Flood in Nevada, May 1 to 31, 2006

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE RENO NV
1005 PM PDT SUN APR 30 2006

.UPDATE...
MADE AN UPDATE TO THE POINT FORECASTS TO INCREASE THE TRUCKEE LOW
TEMPERATURES THE NEXT FEW DAYS.  DEW POINTS IN THE 30S TO LOW
40S...LACK OF SNOW COVER AND A LACK OF COLD AIR...DO NOT SUPPORT
MINIMUM TEMPERATURES IN THE LOW 20S AT TRUCKEE. AFTER COMPARING THE
LOW TEMPERATURES FROM THE TRUCKEE AIRPORT WITH ANOTHER OBSERVATION
SITE IN TRUCKEE...APPEARS THERE IS AN ERROR WITH THE LOW TEMPERATURE
READINGS FROM THE AIRPORT...SORRY FOR ANY INCONVENIENCE.  LOW
TEMPERATURES IN TRUCKEE SHOULD REMAIN BETWEEN 30 AND 35 DEGREES
THROUGH THIS WEEK.  BRONG

.PREVIOUS DISCUSSION ISSUED AT 230 PM PDT SUN APR 30...
.SHORT TERM...
FIRST COLD FRONT NOW WELL TO OUR SOUTH WITH SOME BUILDUPS FORMING
SOUTH OF HWY 50 WHERE WEAK NATURAL SURFACE CONVERGENCE AND WEAK
INSTABILITY REMAINS. THE ATMOSPHERE IS RELATIVELY DRY...SO OTHER
THAN A STRAY SHOWER OR TSTM PROBABLY WILL NOT SEE MUCH ACTIVITY EVEN
IN MONO OR MINERAL COUNTIES TODAY. CUMULUS CLOUDS FURTHER NORTH
SHOULD NOT PRODUCE ANY SHOWERS TODAY DUE TO LACK OF MOISTURE AND
INSTABILITY. ANOTHER WEAK FRONT WILL MOVE SOUTHEAST ACROSS NRN CA-NV
MONDAY AFTERNOON/EVENING AS A SHORT WAVE MOVES INTO THE PAC
NW...BRINGING SOME GUSTY NORTHWEST TO NORTHEAST WINDS ACROSS THE
AREA AND SLIGHTLY COOLER TEMPERATURES MONDAY AND TUESDAY. THE ONLY
POTENTIAL FOR SHOWER/TSTM ACTIVITY LOOKS TO BE OVER MONO/MINERAL
COUNTIES WHERE STRONGER NORTHERLY FLOW OVER THE NRN HALF OF OUR BEST
CONVERGENCE AND INSTABILITY REMAIN. COULD SEE SOME BUILDUPS FURTHER
NORTH AHEAD OF THE FRONT...BUT DUE TO LACK OF MOISTURE AND LACK OF
COOLER AIR ALOFT HAVE LEFT OUT OF THE FORECAST AT THIS TIME. A WEAK
UPPER LOW BEGINS TO FORM OVER NRN CA AND OFFSHORE ON TUESDAY AND
PUSHES WEAK PIECES OF ENERGY IN THE SIERRA AND MONO/MINERAL COUNTIES
TUESDAY AFTERNOON AND MORE SO ON WEDNESDAY. THEREFORE THE THREAT OF
CONVECTION CAN NEVER REALLY BE REMOVED WITH CONFIDENCE FROM SRN
ZONES THROUGH MID WEEK...ALTHOUGH THE BEST CHANCE FOR SHOWERS/TSTMS
IN THE SHORT TERM LOOKS TO BE ON WEDNESDAY WHEN SOUTH TO SOUTHEAST
FLOW AROUND LOW BEGINS TO DEVELOP. THEREFORE THE THREAT FOR TSTMS
WAS INCREASED BY WEDNESDAY AND SPREAD FURTHER NORTH INTO THE TAHOE
AREA. TEMPERATURES WILL CONTINUE TO REMAIN WELL ABOVE NORMAL THROUGH
THE WEEK. BENINATO

.LONG TERM...THURSDAY THROUGH SUNDAY...
UPPER LOW/TROF REMAINS OFF CENTRAL TO SOUTHERN CA COAST THURS AND
FRIDAY. ANOTHER SHORTWAVE MOVES INTO THE PACNW WHICH PUSHES THE
REMNANTS OF THIS UPPER LOW FURTHER SOUTH AND INCREASES WIND ACROSS
NORTHEAST CA AND NORTHERN NV SAT. BY LATE SAT AND EARLY SUNDAY THE
GFS BRUSHES THE TROUGH ACROSS NORTHERN NV WHICH WOULD PRODUCE
SLIGHTLY COOLER...BREEZY AND MORE STABLE CONDITIONS ACROSS NE CA AND
WESTERN NV. HOWEVER THE ECMWF KEEPS WEAK TROUGH OFF THE COAST INTO
SATURDAY. IF TIMING OF UPPER TROUGH MOVING ACROSS THE PACNW SAT IS
CLOSE TO THE 12Z GFS POSITION THIS WOULD BE FAVORABLE FOR SCT
THUNDERSTORMS TAHOE NORTH SIMILAR TO THOSE THAT WE HAD THIS PAST
SATURDAY. THERMAL TROUGH WEAK ON FRIDAY BUT SHOULD SHIFT TO WESTERN
NV AND THEN STRENGTHEN SOME SATURDAY. SPREAD A SLIGHT CHANCE OF
THUNDERSTORMS UP INTO LASSEN AND NORTHERN WASHOE COUNTIES FOR
SATURDAY WITH THE POSSIBILITY OF APPROACHING UPPER SHORTWAVE TO HELP
TRIGGER CONVECTION. ISOLATED DIURNAL THUNDERSTORMS WILL BE CONFINED
TO THE SIERRA CREST FROM TAHOE SOUTH THURS AND FRI. BETTER CHANCES
FOR THUNDERSTORMS SATURDAY ALONG SIERRA CREST AND NORTH OF
INTERSTATE 80... THEN JUST A POSSIBILITY OF ISOLATED CONVECTION FAR
SOUTH MONO/MINERAL COUNTIES IN MORE STABLE AIRMASS SUNDAY.
TEMPERATURES WILL REMAIN ABOVE NORMAL THROUGH THE PERIOD...WITH
UPPER 70S TO LOWER 80S IN WESTERN NV VALLEYS AND MAINLY 60S IN
MOUNTAIN VALLEYS. JAH

&&

.AVIATION...
VFR CONDITIONS THROUGH 00Z TUESDAY. ISOLATED AFTERNOON AND EVENING
THUNDERSTORMS ALONG SIERRA CREST 21Z-03Z SOUTH OF TVL. JAH

&&

.REV WATCHES/WARNINGS/ADVISORIES...
NV...FLOOD WARNING FOR THE HUMBOLDT RIVER IN PERSHING COUNTY UNTIL
     FURTHER NOTICE.
CA...NONE.
&&