Heavy Snow in California, March 4 to 5, 2001

MOJAVE DESERT/SOUTHERN GREAT BASIN AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAS VEGAS NV
443 AM PST SUN MAR 4 2001

SYNOPSIS...MOISTURE WILL INCREASE TODAY AS ANOTHER WET PACIFIC
STORM SYSTEM APPROACHES THE CALIFORNIA COAST. VALLEY RAIN AND HIGH
ELEVATION SNOW WILL BECOME LIKELY OVER THE SIERRA TODAY. THIS SYSTEM
WILL THEN REMAIN OFF THE COAST THROUGH MONDAY WITH PERIODS OF RAIN
AND HIGH ELEVATION SNOW CONTINUING OVER THE SOUTHERN SIERRA AND
DESERTS OF CALIFORNIA. BECAUSE THIS STORM WILL REMAIN OFFSHORE...
ONLY OCCASIONAL LIGHT PRECIPITATION IS EXPECTED ACROSS NEVADA AND
NORTHWEST ARIZONA INTO MONDAY.

DISCUSSION...WIDESPREAD LIGHT TO MODERATE RAIN HAS SPREAD INTO THE
CENTRAL CALIFORNIA VALLEYS OVERNIGHT AHEAD OF THE TROUGH APPROACHING
THE WEST COAST. LOWER TO MID LEVEL CLOUDS WERE OBSERVED OVER BISHOP
AND TONOPAH WHILE HIGHER CLOUDS COVERED THE REMAINDER OF THE
FORECAST AREA. BASED ON SATELLITE TRENDS AND THE LATEST GUIDANCE...
THE IDEA OF BACKING OFF ON PRECIPITATION FOR THE SOUTHERN HALF OF
THE FORECAST AREA LOOKS GOOD AS THE LOW CENTER WILL REMAIN OFF THE
CENTRAL TO NORTHERN CALIFORNIA COAST THROUGH MONDAY. EACH SUCCESSIVE
MODEL RUN HAS SLOWED THIS SYSTEM. A SUBSTANTIAL AMOUNT OF MOISTURE
EXTENDING OFF SOUTHERN CALIFORNIA WILL BE DRAWN UP MAINLY TOWARD THE
SOUTHERN SIERRA DURING THE DAY AND SHOULD COMBINE WITH DYNAMICAL
FORCING AND FAVORABLE UPSLOPE FLOW FOR HEAVY SNOW OVER THE MOUNTAINS
OF INYO COUNTY TODAY THEN CONTINUE THROUGH MONDAY AND PROBABLY
TUESDAY FOR ANOTHER MAJOR SNOW EVENT. ONE DIFFERENCE FROM THE BIG
STORM A COUPLE WEEKS AGO IS SLIGHTLY HIGHER SNOW LEVELS...AROUND
6000 FEET.

ONE SIGNIFICANT THING TO WATCH TODAY IS STRONG WINDS OVER NORTHWEST
NYE COUNTY AS THE SURFACE LOW WINDS UP OFF THE NORTHERN CALIFORNIA
COAST WHILE THE 06Z ETA INDICATES 850 AND 700 MB WINDS ACROSS THE
RELATIVELY SMALL AREA OF 35 AND 55 KNOTS RESPECTIVELY. A TONOPAH TO
LOVELOCK CROSS SECTIONS SHOWS A GOOD POSSIBILITY OF STRONG DOWNSLOPE
WINDS IN THE VICINITY OF GABBS TODAY. ISSUED WIND ADVISORY
ACCORDINGLY.

SOME LIGHT PRECIP MAY MANAGE TO FALL OVER SOUTHERN NEVADA AND
NORTHWEST ARIZONA TONIGHT AND MONDAY...BUT IT NOW LOOKS LIKE TUESDAY
IS A BETTER BET FOR SIGNFICANT RAIN OR SNOW. ACCORDING TO THE LATEST
AVN...THE LOW CENTER IS STILL NORTHWEST OF POINT CONCEPTION BY 12Z
TUESDAY. ENERGY ROUNDING THE BASE OF THE TROUGH THEN SWINGS THROUGH
AND PROVIDES A GOOD SHOT FOR CENTRAL/SOUTHERN NEVADA AND NORTHWEST
ARIZONA DURING THE DAY. THE LOW MOVES TO NEAR THE FOUR CORNERS BY
WEDNESDAY AFTERNOON WHILE THE MRF SHOWS ANOTHER SYSTEM DROPPING DOWN
THE WEST COAST FOR AoNOTHER POSSIBLE ROUND IN THE EXTENDED PERIOD.

ADAIR

.LAS...A WINTER STORM WARNING AND WIND ADVISORY HAVE BEEN ISSUED.
PLEASE SEE THE LATEST RNOWSWLAS AND RNONPWLAS FOR DETAILS.