAS ACTED TO SHEAR CONVECTION
DEVELOPING OVER THE MOUNTAINS. THE PATTERN WILL NOT CHANGE MUCH
WEDNESDAY AND THURSDAY AS A DRY AND SOMEWHAT MODERATELY STABLE WEST
TO SOUTHWEST FLOW REMAINS OVER THE SOUTHERN HALF OF THE AREA.
SUFFICIENT MOISTURE AND INSTABILITY WILL REMAIN OVER THE SOUTHERN
SIERRA AND SOUTH CENTRAL NEVADA FOR A FEW THUNDERSTORMS TO DEVELOP
EACH AFTERNOON AND EVENING. ONE OTHER FEATURE TO WATCH IS
POST-TROPICAL CYCLONE HERNAN MOVING NORTHWARD HUNDREDS OF MILE WEST
OF THE BAJA SPUR. THE REMNANT MID AND HIGH LEVEL MOISTURE IS
FORECAST TO SPREAD ACROSS SOUTHERN CALIFORNIA AND THE SOUTHERN
SIERRA THROUGH WEDNESDAY NIGHT. THIS SHOULD LEAD TO A LITTLE
INJECTION OF MOISTURE TO FUEL SHOWERS OVER THE SIERRA WEDNESDAY. THE
REST OF THE REGION SHOULD JUST SEE ADDITIONAL MID TO HIGH LEVEL
CLOUDS.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...PREVAILING SOUTHWEST WINDS AROUND 10
KNOTS WILL PERSIST OVERNIGHT THEN A LIGHT EASTERLY WIND COMPONENT
SHOULD DEVELOP LATE WEDNESDAY MORNING. SCT-BKN CLOUD BASES ABOVE 10
KFT CAN BE EXPECTED. ISOLATED THUNDERSTORMS WILL BE POSSIBLE IN THE
BEATTY AND MORMON MESA CORRIDORS WEDNESDAY AFTERNOON.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...AFTERNOON AND EVENING ISOLATED THUNDERSTORM DEVELOPMENT
WILL BE LIMITED TO THE SOUTHERN SIERRA...SOUTH CENTRAL NEVADA AND
NORTHWEST THROUGH WEDNESDAY. THE REST OF THE REGION WILL SEE WINDS
GENERALLY LESS THAN 15 KNOTS AND SCT-BKN MID TO HIGH LEVEL CLOUDS.
&&

.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.
&&

SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER












000
FXUS65 KVEF 291713
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1013 AM PDT TUE JUL 29 2014

.SYNOPSIS...MONSOON MOISTURE WILL REMAIN IN PLACE MAINLY ACROSS
NORTHWEST ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO
ISOLATED THUNDERSTORMS MAINLY CONFINED TO THE HIGHER TERRAIN.
TEMPERATURES WILL RETURN TO NEAR NORMAL WEDNESDAY AND THURSDAY.
THERE STILL LOOKS TO BE AN UPSWING IN THUNDERSTORMS OVER THE WEEKEND.
&&

.UPDATE...PRECIPITABLE WATER SENSORS AROUND MUCH OF THE REGION WERE
STILL INDICATING VALUES OF 1.25-1.50 INCHES AND THE 12Z LAS VEGAS
SOUNDING REVEALED SIGNIFICANT INSTABILITY WITH CAPE VALUES AROUND
2000 J/KG AND A LIFTED INDEX AROUND -5. THIS ENVIRONMENT WILL STILL
FAVOR HEAVY RAIN PRODUCING THUNDERSTORMS. THE ONLY APPARENT DYNAMIC
FORCING MECHANISM TODAY WAS A CIRCULATION OVER CENTRAL NEVADA THAT
WAS HELPING SUSTAIN A CONVECTIVE COMPLEX OVER LINCOLN COUNTY THIS
MORNING AS IT LIFTS TOWARD WEST CENTRAL UTAH. DIFFERENTIAL HEATING
AND OROGRAPHICS WILL SERVE AS THE MAIN LIFTING SOURCE FOR THE REST
OF THE REGION. INCREASING WESTERLY FLOW ALOFT WILL SOMEWHAT IMPEDE
SUSTAINED UPDRAFT DEVELOPMENT OVER THE MOUNTAINS BUT THUNDERSTORMS
SHOULD DEVELOP BY EARLY AFTERNOON THEN PUSH TO THE EAST AND
SOUTHEAST AS FLOW ALOFT INCREASES FROM THE WEST TO NORTHWEST. POPS
WERE INCREASED FOR THE SPRING MOUNTAINS AND WEST AND NORTHWEST PARTS
OF THE LAS VEGAS VALLEY BUT THIS SETUP SHOULD NOT ELEVATE THE FLASH
FLOOD THREAT.
&&

.PREV DISCUSSION...
343 AM PDT TUE JUL 29 2014

.SHORT TERM...THROUGH THURSDAY NIGHT...
WATER VAPOR SHOWS A SHORTWAVE LIFTING NORTHEAST INTO SOUTHWEST UTAH
WITH AN ANTICYCLONIC CIRCULATION OVER NORTHWEST NEVADA EARLY THIS
MORNING. AN AREA OF CONVERGENCE/DEFORMATION BETWEEN THESE TWO
SYSTEMS IS ROUGHLY ALIGNED FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. RADAR/SURFACE OBSERVATIONS SHOWING LIGHT
RAIN SHOWERS IN THIS BOUNDARY FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. SINCE MIDNIGHT, TWO SITES IN ESMERALDA
COUNTY (GOLDFIELD AND DYER) HAVE RECORDED AROUND A TENTH OF AN INCH.
OTHERWISE, RAINFALL TOTALS HAVE AMOUNTED TO ONLY A FEW HUNDREDTHS.

THE BOUNDARY IS PROGGED TO GRADUALLY WEAKEN THROUGHOUT THE DAY BUT
WE ARE STILL EXPECTING ANOTHER DAY OF TERRAIN DRIVEN CONVECTION.
REGIONAL INTEGRATED PRECIPITABLE WATER VALUES HAVE CHANGED LITTLE
FROM YESTERDAY BUT THAT SHOULD CHANGE THROUGHOUT THE DAY AS SOME
DRIER AIR MOVES IN FROM THE SOUTHWEST. SINCE WE ARE NOT LOOKING AT
THE AREAL COVERAGE OF STORMS COMPARED TO YESTERDAY WILL NOT BE GOING
WITH ANY WATCH. THAT SAID, LOCALLY HEAVY RAIN WOULD BE THE PRIMARY
CONCERN WITH ANY THUNDERSTORM. NAM THE PREFERRED MODEL CONTINUES TO
ADVERTISE SLOW DRYING LEADING TO A GRADUAL DECREASE IN TERRAIN
DRIVEN THUNDERSTORM COVERAGE WEDNESDAY AND THURSDAY.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...SCATTERED SHOWERS AND THUNDERSTORMS WILL
BE CONFINED MAINLY TO THE SURROUNDING MOUNTAINS THIS AFTERNOON AND
EVENING. ONCE DEVELOPED STORMS WILL LIKELY IMPACT ALL THE CORRIDORS
AT SOME POINT. WINDS WILL FAVOR SOUTHERLY OVERNIGHT BEFORE BECOMING
LIGHT AND VARIABLE. SOUTHERLY WINDS WILL RETURN BY LATE AFTERNOON
WITH THE POTENTIAL OF OUTFLOW WIND AFFECTING ALL LAS VEGAS VALLEY
TERMINALS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...RAIN SHOWERS WILL PERSIST FROM NORTHERN INYO COUNTY
THROUGH SOUTH CENTRAL NEVADA INTO THE MORNING. TYPICAL SOUTHERLY
WINDS WITH A FEW GUSTS ARE EXPECTED THIS AFTERNOON. ISOLATED TO
SCATTERED THUNDERSTORMS ARE ONCE AGAIN POSSIBLE ACROSS INYO
COUNTY...SOUTHERN NEVADA...AND NORTHWEST ARIZONA.
&&

.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.
&&

UPDATE...ADAIR
PREV DISCUSSION...PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER









000
FXUS65 KVEF 291713
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1013 AM PDT TUE JUL 29 2014

.SYNOPSIS...MONSOON MOISTURE WILL REMAIN IN PLACE MAINLY ACROSS
NORTHWEST ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO
ISOLATED THUNDERSTORMS MAINLY CONFINED TO THE HIGHER TERRAIN.
TEMPERATURES WILL RETURN TO NEAR NORMAL WEDNESDAY AND THURSDAY.
THERE STILL LOOKS TO BE AN UPSWING IN THUNDERSTORMS OVER THE WEEKEND.
&&

.UPDATE...PRECIPITABLE WATER SENSORS AROUND MUCH OF THE REGION WERE
STILL INDICATING VALUES OF 1.25-1.50 INCHES AND THE 12Z LAS VEGAS
SOUNDING REVEALED SIGNIFICANT INSTABILITY WITH CAPE VALUES AROUND
2000 J/KG AND A LIFTED INDEX AROUND -5. THIS ENVIRONMENT WILL STILL
FAVOR HEAVY RAIN PRODUCING THUNDERSTORMS. THE ONLY APPARENT DYNAMIC
FORCING MECHANISM TODAY WAS A CIRCULATION OVER CENTRAL NEVADA THAT
WAS HELPING SUSTAIN A CONVECTIVE COMPLEX OVER LINCOLN COUNTY THIS
MORNING AS IT LIFTS TOWARD WEST CENTRAL UTAH. DIFFERENTIAL HEATING
AND OROGRAPHICS WILL SERVE AS THE MAIN LIFTING SOURCE FOR THE REST
OF THE REGION. INCREASING WESTERLY FLOW ALOFT WILL SOMEWHAT IMPEDE
SUSTAINED UPDRAFT DEVELOPMENT OVER THE MOUNTAINS BUT THUNDERSTORMS
SHOULD DEVELOP BY EARLY AFTERNOON THEN PUSH TO THE EAST AND
SOUTHEAST AS FLOW ALOFT INCREASES FROM THE WEST TO NORTHWEST. POPS
WERE INCREASED FOR THE SPRING MOUNTAINS AND WEST AND NORTHWEST PARTS
OF THE LAS VEGAS VALLEY BUT THIS SETUP SHOULD NOT ELEVATE THE FLASH
FLOOD THREAT.
&&

.PREV DISCUSSION...
343 AM PDT TUE JUL 29 2014

.SHORT TERM...THROUGH THURSDAY NIGHT...
WATER VAPOR SHOWS A SHORTWAVE LIFTING NORTHEAST INTO SOUTHWEST UTAH
WITH AN ANTICYCLONIC CIRCULATION OVER NORTHWEST NEVADA EARLY THIS
MORNING. AN AREA OF CONVERGENCE/DEFORMATION BETWEEN THESE TWO
SYSTEMS IS ROUGHLY ALIGNED FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. RADAR/SURFACE OBSERVATIONS SHOWING LIGHT
RAIN SHOWERS IN THIS BOUNDARY FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. SINCE MIDNIGHT, TWO SITES IN ESMERALDA
COUNTY (GOLDFIELD AND DYER) HAVE RECORDED AROUND A TENTH OF AN INCH.
OTHERWISE, RAINFALL TOTALS HAVE AMOUNTED TO ONLY A FEW HUNDREDTHS.

THE BOUNDARY IS PROGGED TO GRADUALLY WEAKEN THROUGHOUT THE DAY BUT
WE ARE STILL EXPECTING ANOTHER DAY OF TERRAIN DRIVEN CONVECTION.
REGIONAL INTEGRATED PRECIPITABLE WATER VALUES HAVE CHANGED LITTLE
FROM YESTERDAY BUT THAT SHOULD CHANGE THROUGHOUT THE DAY AS SOME
DRIER AIR MOVES IN FROM THE SOUTHWEST. SINCE WE ARE NOT LOOKING AT
THE AREAL COVERAGE OF STORMS COMPARED TO YESTERDAY WILL NOT BE GOING
WITH ANY WATCH. THAT SAID, LOCALLY HEAVY RAIN WOULD BE THE PRIMARY
CONCERN WITH ANY THUNDERSTORM. NAM THE PREFERRED MODEL CONTINUES TO
ADVERTISE SLOW DRYING LEADING TO A GRADUAL DECREASE IN TERRAIN
DRIVEN THUNDERSTORM COVERAGE WEDNESDAY AND THURSDAY.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...SCATTERED SHOWERS AND THUNDERSTORMS WILL
BE CONFINED MAINLY TO THE SURROUNDING MOUNTAINS THIS AFTERNOON AND
EVENING. ONCE DEVELOPED STORMS WILL LIKELY IMPACT ALL THE CORRIDORS
AT SOME POINT. WINDS WILL FAVOR SOUTHERLY OVERNIGHT BEFORE BECOMING
LIGHT AND VARIABLE. SOUTHERLY WINDS WILL RETURN BY LATE AFTERNOON
WITH THE POTENTIAL OF OUTFLOW WIND AFFECTING ALL LAS VEGAS VALLEY
TERMINALS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...RAIN SHOWERS WILL PERSIST FROM NORTHERN INYO COUNTY
THROUGH SOUTH CENTRAL NEVADA INTO THE MORNING. TYPICAL SOUTHERLY
WINDS WITH A FEW GUSTS ARE EXPECTED THIS AFTERNOON. ISOLATED TO
SCATTERED THUNDERSTORMS ARE ONCE AGAIN POSSIBLE ACROSS INYO
COUNTY...SOUTHERN NEVADA...AND NORTHWEST ARIZONA.
&&

.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.
&&

UPDATE...ADAIR
PREV DISCUSSION...PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER










000
FXUS65 KVEF 291043
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
343 AM PDT TUE JUL 29 2014

.SYNOPSIS...MONSOON MOISTURE WILL REMAIN IN PLACE MAINLY ACROSS
NORTHWEST ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO
ISOLATED THUNDERSTORMS MAINLY CONFINED TO THE HIGHER TERRAIN.
TEMPERATURES WILL RETURN TO NEAR NORMAL WEDNESDAY AND THURSDAY.
THERE STILL LOOKS TO BE AN UPSWING IN THUNDERSTORMS OVER THE WEEKEND.
&&

.SHORT TERM...THROUGH THURSDAY NIGHT...
WATER VAPOR SHOWS A SHORTWAVE LIFTING NORTHEAST INTO SOUTHWEST UTAH
WITH AN ANTICYCLONIC CIRCULATION OVER NORTHWEST NEVADA EARLY THIS
MORNING. AN AREA OF CONVERGENCE/DEFORMATION BETWEEN THESE TWO
SYSTEMS IS ROUGHLY ALIGNED FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. RADAR/SURFACE OBSERVATIONS SHOWING LIGHT
RAIN SHOWERS IN THIS BOUNDARY FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. SINCE MIDNIGHT, TWO SITES IN ESMERALDA
COUNTY (GOLDFIELD AND DYER) HAVE RECORDED AROUND A TENTH OF AN INCH.
OTHERWISE, RAINFALL TOTALS HAVE AMOUNTED TO ONLY A FEW HUNDREDTHS.

THE BOUNDARY IS PROGGED TO GRADUALLY WEAKEN THROUGHOUT THE DAY BUT
WE ARE STILL EXPECTING ANOTHER DAY OF TERRAIN DRIVEN CONVECTION.
REGIONAL INTEGRATED PRECIPITABLE WATER VALUES HAVE CHANGED LITTLE
FROM YESTERDAY BUT THAT SHOULD CHANGE THROUGHOUT THE DAY AS SOME
DRIER AIR MOVES IN FROM THE SOUTHWEST. SINCE WE ARE NOT LOOKING AT
THE AREAL COVERAGE OF STORMS COMPARED TO YESTERDAY WILL NOT BE GOING
WITH ANY WATCH. THAT SAID, LOCALLY HEAVY RAIN WOULD BE THE PRIMARY
CONCERN WITH ANY THUNDERSTORM. NAM THE PREFERRED MODEL CONTINUES TO
ADVERTISE SLOW DRYING LEADING TO A GRADUAL DECREASE IN TERRAIN
DRIVEN THUNDERSTORM COVERAGE WEDNESDAY AND THURSDAY.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...SCATTERED SHOWERS AND THUNDERSTORMS WILL
BE CONFINED MAINLY TO THE SURROUNDING MOUNTAINS THIS AFTERNOON AND
EVENING. ONCE DEVELOPED STORMS WILL LIKELY IMPACT ALL THE CORRIDORS
AT SOME POINT. WINDS WILL FAVOR SOUTHERLY OVERNIGHT BEFORE BECOMING
LIGHT AND VARIABLE. SOUTHERLY WINDS WILL RETURN BY LATE AFTERNOON
WITH THE POTENTIAL OF OUTFLOW WIND AFFECTING ALL LAS VEGAS VALLEY
TERMINALS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...RAIN SHOWERS WILL PERSIST FROM NORTHERN INYO COUNTY
THROUGH SOUTH CENTRAL NEVADA INTO THE MORNING. TYPICAL SOUTHERLY
WINDS WITH A FEW GUSTS ARE EXPECTED THIS AFTERNOON. ISOLATED TO
SCATTERED THUNDERSTORMS ARE ONCE AGAIN POSSIBLE ACROSS INYO
COUNTY...SOUTHERN NEVADA...AND NORTHWEST ARIZONA.
&&

.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/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER







000
FXUS65 KVEF 291043
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
343 AM PDT TUE JUL 29 2014

.SYNOPSIS...MONSOON MOISTURE WILL REMAIN IN PLACE MAINLY ACROSS
NORTHWEST ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO
ISOLATED THUNDERSTORMS MAINLY CONFINED TO THE HIGHER TERRAIN.
TEMPERATURES WILL RETURN TO NEAR NORMAL WEDNESDAY AND THURSDAY.
THERE STILL LOOKS TO BE AN UPSWING IN THUNDERSTORMS OVER THE WEEKEND.
&&

.SHORT TERM...THROUGH THURSDAY NIGHT...
WATER VAPOR SHOWS A SHORTWAVE LIFTING NORTHEAST INTO SOUTHWEST UTAH
WITH AN ANTICYCLONIC CIRCULATION OVER NORTHWEST NEVADA EARLY THIS
MORNING. AN AREA OF CONVERGENCE/DEFORMATION BETWEEN THESE TWO
SYSTEMS IS ROUGHLY ALIGNED FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. RADAR/SURFACE OBSERVATIONS SHOWING LIGHT
RAIN SHOWERS IN THIS BOUNDARY FROM NORTHERN INYO COUNTY EAST THROUGH
NORTHERN LINCOLN COUNTY. SINCE MIDNIGHT, TWO SITES IN ESMERALDA
COUNTY (GOLDFIELD AND DYER) HAVE RECORDED AROUND A TENTH OF AN INCH.
OTHERWISE, RAINFALL TOTALS HAVE AMOUNTED TO ONLY A FEW HUNDREDTHS.

THE BOUNDARY IS PROGGED TO GRADUALLY WEAKEN THROUGHOUT THE DAY BUT
WE ARE STILL EXPECTING ANOTHER DAY OF TERRAIN DRIVEN CONVECTION.
REGIONAL INTEGRATED PRECIPITABLE WATER VALUES HAVE CHANGED LITTLE
FROM YESTERDAY BUT THAT SHOULD CHANGE THROUGHOUT THE DAY AS SOME
DRIER AIR MOVES IN FROM THE SOUTHWEST. SINCE WE ARE NOT LOOKING AT
THE AREAL COVERAGE OF STORMS COMPARED TO YESTERDAY WILL NOT BE GOING
WITH ANY WATCH. THAT SAID, LOCALLY HEAVY RAIN WOULD BE THE PRIMARY
CONCERN WITH ANY THUNDERSTORM. NAM THE PREFERRED MODEL CONTINUES TO
ADVERTISE SLOW DRYING LEADING TO A GRADUAL DECREASE IN TERRAIN
DRIVEN THUNDERSTORM COVERAGE WEDNESDAY AND THURSDAY.

.LONG TERM...FRIDAY THROUGH TUESDAY.

FRIDAY NOW LOOKS LIKE IT MAY BE THE LEAST ACTIVE DAY OF THE WEEK
ACROSS OUR AREA FOR SHOWERS AND THUNDERSTORMS AS THE FLOW ALOFT
REMAINS FROM THE SOUTHWEST AND DRIER AIR CONTINUES TO WORK EAST
ACROSS THE AREA. INSTABILITY REMAINS THE BEST ACROSS THE FAR
NORTHERN CWFA AND EASTERN MOHAVE COUNTY AND THAT IS WHERE WE
CONTINUED TO CONFINE A SLIGHT CHANCE FOR AFTERNOON AND EVENING
STORMS TO WITH HEATING AND TERRAIN DRIVING ACTIVITY ALONG WITH ANY
BOUNDARIES THAT FORM. OTHERWISE EXPECT NEAR SEASONABLE TEMPS WITH
DRY CONDITIONS.

JUST IN TIME FOR THE WEEKEND THINGS LOOK TO GET INTERESTING ONCE
AGAIN AS THE FOCUS TURNS TO AN INVERTED TROUGH OR SOME SORT OF
VORTICITY MAXIMUM OR LOBE FLOATING NORTHWEST AROUND THE RIDGE AXIS
ALOFT CENTERED NEAR THE FOUR CORNERS. THE 00Z OPERATIONAL RUNS OF
THE GFS, ECMWF AND GEM NOW SEEM TO BE SLOWER IN BRINGING THIS
FEATURE UP AND DELAY IT MORE UNTIL SATURDAY AFTERNOON INTO SATURDAY
NIGHT. HOWEVER, AN INFLUX OF MOISTURE IS PROGGED TO EJECT NORTH
FRIDAY NIGHT AND THIS SHOULD SET THIS STAGE FOR AN UPTICK IN SHOWER
AND THUNDERSTORM ACTIVITY ON SATURDAY, POSSIBLY STARTING IN THE
MORNING. AT THIS POINT, IT WOULD APPEAR THE EASTERN HALF OF THE AREA
WOULD BE THE MOST ACTIVE AS THE BETTER MOISTURE GETS INTO THESE
AREAS FIRST. THEN BY SATURDAY NIGHT INTO SUNDAY AS THE INVERTED
TROUGH OR VORTICITY MAXIMUM OR LOBE MOVES NORTH ACROSS OUR AREA
THINGS COULD GET EVEN MORE INTERESTING WITH THE POTENTIAL FOR
SHOWERS AND THUNDERSTORMS EVEN AT NIGHT AS THE PRESENCE OF THIS
FEATURE AS WELL AS BETTER 0-6 KM BULK SHEAR VALUES COULD ALSO
SUPPORT MORE ORGANIZED OR STRONGER CONVECTIVE ACTIVITY ON SUNDAY.
PWATS ARE PROGGED TO BE NEAR 1.50 INCH ACROSS THE SOUTHEAST CWFA
WHICH WILL MEAN THE ATMOSPHERE WILL HAVE PLENTY OF JUICE TO UNLOAD
HEAVY RAINFALL ALL WEEKEND IN STRONGER STORMS. THUS AN INCREASED
THREAT FOR FLASH FLOODING WILL EXIST. THE ONE THING IN THIS
SCENARIOS THAT IS A TOUGH CALL EVEN SHORTER IN TO THE EVENT IS HOW
MUCH CLOUD COVER WILL BE AROUND AS THIS WOULD LIMIT HEATING AND
COULD RESULT IN MORE OF A SHOWERS AND LOW GRADE THUNDERSTORM EVENT.
TEMPS SHOULD BE SEVERAL DEGREES BELOW NORMAL ALTHOUGH ANY GAIN IN
THE COMFORT FACTOR DEPARTMENT WILL BE OFFSET BY INCREASED HUMIDITY.

SUNDAY NIGHT INTO MONDAY, I WENT AHEAD AND BUMPED UP POPS SLIGHTLY
AS IT SEEMS MODELS ARE NOW SLOWER WITH DRYING ACROSS THE AREA IN THE
WAKE OF THE EJECTING FEATURE. DRIER AIR SHOULD CONTINUE TO SPREAD IN
FROM THE WEST ON TUESDAY. ACTIVITY THESE DAYS SHOULD BE MORE TERRAIN
AND BOUNDARY DRIVEN AND THUS I KEPT POPS GREATEST OVER THE HIGHER
TERRAIN ESPECIALLY IN THE NORTHERN AND EASTERN CWFA. TEMPS SHOULD
TREND CLOSER TO NORMAL AS SUNSHINE SHOULD BE MORE GENEROUS.
&&

.AVIATION...FOR MCCARRAN...SCATTERED SHOWERS AND THUNDERSTORMS WILL
BE CONFINED MAINLY TO THE SURROUNDING MOUNTAINS THIS AFTERNOON AND
EVENING. ONCE DEVELOPED STORMS WILL LIKELY IMPACT ALL THE CORRIDORS
AT SOME POINT. WINDS WILL FAVOR SOUTHERLY OVERNIGHT BEFORE BECOMING
LIGHT AND VARIABLE. SOUTHERLY WINDS WILL RETURN BY LATE AFTERNOON
WITH THE POTENTIAL OF OUTFLOW WIND AFFECTING ALL LAS VEGAS VALLEY
TERMINALS.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...RAIN SHOWERS WILL PERSIST FROM NORTHERN INYO COUNTY
THROUGH SOUTH CENTRAL NEVADA INTO THE MORNING. TYPICAL SOUTHERLY
WINDS WITH A FEW GUSTS ARE EXPECTED THIS AFTERNOON. ISOLATED TO
SCATTERED THUNDERSTORMS ARE ONCE AGAIN POSSIBLE ACROSS INYO
COUNTY...SOUTHERN NEVADA...AND NORTHWEST ARIZONA.
&&

.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/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER






000
FXUS65 KVEF 290448
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
948 PM PDT MON JUL 28 2014

.SYNOPSIS...THUNDERSTORM STORM COVERAGE WILL DECREASE TUESDAY AND
WEDNESDAY AS UPPER LEVEL DISTURBANCES LIFT AWAY TO THE NORTH.
MONSOON MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS NORTHWEST
ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO ISOLATED TO
SCATTERED THUNDERSTORMS EACH DAY.
&&

.UPDATE...
WENT AHEAD AND LET THE FLASH FLOOD WATCH GO AT 9 PM PDT...AS
THUNDERSTORM COVERAGE IS WANING AND THE ATMOSPHERE IS STABILIZING TO
THE POINT WHERE WIDESPREAD HEAVY RAIN PRODUCING STORMS ARE NO LONGER
EXPECTED. WE STILL HAVE TWO CIRCULATIONS SPINNING ACROSS THE
FORECAST AREA...THOUGH. ONE ACROSS ESMERALDA AND NORTHERN INYO
COUNTIES AND THE OTHER IS OVER SOUTHERN NEVADA. GUIDANCE HAS BEEN
FAIRLY CONSISTENT THE LAST FEW DAYS LIFTING THESE FEATURES TO OUR
NORTH OVERNIGHT. BOTH OF THESE WILL KEEP SOME SHOWERS AND A FEW
ISOLATED THUNDERSTORMS GOING OVERNIGHT...BUT ACTIVITY WILL LIFT
NORTH. RAINFALL RATES WILL ALSO BE MUCH LOWER WITH ANY OVERNIGHT
CONVECTION THAN WHAT WE EXPERIENCED THIS AFTERNOON AND EARLY
EVENING. ADDITIONALLY...CELLS SHOULD HAVE SOME MOVEMENT WITHOUT MUCH
/IF ANY/ TRAINING.
&&

.AVIATION...FOR MCCARRAN...SHOWERS AND A FEW THUNDERSTORMS WILL
IMPACT THE BEATTY...MORMON MESA...AND PEACH SPRINGS CORRIDORS
OVERNIGHT. THESE SAME CORRIDORS WILL BE IMPACTED AGAIN TUESDAY.
WINDS WILL FAVOR SOUTHERLY OVERNIGHT BEFORE BECOMING LIGHT AND
VARIABLE. SOUTHERLY WINDS WILL RETURN BY LATE TUESDAY AFTERNOON.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHOWERS AND A FEW THUNDERSTORMS WILL PERSIST OVER
NORTHERN INYO COUNTY...SOUTH CENTRAL NEVADA...AND NORTHWEST ARIZONA
OVERNIGHT. TYPICAL SOUTHERLY WINDS WITH A FEW GUSTS ARE EXPECTED
TUESDAY AFTERNOON. ISOLATED TO SCATTERED THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE ACROSS INYO COUNTY...SOUTH CENTRAL NEVADA...AND
NORTHWEST ARIZONA.
&&

.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.
&&

.PREVIOUS DISCUSSION...
304 PM PDT MON JUL 28 2014

.SHORT TERM...THROUGH WEDNESDAY NIGHT...NO SIGNIFICANT CHANGES WERE
MADE TO THE GENERAL FORECAST DURING THE PERIOD. THUNDERSTORMS WERE
DEVELOPING ABOUT AS DEPICTED BY THE 12Z HIGH RES MODELS...PRIMARILY
ALONG AND NORTH OF AN ARC EXTENDING FROM NORTHERN SAN BERNARDINO
ACROSS CLARK AND CENTRAL MOHAVE COUNTIES. ISOLATED STORMS WERE
DEVELOPING OVER SOUTHERN SAN BERNARDINO AND MOHAVE COUNTIES.
SATELLITE LOOPS SHOWED EMBEDDED LARGE UPPER LEVEL CIRCULATIONS
ENTRAINED IN SOUTHERLY FLOW LIFTING ACROSS THE FORECAST AREA FROM
SOUTHEAST CALIFORNIA INTO SOUTHERN NEVADA. CONVECTION WILL CONTINUE
ACROSS THE AFOREMENTIONED AREAS THROUGH LATE AFTERNOON AND EARLY
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED
OVERNIGHT ACROSS NORTHERN INYO COUNTY AND SOUTH CENTRAL NEVADA AS
THE DISTURBANCES SLOWLY LIFT NORTHWARD. WILL KEEP THE FLASH FLOOD
WATCH IN EFFECT UNTIL 9 PM FOR ALL ZONES. THE LATEST NAM AND GFS
SOLUTIONS CONTINUE TO INDICATE A DRYING TREND WITH LIGHT WESTERLY
FLOW DEVELOPING ACROSS SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA
BEHIND THE DISTURBANCES LIFTING TO THE NORTHEAST. THIS SHOULD LEAD
TO DECREASING THUNDERSTORM COVERAGE BUT SUFFICIENT MOISTURE AND
INSTABILITY WILL REMAIN THROUGH MID WEEK FOR ISOLATED TO SCATTERED
THUNDERSTORM COVERAGE EACH DAY.

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

$$

UPDATE/AVIATION...PADDOCK
SHORT TERM...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER








000
FXUS65 KVEF 290448
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
948 PM PDT MON JUL 28 2014

.SYNOPSIS...THUNDERSTORM STORM COVERAGE WILL DECREASE TUESDAY AND
WEDNESDAY AS UPPER LEVEL DISTURBANCES LIFT AWAY TO THE NORTH.
MONSOON MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS NORTHWEST
ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO ISOLATED TO
SCATTERED THUNDERSTORMS EACH DAY.
&&

.UPDATE...
WENT AHEAD AND LET THE FLASH FLOOD WATCH GO AT 9 PM PDT...AS
THUNDERSTORM COVERAGE IS WANING AND THE ATMOSPHERE IS STABILIZING TO
THE POINT WHERE WIDESPREAD HEAVY RAIN PRODUCING STORMS ARE NO LONGER
EXPECTED. WE STILL HAVE TWO CIRCULATIONS SPINNING ACROSS THE
FORECAST AREA...THOUGH. ONE ACROSS ESMERALDA AND NORTHERN INYO
COUNTIES AND THE OTHER IS OVER SOUTHERN NEVADA. GUIDANCE HAS BEEN
FAIRLY CONSISTENT THE LAST FEW DAYS LIFTING THESE FEATURES TO OUR
NORTH OVERNIGHT. BOTH OF THESE WILL KEEP SOME SHOWERS AND A FEW
ISOLATED THUNDERSTORMS GOING OVERNIGHT...BUT ACTIVITY WILL LIFT
NORTH. RAINFALL RATES WILL ALSO BE MUCH LOWER WITH ANY OVERNIGHT
CONVECTION THAN WHAT WE EXPERIENCED THIS AFTERNOON AND EARLY
EVENING. ADDITIONALLY...CELLS SHOULD HAVE SOME MOVEMENT WITHOUT MUCH
/IF ANY/ TRAINING.
&&

.AVIATION...FOR MCCARRAN...SHOWERS AND A FEW THUNDERSTORMS WILL
IMPACT THE BEATTY...MORMON MESA...AND PEACH SPRINGS CORRIDORS
OVERNIGHT. THESE SAME CORRIDORS WILL BE IMPACTED AGAIN TUESDAY.
WINDS WILL FAVOR SOUTHERLY OVERNIGHT BEFORE BECOMING LIGHT AND
VARIABLE. SOUTHERLY WINDS WILL RETURN BY LATE TUESDAY AFTERNOON.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...SHOWERS AND A FEW THUNDERSTORMS WILL PERSIST OVER
NORTHERN INYO COUNTY...SOUTH CENTRAL NEVADA...AND NORTHWEST ARIZONA
OVERNIGHT. TYPICAL SOUTHERLY WINDS WITH A FEW GUSTS ARE EXPECTED
TUESDAY AFTERNOON. ISOLATED TO SCATTERED THUNDERSTORMS ARE ONCE
AGAIN POSSIBLE ACROSS INYO COUNTY...SOUTH CENTRAL NEVADA...AND
NORTHWEST ARIZONA.
&&

.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.
&&

.PREVIOUS DISCUSSION...
304 PM PDT MON JUL 28 2014

.SHORT TERM...THROUGH WEDNESDAY NIGHT...NO SIGNIFICANT CHANGES WERE
MADE TO THE GENERAL FORECAST DURING THE PERIOD. THUNDERSTORMS WERE
DEVELOPING ABOUT AS DEPICTED BY THE 12Z HIGH RES MODELS...PRIMARILY
ALONG AND NORTH OF AN ARC EXTENDING FROM NORTHERN SAN BERNARDINO
ACROSS CLARK AND CENTRAL MOHAVE COUNTIES. ISOLATED STORMS WERE
DEVELOPING OVER SOUTHERN SAN BERNARDINO AND MOHAVE COUNTIES.
SATELLITE LOOPS SHOWED EMBEDDED LARGE UPPER LEVEL CIRCULATIONS
ENTRAINED IN SOUTHERLY FLOW LIFTING ACROSS THE FORECAST AREA FROM
SOUTHEAST CALIFORNIA INTO SOUTHERN NEVADA. CONVECTION WILL CONTINUE
ACROSS THE AFOREMENTIONED AREAS THROUGH LATE AFTERNOON AND EARLY
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED
OVERNIGHT ACROSS NORTHERN INYO COUNTY AND SOUTH CENTRAL NEVADA AS
THE DISTURBANCES SLOWLY LIFT NORTHWARD. WILL KEEP THE FLASH FLOOD
WATCH IN EFFECT UNTIL 9 PM FOR ALL ZONES. THE LATEST NAM AND GFS
SOLUTIONS CONTINUE TO INDICATE A DRYING TREND WITH LIGHT WESTERLY
FLOW DEVELOPING ACROSS SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA
BEHIND THE DISTURBANCES LIFTING TO THE NORTHEAST. THIS SHOULD LEAD
TO DECREASING THUNDERSTORM COVERAGE BUT SUFFICIENT MOISTURE AND
INSTABILITY WILL REMAIN THROUGH MID WEEK FOR ISOLATED TO SCATTERED
THUNDERSTORM COVERAGE EACH DAY.

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

$$

UPDATE/AVIATION...PADDOCK
SHORT TERM...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER







000
FXUS65 KVEF 282204
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
304 PM PDT MON JUL 28 2014

.SYNOPSIS...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL
OCCUR THROUGH THIS EVENING ACROSS THE REGION. STORM COVERAGE WILL
DECREASE TUESDAY AND WEDNESDAY AS UPPER LEVEL DISTURBANCES LIFT AWAY
TO THE NORTH. MONSOON MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS
NORTHWEST ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO
ISOLATED TO SCATTERED THUNDERSTORMS EACH DAY.
&&

.SHORT TERM...THROUGH WEDNESDAY NIGHT...NO SIGNIFICANT CHANGES WERE
MADE TO THE GENERAL FORECAST DURING THE PERIOD. THUNDERSTORMS WERE
DEVELOPING ABOUT AS DEPICTED BY THE 12Z HIGH RES MODELS...PRIMARILY
ALONG AND NORTH OF AN ARC EXTENDING FROM NORTHERN SAN BERNARDINO
ACROSS CLARK AND CENTRAL MOHAVE COUNTIES. ISOLATED STORMS WERE
DEVELOPING OVER SOUTHERN SAN BERNARDINO AND MOHAVE COUNTIES.
SATELLITE LOOPS SHOWED EMBEDDED LARGE UPPER LEVEL CIRCULATIONS
ENTRAINED IN SOUTHERLY FLOW LIFTING ACROSS THE FORECAST AREA FROM
SOUTHEAST CALIFORNIA INTO SOUTHERN NEVADA. CONVECTION WILL CONTINUE
ACROSS THE AFOREMENTIONED AREAS THROUGH LATE AFTERNOON AND EARLY
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED
OVERNIGHT ACROSS NORTHERN INYO COUNTY AND SOUTH CENTRAL NEVADA AS
THE DISTURBANCES SLOWLY LIFT NORTHWARD. WILL KEEP THE FLASH FLOOD
WATCH IN EFFECT UNTIL 9 PM FOR ALL ZONES. THE LATEST NAM AND GFS
SOLUTIONS CONTINUE TO INDICATE A DRYING TREND WITH LIGHT WESTERLY
FLOW DEVELOPING ACROSS SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA
BEHIND THE DISTURBANCES LIFTING TO THE NORTHEAST. THIS SHOULD LEAD
TO DECREASING THUNDERSTORM COVERAGE BUT SUFFICIENT MOISTURE AND
INSTABILITY WILL REMAIN THROUGH MID WEEK FOR ISOLATED TO SCATTERED
THUNDERSTORM COVERAGE EACH DAY.
&&

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS IMPACTING THE TERMINAL AREA
THROUGH LATE AFTERNOON ARE EXPECTED TO MOVE OFF TO THE NORTH DURING
BY EARLY EVENING. OUTFLOW WINDS OVER 15 KTS FROM NEARBY STORMS
THROUGH THE EVENING MAY CAUSE CONFIGURATION ADJUSTMENTS. SCATTERED
THUNDERSTORMS IMPACT ALL APPROACH CORRIDORS THROUGH EARLY EVENING
THEN THE BEATTY AND MORMON MESA CORRIDORS OVERNIGHT.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED AREAWIDE
THROUGH THIS EVENING. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN
AND LOWER CEILINGS IN AND NEAR THUNDERSTORMS. STORM COVERAGE WILL
DIMINISH SOUTH I-15 THIS EVENING BUT PERSIST OVER INYO COUNTY AND
SOUTH CENTRAL NEVADA OVERNIGHT.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED
LATER TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&

$$

SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER










000
FXUS65 KVEF 282204
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
304 PM PDT MON JUL 28 2014

.SYNOPSIS...SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS WILL
OCCUR THROUGH THIS EVENING ACROSS THE REGION. STORM COVERAGE WILL
DECREASE TUESDAY AND WEDNESDAY AS UPPER LEVEL DISTURBANCES LIFT AWAY
TO THE NORTH. MONSOON MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS
NORTHWEST ARIZONA AND SOUTHERN NEVADA THROUGH THE WEEK LEADING TO
ISOLATED TO SCATTERED THUNDERSTORMS EACH DAY.
&&

.SHORT TERM...THROUGH WEDNESDAY NIGHT...NO SIGNIFICANT CHANGES WERE
MADE TO THE GENERAL FORECAST DURING THE PERIOD. THUNDERSTORMS WERE
DEVELOPING ABOUT AS DEPICTED BY THE 12Z HIGH RES MODELS...PRIMARILY
ALONG AND NORTH OF AN ARC EXTENDING FROM NORTHERN SAN BERNARDINO
ACROSS CLARK AND CENTRAL MOHAVE COUNTIES. ISOLATED STORMS WERE
DEVELOPING OVER SOUTHERN SAN BERNARDINO AND MOHAVE COUNTIES.
SATELLITE LOOPS SHOWED EMBEDDED LARGE UPPER LEVEL CIRCULATIONS
ENTRAINED IN SOUTHERLY FLOW LIFTING ACROSS THE FORECAST AREA FROM
SOUTHEAST CALIFORNIA INTO SOUTHERN NEVADA. CONVECTION WILL CONTINUE
ACROSS THE AFOREMENTIONED AREAS THROUGH LATE AFTERNOON AND EARLY
EVENING. SCATTERED SHOWERS AND THUNDERSTORMS CAN BE EXPECTED
OVERNIGHT ACROSS NORTHERN INYO COUNTY AND SOUTH CENTRAL NEVADA AS
THE DISTURBANCES SLOWLY LIFT NORTHWARD. WILL KEEP THE FLASH FLOOD
WATCH IN EFFECT UNTIL 9 PM FOR ALL ZONES. THE LATEST NAM AND GFS
SOLUTIONS CONTINUE TO INDICATE A DRYING TREND WITH LIGHT WESTERLY
FLOW DEVELOPING ACROSS SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA
BEHIND THE DISTURBANCES LIFTING TO THE NORTHEAST. THIS SHOULD LEAD
TO DECREASING THUNDERSTORM COVERAGE BUT SUFFICIENT MOISTURE AND
INSTABILITY WILL REMAIN THROUGH MID WEEK FOR ISOLATED TO SCATTERED
THUNDERSTORM COVERAGE EACH DAY.
&&

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS IMPACTING THE TERMINAL AREA
THROUGH LATE AFTERNOON ARE EXPECTED TO MOVE OFF TO THE NORTH DURING
BY EARLY EVENING. OUTFLOW WINDS OVER 15 KTS FROM NEARBY STORMS
THROUGH THE EVENING MAY CAUSE CONFIGURATION ADJUSTMENTS. SCATTERED
THUNDERSTORMS IMPACT ALL APPROACH CORRIDORS THROUGH EARLY EVENING
THEN THE BEATTY AND MORMON MESA CORRIDORS OVERNIGHT.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED AREAWIDE
THROUGH THIS EVENING. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN
AND LOWER CEILINGS IN AND NEAR THUNDERSTORMS. STORM COVERAGE WILL
DIMINISH SOUTH I-15 THIS EVENING BUT PERSIST OVER INYO COUNTY AND
SOUTH CENTRAL NEVADA OVERNIGHT.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED
LATER TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&

$$

SHORT TERM/AVIATION...ADAIR
LONG TERM...STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER











000
FXUS65 KVEF 281710
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1010 AM PDT MON JUL 28 2014

.SYNOPSIS...SCATTERED THUNDERSTORMS WITH HEAVY RAIN POSSIBLE TODAY.
HEAVY RAIN WILL LIKELY LEAD TO AREAS OF FLASH FLOODING. MONSOON
MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS NORTHWEST ARIZONA AND
SOUTHERN NEVADA THROUGH THE WEEK LEADING TO A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&

.UPDATE...NO SIGNIFICANT CHANGES PLANNED TO THE FORECAST AS THE
LATEST OBSERVATIONS AND GUIDANCE SUPPORT THE TRENDS DETAILED IN THE
PREVIOUS DISCUSSION. HIGH RES MODELS INDICATE THE MOST ACTIVE AREA
FOR ORGANIZED CONVECTION WILL BE CLARK COUNTY NORTHWARD AS A LARGE
CIRCULATION CURRENTLY LIFTING OUT OF NORTHERN BAJA MOVES OVER
SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA BY THIS AFTERNOON. THE
FLASH FLOOD WATCH FOR THE ENTIRE AREA IS WARRANTED BUT WE MAY SEE
LESS CONVECTIVE ACTIVITY OVER SOUTHERN SAN BERNARDINO AND MOHAVE
COUNTIES.
&&

.PREV DISCUSSION...
405 AM PDT MON JUL 28 2014

.SHORT TERM...THROUGH WEDNESDAY NIGHT...
AT THIS EARLY HOUR, SCATTERED THUNDERSTORMS ARE OCCURRING OVER PARTS
OF LAS VEGAS EXTENDING EAST INTO THE LAKE MEAD NATL RECREATION AREA
AND NORTH INTO LINCOLN COUNTY. ONE CELL NEAR NELLIS AFB HAS DUMPED
AROUND A QUARTER OF AN INCH SINCE 3 AM.

DECIDED TO GO WITH A FLASH FLOOD WATCH FOR THE ENTIRE FORECAST AREA
FROM 9 AM - 9 PM TODAY AS ALL THE INGREDIENTS SEEM TO BE COMING
TOGETHER. THE TRIGGERS WILL BE RESIDUAL MCV OVER THE WESTERN MOJAVE
DESERT WHICH IS PROGGED TO SLOWLY LIFT NORTH THROUGH CENTRAL
CALIFORNIA. THIS FEATURE WILL HELP ORGANIZE DEVELOPMENT IN INYO,
INCLUDING THE EAST SLOPES OF THE SOUTHERN SIERRA. SECONDARY FEATURE
IS ONE THAT THE MODELS HAVE BEEN CONSISTENTLY SHOWING FOR TWO DAYS
NOW. THAT IS THE SHORTWAVE/PV ANOMALY OVER NORTHERN BAJA THAT IS
PROGGED TO MOVE NORTH UP THE COLORADO RIVER VALLEY HELPING ORGANIZE
STORMS OVER NORTHWEST ARIZONA, SOUTHERN NEVADA AND EASTERN SAN
BERNARDINO COUNTY. NAM BUFR SOUNDINGS INDICATE SIMILAR PRECIPITABLE
WATER TO YESTERDAY, OR ABOUT 150-200 PERCENT OF NORMAL WITH LIFTED
INDICES -2 TO -4. AFTER TODAY, MODELS STILL SHOW A SHIFT NORTH IN
ACTIVITY TUESDAY WITH A SHIFT BACK SOUTH WITH A LEAST A SLIGHT
CHANCE OF STORMS FOR THE HIGHER TERRAIN OF THE MOJAVE DESERT
WEDNESDAY.

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS GENERALLY NORTH/NORTHEAST
OF THE LAS VEGAS VALLEY TERMINALS THIS MORNING. MORMON MESA/BEATTY
CORRIDORS MOST IMPACTED. ADDITIONAL DEVELOPMENT EXPECTED THROUGH THE
REMINDER OF THE AFTERNOON/EVENING WILL IMPACT ALL CORRIDORS.
THUNDERSTORMS WILL BRING ERRATIC GUSTY WINDS...HEAVY RAIN AND LOWER
CIGS AT TIMES.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED AREAWIDE
TODAY. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN AND LOWER
CEILINGS IN AND NEAR THUNDERSTORMS.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED
LATER TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&

$$

UPDATE...ADAIR
PREV DISCUSSION...PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER







000
FXUS65 KVEF 281710
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1010 AM PDT MON JUL 28 2014

.SYNOPSIS...SCATTERED THUNDERSTORMS WITH HEAVY RAIN POSSIBLE TODAY.
HEAVY RAIN WILL LIKELY LEAD TO AREAS OF FLASH FLOODING. MONSOON
MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS NORTHWEST ARIZONA AND
SOUTHERN NEVADA THROUGH THE WEEK LEADING TO A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&

.UPDATE...NO SIGNIFICANT CHANGES PLANNED TO THE FORECAST AS THE
LATEST OBSERVATIONS AND GUIDANCE SUPPORT THE TRENDS DETAILED IN THE
PREVIOUS DISCUSSION. HIGH RES MODELS INDICATE THE MOST ACTIVE AREA
FOR ORGANIZED CONVECTION WILL BE CLARK COUNTY NORTHWARD AS A LARGE
CIRCULATION CURRENTLY LIFTING OUT OF NORTHERN BAJA MOVES OVER
SOUTHEAST CALIFORNIA AND SOUTHERN NEVADA BY THIS AFTERNOON. THE
FLASH FLOOD WATCH FOR THE ENTIRE AREA IS WARRANTED BUT WE MAY SEE
LESS CONVECTIVE ACTIVITY OVER SOUTHERN SAN BERNARDINO AND MOHAVE
COUNTIES.
&&

.PREV DISCUSSION...
405 AM PDT MON JUL 28 2014

.SHORT TERM...THROUGH WEDNESDAY NIGHT...
AT THIS EARLY HOUR, SCATTERED THUNDERSTORMS ARE OCCURRING OVER PARTS
OF LAS VEGAS EXTENDING EAST INTO THE LAKE MEAD NATL RECREATION AREA
AND NORTH INTO LINCOLN COUNTY. ONE CELL NEAR NELLIS AFB HAS DUMPED
AROUND A QUARTER OF AN INCH SINCE 3 AM.

DECIDED TO GO WITH A FLASH FLOOD WATCH FOR THE ENTIRE FORECAST AREA
FROM 9 AM - 9 PM TODAY AS ALL THE INGREDIENTS SEEM TO BE COMING
TOGETHER. THE TRIGGERS WILL BE RESIDUAL MCV OVER THE WESTERN MOJAVE
DESERT WHICH IS PROGGED TO SLOWLY LIFT NORTH THROUGH CENTRAL
CALIFORNIA. THIS FEATURE WILL HELP ORGANIZE DEVELOPMENT IN INYO,
INCLUDING THE EAST SLOPES OF THE SOUTHERN SIERRA. SECONDARY FEATURE
IS ONE THAT THE MODELS HAVE BEEN CONSISTENTLY SHOWING FOR TWO DAYS
NOW. THAT IS THE SHORTWAVE/PV ANOMALY OVER NORTHERN BAJA THAT IS
PROGGED TO MOVE NORTH UP THE COLORADO RIVER VALLEY HELPING ORGANIZE
STORMS OVER NORTHWEST ARIZONA, SOUTHERN NEVADA AND EASTERN SAN
BERNARDINO COUNTY. NAM BUFR SOUNDINGS INDICATE SIMILAR PRECIPITABLE
WATER TO YESTERDAY, OR ABOUT 150-200 PERCENT OF NORMAL WITH LIFTED
INDICES -2 TO -4. AFTER TODAY, MODELS STILL SHOW A SHIFT NORTH IN
ACTIVITY TUESDAY WITH A SHIFT BACK SOUTH WITH A LEAST A SLIGHT
CHANCE OF STORMS FOR THE HIGHER TERRAIN OF THE MOJAVE DESERT
WEDNESDAY.

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS GENERALLY NORTH/NORTHEAST
OF THE LAS VEGAS VALLEY TERMINALS THIS MORNING. MORMON MESA/BEATTY
CORRIDORS MOST IMPACTED. ADDITIONAL DEVELOPMENT EXPECTED THROUGH THE
REMINDER OF THE AFTERNOON/EVENING WILL IMPACT ALL CORRIDORS.
THUNDERSTORMS WILL BRING ERRATIC GUSTY WINDS...HEAVY RAIN AND LOWER
CIGS AT TIMES.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED AREAWIDE
TODAY. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN AND LOWER
CEILINGS IN AND NEAR THUNDERSTORMS.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED
LATER TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&

$$

UPDATE...ADAIR
PREV DISCUSSION...PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER








000
FXUS65 KVEF 281105
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
405 AM PDT MON JUL 28 2014

.SYNOPSIS...SCATTERED THUNDERSTORMS WITH HEAVY RAIN POSSIBLE TODAY.
HEAVY RAIN WILL LIKELY LEAD TO AREAS OF FLASH FLOODING. MONSOON
MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS NORTHWEST ARIZONA AND
SOUTHERN NEVADA THROUGH THE WEEK LEADING TO A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&

.SHORT TERM...THROUGH WEDNESDAY NIGHT...
AT THIS EARLY HOUR, SCATTERED THUNDERSTORMS ARE OCCURRING OVER PARTS
OF LAS VEGAS EXTENDING EAST INTO THE LAKE MEAD NATL RECREATION AREA
AND NORTH INTO LINCOLN COUNTY. ONE CELL NEAR NELLIS AFB HAS DUMPED
AROUND A QUARTER OF AN INCH SINCE 3 AM.

DECIDED TO GO WITH A FLASH FLOOD WATCH FOR THE ENTIRE FORECAST AREA
FROM 9 AM - 9 PM TODAY AS ALL THE INGREDIENTS SEEM TO BE COMING
TOGETHER. THE TRIGGERS WILL BE RESIDUAL MCV OVER THE WESTERN MOJAVE
DESERT WHICH IS PROGGED TO SLOWLY LIFT NORTH THROUGH CENTRAL
CALIFORNIA. THIS FEATURE WILL HELP ORGANIZE DEVELOPMENT IN INYO,
INCLUDING THE EAST SLOPES OF THE SOUTHERN SIERRA. SECONDARY FEATURE
IS ONE THAT THE MODELS HAVE BEEN CONSISTENTLY SHOWING FOR TWO DAYS
NOW. THAT IS THE SHORTWAVE/PV ANOMALY OVER NORTHERN BAJA THAT IS
PROGGED TO MOVE NORTH UP THE COLORADO RIVER VALLEY HELPING ORGANIZE
STORMS OVER NORTHWEST ARIZONA, SOUTHERN NEVADA AND EASTERN SAN
BERNARDINO COUNTY. NAM BUFR SOUNDINGS INDICATE SIMILAR PRECIPITABLE
WATER TO YESTERDAY, OR ABOUT 150-200 PERCENT OF NORMAL WITH LIFTED
INDICES -2 TO -4. AFTER TODAY, MODELS STILL SHOW A SHIFT NORTH IN
ACTIVITY TUESDAY WITH A SHIFT BACK SOUTH WITH A LEAST A SLIGHT
CHANCE OF STORMS FOR THE HIGHER TERRAIN OF THE MOJAVE DESERT
WEDNESDAY.

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS GENERALLY NORTH/NORTHEAST
OF THE LAS VEGAS VALLEY TERMINALS THIS MORNING. MORMON MESA/BEATTY
CORRIDORS MOST IMPACTED. ADDITIONAL DEVELOPMENT EXPECTED THROUGH THE
REMINDER OF THE AFTERNOON/EVENING WILL IMPACT ALL CORRIDORS.
THUNDERSTORMS WILL BRING ERRATIC GUSTY WINDS...HEAVY RAIN AND LOWER
CIGS AT TIMES.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED AREAWIDE
TODAY. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN AND LOWER
CEILINGS IN AND NEAR THUNDERSTORMS.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED
LATER TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&

$$

PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER







000
FXUS65 KVEF 281105
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
405 AM PDT MON JUL 28 2014

.SYNOPSIS...SCATTERED THUNDERSTORMS WITH HEAVY RAIN POSSIBLE TODAY.
HEAVY RAIN WILL LIKELY LEAD TO AREAS OF FLASH FLOODING. MONSOON
MOISTURE WILL REMAIN IN PLACE MOSTLY ACROSS NORTHWEST ARIZONA AND
SOUTHERN NEVADA THROUGH THE WEEK LEADING TO A CHANCE OF SHOWERS AND
THUNDERSTORMS.
&&

.SHORT TERM...THROUGH WEDNESDAY NIGHT...
AT THIS EARLY HOUR, SCATTERED THUNDERSTORMS ARE OCCURRING OVER PARTS
OF LAS VEGAS EXTENDING EAST INTO THE LAKE MEAD NATL RECREATION AREA
AND NORTH INTO LINCOLN COUNTY. ONE CELL NEAR NELLIS AFB HAS DUMPED
AROUND A QUARTER OF AN INCH SINCE 3 AM.

DECIDED TO GO WITH A FLASH FLOOD WATCH FOR THE ENTIRE FORECAST AREA
FROM 9 AM - 9 PM TODAY AS ALL THE INGREDIENTS SEEM TO BE COMING
TOGETHER. THE TRIGGERS WILL BE RESIDUAL MCV OVER THE WESTERN MOJAVE
DESERT WHICH IS PROGGED TO SLOWLY LIFT NORTH THROUGH CENTRAL
CALIFORNIA. THIS FEATURE WILL HELP ORGANIZE DEVELOPMENT IN INYO,
INCLUDING THE EAST SLOPES OF THE SOUTHERN SIERRA. SECONDARY FEATURE
IS ONE THAT THE MODELS HAVE BEEN CONSISTENTLY SHOWING FOR TWO DAYS
NOW. THAT IS THE SHORTWAVE/PV ANOMALY OVER NORTHERN BAJA THAT IS
PROGGED TO MOVE NORTH UP THE COLORADO RIVER VALLEY HELPING ORGANIZE
STORMS OVER NORTHWEST ARIZONA, SOUTHERN NEVADA AND EASTERN SAN
BERNARDINO COUNTY. NAM BUFR SOUNDINGS INDICATE SIMILAR PRECIPITABLE
WATER TO YESTERDAY, OR ABOUT 150-200 PERCENT OF NORMAL WITH LIFTED
INDICES -2 TO -4. AFTER TODAY, MODELS STILL SHOW A SHIFT NORTH IN
ACTIVITY TUESDAY WITH A SHIFT BACK SOUTH WITH A LEAST A SLIGHT
CHANCE OF STORMS FOR THE HIGHER TERRAIN OF THE MOJAVE DESERT
WEDNESDAY.

.LONG TERM...THURSDAY THROUGH MONDAY.

THURSDAY BASICALLY LOOKS LIKE AN EXTENSION OF WHAT MAY BE AROUND ON
WEDNESDAY. A RIDGE ALOFT REMAINS CENTERED OVER EASTERN
ARIZONA/WESTERN NEW MEXICO KEEPING THE AREA IN A SOUTHWEST FLOW.
LI`S ARE SHOWN TO BE FAIRLY STABLE PER THE GFS AND WHATEVER
INSTABILITY AND MID-LEVEL MOISTURE THAT WOULD BE SUFFICIENT TO
TRIGGER CONVECTION REMAINS CONFINED TO THE FAR NORTHERN CWFA AND FAR
EASTERN MOHAVE COUNTY. WE HAVE KEPT IN A SLIGHT CHANCE OF AFTERNOON
AND EVENING THUNDERSTORMS THERE. OTHERWISE EXPECT DRY CONDITIONS
WITH TEMPS AT OR A LITTLE ABOVE NORMAL. AT THIS POINT, FRIDAY DOES
NOT APPEAR TO BE TOO DIFFERENT FROM THURSDAY WITH THE GREATEST RISK
FOR AFTERNOON AND EVENING THUNDERSTORMS IN THE SAME AREAS. OTHERWISE
IT SHOULD ONCE AGAIN BE DRY WITH TEMPS AT OR ABOVE NORMAL.

THE REAL PERIOD OF INTEREST IS FROM FRIDAY NIGHT THROUGH SUNDAY
NIGHT AS WHAT APPEARS TO BE EITHER AN INVERTED TROUGH OR JUST SOME
SORT OF VORTICITY MAX OR LOBE FLOATS AROUND THE RIDGE AND HEADS
ACROSS THE LOWER COLORADO RIVER VALLEY ON FRIDAY NIGHT OR SATURDAY
MORNING BEFORE EVENTUALLY HEADING NORTH. THE TIMING ON THIS FEATURE
VARIES BETWEEN THE ECMWF, GFS AND GEM BUT THEY ALL SHOW IT. GIVEN
THE REASONABLE MODEL AGREEMENT OF THIS TRIGGER FEATURE AS WELL AS
THE INCREASE IN MOISTURE SHOWN TO PUSH IN WITH PWATS OFF THE GFS
PROGGED TO EXCEED A JUICY 1.50 INCHES AND SUFFICIENT INSTABILITY AND
CAPE, ESPECIALLY BY SUNDAY, I HAVE GONE AHEAD AND INCREASED POPS
ACROSS THE AREA. THE MAIN CONCERN WILL BE HOW MUCH CLOUD COVER
ULTIMATELY COMES UP, AS THIS COULD LIMIT HEATING AND JUST RESULT IN
MORE SHOWERS AND LOW-GRADE THUNDERSTORMS. ON THE OTHER HAND, THE
MOISTURE WILL BE PLENTIFUL, AND IF MORE POTENT STORMS GET GOING, THE
RISK FOR FLASH FLOODING WILL BE GREATER. THE PRESENCE OF THIS
INVERTED TROUGH OR VORTICITY MAX OR LOBE WILL COULD ALSO FAVOR
CONVECTION DEVELOPING AT NIGHT. I DID GO AHEAD AND ALSO RAISE
DEWPOINTS AND LOWERED MAX TEMPS A COUPLE OF DEGREES ESPECIALLY ON
SUNDAY.

THE GFS IS SLOWER TO BRING IN THIS FEATURE AND THUS EJECT IT
COMPARED TO THE ECMWF. AS A RESULT, WE MAINTAINED THE PROSPECTS FOR
THUNDERSTORMS OVER MORE OF THE AREA ON MONDAY IN CASE IT IS SLOWER
TO MOVE OUT. HOWEVER, WE SHOULD SEE A DOWNWARD TREND STARTING ON
MONDAY IN THE AMOUNT OF THUNDERSTORMS AROUND AND WITH MORE HEATING
SEE TEMPS GET BACK CLOSER TO NORMAL.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS GENERALLY NORTH/NORTHEAST
OF THE LAS VEGAS VALLEY TERMINALS THIS MORNING. MORMON MESA/BEATTY
CORRIDORS MOST IMPACTED. ADDITIONAL DEVELOPMENT EXPECTED THROUGH THE
REMINDER OF THE AFTERNOON/EVENING WILL IMPACT ALL CORRIDORS.
THUNDERSTORMS WILL BRING ERRATIC GUSTY WINDS...HEAVY RAIN AND LOWER
CIGS AT TIMES.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS EXPECTED AREAWIDE
TODAY. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN AND LOWER
CEILINGS IN AND NEAR THUNDERSTORMS.
&&

.SPOTTER INFORMATION STATEMENT...SPOTTER ACTIVATION MAY BE NEEDED
LATER TODAY. SPOTTERS ARE ENCOURAGED TO REPORT ANY SIGNIFICANT
WEATHER CONDITIONS ACCORDING TO STANDARD OPERATING PROCEDURES.
&&

$$

PIERCE/STACHELSKI

FOR MORE FORECAST INFORMATION...SEE US ON OUR WEBPAGE:

HTTP://WEATHER.GOV/LASVEGAS OR FOLLOW US ON FACEBOOK AND TWITTER






000
FXUS65 KVEF 280446
AFDVEF

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
946 PM PDT SUN JUL 27 2014

.SYNOPSIS...MONSOON MOISTURE WILL BRING A CHANCE OF THUNDERSTORMS TO
MUCH OF THE AREA THROUGH THE FIRST HALF OF THE WEEK. TEMPERATURES
WILL GENERALLY BE NEAR NORMAL.
&&

.UPDATE...
A BIT MORE ACTIVE THIS EVENING WHEN COMPARED TO YESTERDAY. WE HAD
SOME LOCALIZED FLOODING ACROSS THE AREA AND EVEN A DUST STORM FROM
DOLAN SPRINGS TO KINGMAN AZ ALONG HIGHWAY 93. MCCARRAN AIRPORT
MEASURED 0.01 INCHES OF RAIN SO I GUESS WE CAN START A NEW DRY
STREAK. A MESOSCALE CONVECTIVE VORTEX CONTINUES TO SLOWLY TRACK
ACROSS SAN BERNARDINO COUNTY AT THIS HOUR. EXPECT SHOWERS AND SOME
THUNDERSTORMS TO CONTINUE ACROSS OUR WESTERN FORECAST AREA FOR MUCH
OF THE OVERNIGHT HOURS WITH THAT FEATURE HANGING AROUND. WE MAY SEE
A LULL AT SOME POINT...BUT HIRES MODELS INDICATE ACTIVITY TO PICK UP
ACROSS OUR WEST IN THE PRE-DAWN HOURS. WE CONTINUE TO WATCH A
WEAKENING STORM COMPLEX EDGE INTO MOHAVE COUNTY FROM NORTHERN AZ.
THIS WILL LIKELY BRING SOME SHOWERS AND PERHAPS A FEW RUMBLES OF
THUNDER TO PORTIONS OF MOHAVE COUNTY TONIGHT. ADDITIONALLY...THERE
IS A PV ANOMALY WORKING NORTHWARD FROM BAJA. THIS WILL BE OUR MAIN
PLAYER FOR TOMORROW BUT WILL ALSO KEEP LARGE-SCALE FORCING AROUND
THE REGION FOR A CONTINUATION OF SOME CONVECTION OVERNIGHT.
&&

.AVIATION...FOR MCCARRAN...THUNDERSTORMS NEAR THE TERMINAL WILL
BRING ERRATIC GUSTY WINDS AT TIMES MONDAY EVENING. ISOLATED TO
SCATTERED THUNDERSTORMS ARE EXPECTED IN ALL FOUR CORRIDORS AS WELL.

FOR THE REST OF SOUTHERN NEVADA...NORTHWEST ARIZONA...AND SOUTHEAST
CALIFORNIA...ISOLATED TO SCATTERED THUNDERSTORMS ARE EXPECTED
AREAWIDE MONDAY. EXPECT ERRATIC GUSTY WINDS...VERY HEAVY RAIN AND
LOW CEILINGS IN AND NEAR THUNDERSTORMS.
&&

.PREVIOUS DISCUSSION...
242 PM PDT SUN JUL 27 2014

.SHORT TERM...THROUGH TUESDAY NIGHT...WILL BE BRIEF AS THUNDERSTORMS
ARE FIRING NORTH OF A LINE FROM MOUNTAIN PASS CA TO THE WEST RIM OF
THE GRAND CANYON AS OF 2 PM. HIGH RESOLUTION MODELS HAVE BEEN DOING
QUITE WELL WITH THUNDERSTORM COVERAGE THE PAST FEW DAYS...AND THEY
SUGGEST MORE COVERAGE FOR TOMORROW. LOTS OF MOISTURE IN PLACE SO THE
MAIN THREAT WILL CONTINUE TO BE FLASH FLOODING. MADE NO CHANGES TO
TUESDAY AS THIS EVENING AND TOMORROW WERE THE MAIN CONCERNS.

.LONG TERM...WEDNESDAY THROUGH SUNDAY...AN UPPER LEVEL HIGH PRESSURE
RIDGE WILL REMAIN ANCHORED IN PLACE OVER THE SW US FOR MOST OF THE
PERIOD. THIS WILL KEEP THE AREA RELATIVELY MOIST AND ACTIVE WITH
AFTERNOON CONVECTION FOR MOST OF THE WEEK. ALTHOUGH MONDAY IS LIKELY
TO BE THE MOST ACTIVE DAY. POPS AND CHANCES FOR THUNDERSTORMS WILL
BE SOMEWHAT LOWER THROUGH THE WEEK AS THE SOUTHERLY FLOW IS SOMEWHAT
WEAKER. AFTERNOON SHOWER AND THUNDERSTORMS WILL BE MOST LIKELY TO
OCCUR OVER MOHAVE COUNTY AND HIGHER TERRAIN IN CLARK AND EASTERN SAN
BERNARDINO COUNTY.

AN AFOREMENTIONED UPPER LEVEL TROF WILL SINK SOUTH OVER THE PACIFIC
COAST NEXT WEEKEND. THIS MAY BRING ABOUT SOME STRONGER MID-LEVEL
FORCING FOR CONVECTIVE ACTIVITY. WE WILL NEED TO SEE HOW THINGS
DEVELOP OVER THE COURSE OF THE WEEK.
&&

.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.
&&

$$

UPDATE...PADDOCK
PREV DISCUSSION...MORGAN/LERICOS

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