Severe Thunderstorm Warning 11, NWS Las Vegas, NV

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
1010 AM PDT SAT AUG 14 2004

.SYNOPSIS...MOIST UNSTABLE AIR WILL CONTINUE TO SUPPORT SCATTERED
THUNDERSTORM DEVELOPMENT OVER THE SOUTHERN HALF OF THE DISTRICT
AGAIN TODAY AND TOMORROW. CLOUD COVER AND RELATIVELY HIGH HUMIDITY
WILL KEEP MAXIMUM TEMPERATURES SLIGHTLY BELOW NORMAL.
&&

.SHORT TERM...ELONGATED QUASI-STATIONARY TROUGH EXTENDS FROM
NORTHWEST SAN BERNARDINO COUNTY ESE TO SOUTHEAST ARIZONA. TWO
MID-LEVEL CIRCULATION CENTERS EVIDENT IN SATELLITE IMAGERY - ONE
VCNTY LAKE HAVASU AND THE OTHER N OF TUCSON. BOUNDARY LAYER HEATING
BEING INHIBITED SOMEWHAT BY CLOUD COVER BUT IT SHOULD THIN OUT AS WE
HEAD INTO AFTERNOON. COOL AIR ALOFT EMBEDDED IN TROUGH WILL ASSIST
IN DESTABILZATION OF AIR MASS AS WELL. MODEST LARGE SCALE FORCING
ASSOCIATED WITH THE HAVASU VORTEX COMBINED WITH DIFFERENTIAL HEATING
AND NUMEROUS REMNANT CONVECTIVE BOUNDARIES SHOULD BE SUFFICIENT TO
INITIATE STORMS THIS AFTERNOON. DRA SOUNDING AND LAS SOUNDER BOTH
DEPICTED ALMOST 1.5 OF PW. WEAK STEERING FLOW COUPLED WITH PRESENCE
OF THAT JUICY AIR WILL RESULT IN THREAT OF FLASH FLOODING WITH SOME
OF THE STORMS. WATCH IS IN EFFECT FOR PARTS OF CLARK...MOHAVE...AND
SAN BERNARDINO COUNTIES FROM NOON UNTIL 9 PM. LAS VEGAS RADAR IS OUT
OF COMMISSION BUT PART IS SCHEDULED TO ARRIVE TODAY SO WE HOPE TO
HAVE IT BACK IN SERVICE BEFORE THINGS GET TOO EXCITING.
&&

.LONG TERM...MODELS IN PRETTY GOOD AGREEMENT WITH OVERALL PATTERN
TUESDAY THROUGH FRIDAY. WEAK UPPER TROUGH EXITING THE REGION TO THE
EAST ON TUESDAY WITH A RIDGE OVER THE AREA WEDNESDAY FOLLOWED BY A
BIT OF A SOUTHWESTERLY FLOW THURSDAY AND FRIDAY. THIS SCENARIO WOULD
LEAD TO A GRADUAL DRYING AND WARMING OF THE AIRMASS OVER THE MOJAVE
DESERT AND SOUTHERN GREAT BASIN. LEFT CHANCE TO SLIGHT CHANCE POPS
OVER THE EASTERN AND FAR NORTHERN ZONES TUESDAY WITH MAINLY JUST THE
SAN BERNARDINO DESERTS AND SOUTHERN INYO COUNTY DRY. POPS LIMITED TO
JUST MOJAVE AND LINCOLN COUNTY ON WEDNESDAY WITH VIRTUALLY NO
THUNDERSTORMS IN THE FORECAST THURSDAY AND FRIDAY. WARMED TEMPS TO
AT OR JUST ABOVE NORMAL FOR THURSDAY AND FRIDAY WITH THE DRIER AIR.

&&

.AVIATION...TAF ADEQUATELY COVERS ALL SIGNIFICANT WEATHER EXPECTED
AT KLAS.
&&

.VEF WATCHES/WARNINGS/ADVISORIES...
.NV...FLOOD WATCH NOON TO 9 PM NVZ021-022.
.AZ...FLOOD WATCH NOON TO 9 PM AZZ002-003-036.
.CA...FLOOD WATCH NOON TO 9 PM CAZ028-029.
&&

RUNK/HARRISON

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAS VEGAS NV
1026 AM PDT SAT AUG 14 2004

AZZ001>003-036-CAZ026>029-NVZ014>022-151700-
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-
1026 AM PDT (1026 AM MST) SAT AUG 14 2004

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

.DAY ONE...TODAY.

SCATTERED THUNDERSTORMS WILL CONTINUE THIS AFTERNOON AND EVENING.
SOME STORMS ARE EXPECTED TO PRODUCE HEAVY RAIN AND FLASH FLOODING.
THE GREATEST THREAT WILL BE OVER SAN BERNARDINO...MOHAVE...AND
SOUTHERN CLARK COUNTIES.

.DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY.

SCATTERED AFTERNOON AND EVENING SHOWERS AND THUNDERSTORMS CAN BE
EXPECTED THROUGH AT LEAST WEDNESDAY WITH ISOLATED FLASH FLOODING AND
SEVERE STORMS POSSIBLE EACH DAY.

RUNK