Severe Thunderstorm Warning 1, NWS Las Vegas, NV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
328 PM PDT FRI JUL 16 2004

.SYNOPSIS...A SLOW DECREASE IN MONSOON MOISTURE WILL OCCUR OVER THE
WEEKEND AND INTO EARLY NEXT WEEK. THIS DRYING WILL BE BROUGHT ON BY
A SOUTHWEST FLOW THAT WILL DEVELOP AS A LOW PRESSURE SYSTEM
APPROACHES THE WEST COAST. HOWEVER...ENOUGH RESIDUAL MOISTURE WILL
REMAIN THAT ONE CAN NOT RULE OUT ISOLATED TO SCATTERED THUNDERSTORMS
MAINLY OVER THE MOUNTAINS.
&&

.SHORT TERM...SIMILAR TO YESTERDAY STORMS ERUPTED OVER THE MOUNTAINS
OF CLARK COUNTY EARLY THEN HAVE SINCE MOVED NORTH INTO CENTRAL NYE
AND LINCOLN COUNTIES. STORMS SHOULD CONTINUE UP ACROSS SOUTH CENTRAL
NEVADA WELL INTO THE NIGHT AS MODELS KEEP A WEAK VORTICITY LOBE
CIRCULATING AROUND NORTHERN LINCOLN COUNTY. NEXT AREA OF CONCERN
DEALS WITH STORMS MOVING OUT OF YAVAPAI/COCONINO COUNTIES INTO
MOHAVE COUNTY. PRESENTLY...STRONGEST STORMS ARE OVER CENTRAL MOHAVE
COUNTY WITH MOVEMENT TOWARD THE NORTHWEST. STORM OUTFLOWS AND
PROPAGATION FROM ARIZONA STORMS SHOULD FIRE STORMS LATER THIS
AFTERNOON AND THROUGH THIS EVENING ACROSS THE LAKE MEAD NRA...CLARK
AND ERN SAN BERNARDINO COUNTY. HEAVY RAIN STILL A CONCERN FROM
STORMS BUT AGAIN BELIEF AREAS WILL BE LOCALIZED THAT FLASH FLOOD
WATCH NOT NEEDED. ETA MODEL SHOWING WEAK DISTURBANCE FROM DECAYING
COMPLEXES OVER SOUTH CENTRAL ARIZONA DESERTS THIS EVENING WILL BE
MOVING NORTHWARD INTO NORTHWEST ARIZONA OVERNIGHT SO POTENTIAL OF
NOCTURNAL STORMS POSSIBLE ACROSS MOHAVE COUNTY. MODELS IN AGREEMENT
THAT AS UPPER TROUGH APPROACHES THE PACIFIC NORTHWEST COAST LATE
SUNDAY AFTERNOON THAT UPPER FLOW BECOMES MORE SOUTHWESTERLY AND SLOW
DRYING WILL TAKE PLACE. ENOUGH RESIDUAL MOISTURE WILL STILL BE
AROUND THAT ISOLATED THUNDERSTORMS STILL POSSIBLE OVER AT LEAST THE
MOUNTAINS AND MOHAVE COUNTY SUNDAY AND MONDAY.
&&

.LONG TERM...SOME KNOCK DOWN OF RIDGE STILL EXPECTED FROM PAC
NORTHWEST TROUGH AND SOUTHWEST FLOW WILL DECREASE CONVECTION. IN
THE FAR EXTENDED...THURSDAY AND FRIDAY...THERE APPEARS TO BE TWO
CONTENDING ITEMS TO WATCH. THE GFS HAS A WEAK INVERTED TROUGH MOVING
WEST OVER MEXICO AND OVER THE GULF OF CA BY THURSDAY.  A PRECURSOR
TO ANOTHER MOISTURE SURGE? WHILE AT THE SAME TIME GFS ALSO CENTERS
UPPER HIGH OVER SOUTHERN NEVADA BY THEN. THIS WOULD RAISE
TEMPERATURES AND BRING ABOUT SOME SUBSIDENCE OVER MOST OF FORECAST
AREA. RIGHT NOW WILL GO WITH A MOSTLY DRY FORECAST WITH SILENT POPS
OVER TERRAIN OF MOHAVE AND LINCOLN COUNTIES.
&&

.AVIATION...THUNDERSTORMS ARE POSSIBLE FOR THE NEXT SEVERAL HOURS
OVER THE LAS VEGAS VALLEY. THEY ARE ALSO POSSIBLE AGAIN TOMORROW
AFTERNOON...HOWEVER PROBABILITIES FOR THIS WILL BE LESS THAN IN THE
LAST TWO DAYS.
&&

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

PIERCE/JACQUES

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAS VEGAS NV
1033 AM PDT FRI JUL 16 2004

AZZ001>003-036-CAZ026>029-NVZ014>022-170700-
DEATH VALLEY NATIONAL PARK-ESMERALDA AND CENTRAL NYE COUNTY-
LAKE HAVASU AND FORT MOJAVE-LAKE MEAD NATIONAL RECREATION AREA-
LAS VEGAS VALLEY-LINCOLN COUNTY-NORTHEAST CLARK COUNTY-
NORTHWEST DESERTS-NORTHWEST PLATEAU-
OWENS VALLEY AND ADJACENT EASTERN SIERRA SLOPES-
SAN BERNARDINO COUNTY DESERTS-SAN BERNARDINO COUNTY-
UPPER COLORADO RIVER VALLEY-SHEEP RANGE-SOUTHERN CLARK COUNTY-
SPRING MOUNTAINS-RED ROCK CANYON-
WESTERN CLARK AND SOUTHERN NYE COUNTY-
1033 AM PDT (1033 AM MST) FRI JUL 16 2004

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

.DAY ONE...TODAY.

THUNDERSTORMS WITH HEAVY RAIN WILL ONCE AGAIN OCCUR OVER THE
MOUNTAINS TODAY. THE STORMS WILL DECAY AS THEY MOVE OFF THE
MOUNTAINS AND INTO THE VALLEYS. STORMS OVER THE MOUNTAINS COULD
PRODUCE UP TO AN INCH OF RAIN AN HOUR WHILE SOME VALLEY
LOCATIONS MAY GET UP TO A HALF AN INCH OF RAIN.

.DAYS TWO THROUGH SEVEN...SATURDAY THROUGH FRIDAY.

THE PROBABILITY FOR WIDESPREAD HAZARDOUS WEATHER IS LOW.