Damaging Winds in Nevada, September 4, 2007

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ELKO NV
200 AM PDT TUE SEP 4 2007

.SYNOPSIS...A COLD FRONT WILL MOVE THROUGH NORTHERN AND CENTRAL
NEVADA TODAY TRIGGERING SCATTERED SHOWERS AND THUNDERSTORMS THROUGH
WEDNESDAY. BREEZY CONDITIONS AND COOLER TEMPERATURES ARE ALSO
EXPECTED THROUGH THE MIDDLE OF THE WEEK BEFORE TEMPERATURES
START TO REBOUND BY NEXT WEEKEND. &&

.SHORT TERM...TUESDAY AND WEDNESDAY...CURRENT WATERVAPOR LOOP SHOWS
PACIFIC TROUGH APPROACHING THE OREGON COASTLINE AND SHOWING SIGNS OF
DIGGING SE INTO NRN CALIF AND SRN OREGON. CURRENT RADAR IMAGERY
SHOWS ISOLD TSTORMS AND WDLY SCT SHOWERS ALONG AND SOUTH OF HIGHWAY
50 ACROSS CTNRL NV. WILL LIKELY SEE THIS ACTIVITY CONTINUE THIS
MORNING ACROSS THAT AREA AS TROUGH AND 90 KT UPPERLEVEL JET
APPROACH THE AREA. WATERVAPOR LOOP ALSO SHOWING DRY SLOT PUSHING INTO
CNTRL CALIF AND WRN NV IN SOUTHWESTERLY FLOW...BELIEVE THIS FEATURE
WILL KEEP SHOWERS AND TSTORMS FURTHER EAST...MAINLY IN ELKO AND
WHITE PINE COUNTIES TODAY. KEPT POPS AROUND 45 PCT MAINLY ALONG AND
EAST OF HIGHWAY 93...AND THE CNTRL MOUNTAINS. MODELS ALL AGREE ON
WINDY CONDITIONS THIS AFTERNOON AHEAD OF THE MAIN COLD FRONT. WITH
500MB WINDS APPROACHING 55KTS...EXPECT SOME RATHER STRONG WIND
GUSTS AND BLOWING DUST THIS AFTERNOON IN AND NEAR THIS DRY SLOT.
ALSO...WITH CONSIDERABLE AMOUNT OF DRY AIR ALOFT AND SOME MIDLEVEL
SHEAR...EXPECT GUSTY WINDS WITH TSTORMS IN ERN NV.  ADDED BLDU AND
GUSTY TSTORM WINDS TO FORECAST ACROSS NORTH CNTRL...AND ERN NV
RESPECTIVELY. WOULD NOT BE SURPRISED IF ONE OR TWO OF THESE TSTORMS
REACH STRONG TO SEVERE LIMITS IN TERMS OF WIND GUSTS THIS AFTERNOON.

MODELS THEN SHOW UPPERLEVEL LOW STALLING OVER NE NV TONIGHT AND INTO
WEDNESDAY WITH SCT SHOWERS AND ISOLD TSTORMS CONTINUING MAINLY
ACROSS NE NV...BUT COULD REACH EAST CNTRL NV AS WELL AS SHORTWAVE
ENERGY ROTATES AROUND MAIN LOW. INCREASED POPS TONIGHT AND
WEDNESDAY...WITH SHOWERS POSSIBLY BECOMING HEAVY AT TIMES. A FEW OF
THE HIGHEST MOUNTAIN PEAKS ABOVE 10000 FEET MAY SEE THEIR FIRST FEW
SNOWFLAKES OF THE YEAR TONIGHT AS 700MB TEMPS DROP BELOW 4C. LOWERED
MAX TEMPS WEDNESDAY A FEW DEGS...PORTIONS OF NORTHEAST NV MAY
STRUGGLE TO REACH 70 DEGS FOR DAYTIME HIGHS...WITH MID TO UPPER 70S
EXPECTED ELSEWHERE. TT

.LONG TERM...WEDNESDAY NIGHT THROUGH MONDAY. MODELS CONTINUE TO BE
IN DECENT AGREEMENT EARLY IN PERIOD BUT DIVERGE BY LATE WEEKEND. FEW
CHANGES MADE TO EXTENDED PORTION OF FORECAST. DID INCREASE POPS
SLIGHTLY WED NIGHT AND ADDED SLIGHT CHANCE SHOWERS OVER NORTHEAST
CWA AS RESIDUAL MOISTURE FROM DEPARTING TROF MAY BE ENOUGH FOR SOME
SHOWERS...ESPECIALLY OVER HIGHER TERRAIN.

AT 00Z MON OPERATIONAL GFS MOST AMPLIFIED WITH 596DM HIGH NEAR 45N
150W AND DEEP TROF OVER NORTHERN CONUS. ECMWF AND GFS ENSEMBLES LESS
AMPLIFIED WITH ENSEMBLE MEAN KEEPING SOUTHERN PORTION OF POSITIVE
TILT TROF OVER CWA. EITHER WAY...PATTERN LOOKS MOSTLY DRY WITH
TEMPERATURES RUNNING NEAR- TO SLIGHTLY ABOVE NORMAL. ALSO MAINTAINED
LOW POPS BELOW 15 PERCENT OVER SOUTHERN CWA LATER IN EXTENDED PERIOD
WITH INCREASING MID-LEVEL MOISTURE A POSSIBILITY. SAVADEL
&&

.AVIATION...ISOLD THUNDERSTORMS CONTINUING OVERNIGHT ALONG ROUTE 406
WITH SCATTERED COVERAGE EXPECTED DURING THE DAY OVER ROUTES 383 AND
406. GUSTY WINDS ALSO EXPECTED ACROSS THE REGION WITH FRONTAL SYSTEM
MOVING ACROSS THE AREA AHEAD OF STRONG UPPER LEVEL TROUGH.
VISIBILITY MAY BE LOWERED AT TIMES DUE TO BLOWING DUST AND ASH
MAINLY ALONG ROUTE 404. UNSETTLED CONDITIONS WILL CONTINUE
THROUGH TUESDAY NIGHT ACROSS CENTRAL/NORTHERN NEVADA AND UTAH AS
MAIN TROUGH SWINGS THROUGH THE REGION. SAVADEL
&&

.FIRE WEATHER...KEPT RED FLAG GOING FOR TODAY MAINLY FOR GUSTY WINDS
AS COLD FRONT PUSHES THROUGH THE AREA. DAYTIME MIN RH/S WILL BE
QUESTIONABLE BUT SHOULD SEE A PERIOD OF NEAR 15% RH/S EARLY THIS
AFTERNOON. ZONES 454...451 AND 457 LOOK THE MOST LIKELY TO REACH
CRITERIA ATTM. OTHERWISE...COOLER TEMPS...HIGHER HUMIDITIES...AND
LIGHTER WINDS EXPECTED THROUGH THE END OF THE WEEK. &&

.LKN WATCHES/WARNINGS/ADVISORIES...

RED FLAG WARNING FOR ALL FWZ ZONES FROM 10 AM THIS MORNING UNTIL 7
PM THIS EVENING