Lightning Strike in California, September 19, 2004

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN JOAQUIN VALLEY - HANFORD CA
247 PM PDT SUN SEP 19 2004

.SHORT TERM...FOR THE CENTRAL CALIFORNIA INTERIOR...SATELLITE AND
RADAR LOOPS SHOW AN AREA OF LIGHT TO MODERATE SHOWERS OVER THE
NORTHERN PART OF THE HANFORD WARNING/FORECAST AREA...WITH A FEW
STATIONS REPORTING MEASURABLE AMOUNTS. /MERCED RECORDED 0.07 INCH
FROM A MODERATE SHOWER THAT MOVED OVER THE AIRPORT AROUND NOON./
THESE SHOWERS WILL CONTINUE TO MOVE ACROSS THE CENTRAL CALIFORNIA
INTERIOR THROUGH THIS EVENING...BUT WILL STAY MOSTLY NORTH OF
HANFORD AND VISALIA. EXPECT SHOWER ACTIVITY OVER THE SAN JOAQUIN
VALLEY TO WEAKEN AFTER SUNSET...AND HAVE DROPPED POPS TO ZERO AFTER
MIDNIGHT. HAVE KEPT POPS FOR THE SOUTHERN SIERRA NEVADA NORTH OF
KINGS CANYON OVERNIGHT DUE TO FAVORABLE OROGRAPHICS.

AT 20Z...TEMPERATURES IN THE SOUTHERN SIERRA NEVADA LOCALLY WERE IN
THE MID 30S AS LOW AS 6600 FEET /AT CRANE FLAT LOOK OUT/. THIS IS IN
AGREEMENT WITH MODEL ESTIMATES PLACING THE SNOW LEVEL TODAY BETWEEN
6000-6500 FEET. COULD SEE AT LEAST AN INCH OF NEW SNOW OVER THE
HIGHER ELEVATIONS OF THE SOUTHERN SIERRA NEVADA.

OTHER THAN THE PRECIPITATION...THE FORECAST CONCERN THIS AFTERNOON
IS TEMPERATURES TONIGHT AND MONDAY. TEMPERATURES IN THE CENTRAL AND
SOUTHERN SAN JOAQUIN VALLEY AT 21Z RANGED FROM 68-72 DEGREES...
EXCEPT FOR MERCED WHERE CLOUDS AND RAIN SUPPRESSED THE TEMPERATURE
TO ONLY 58 DEGREES. THIS MORNING/S LOW-LEVEL SOUNDINGS FOR FRESNO
AND BAKERSFIELD INDICATED A 7 DEGREE F COOLING FROM SATURDAY MORNING
FOR THE LOWEST LEVELS OF THE AIRMASS...AND FOR MUCH OF THE DAY WERE
DOWN 5-8 DEGREES F. FRESNO AND MADERA WERE ONLY DOWN 2 DEGREES AT
21Z...BUT THIS REFLECTED IN PART A LEVELLING OFF OF TEMPERATURES
DURING SATURDAY AFTERNOON. CENTRAL/SOUTH VALLEY HIGH TEMPERATURES
THIS AFTERNOON WILL LIKELY BE IN THE LOWER 70S...WITH FRESNO AND
BAKERSFIELD ONLY A COUPLE OF DEGREES ABOVE THEIR RECORD LOW MAXIMA
FOR TODAY OF 70 AND 69...RESPECTIVELY...BOTH SET IN 1989.

LOWS TONIGHT WILL BE DEPENDENT ON THE AMOUNT OF CLOUD COVER AND/OR
WIND MIXING...AS WELL AS HOW QUICKLY THE CLOUDS BEGIN TO DISSIPATE.
GIVEN THE UNCERTAINTY DUE TO THESE VARIABLES...HAVE KEPT MOST LOWS
SIMILAR TO THOSE IN THE PREVIOUS FORECAST PACKAGE. DID LOWER THE
VALLEY A FEW DEGREES IN LIGHT OF THIS MORNING/S READINGS.

THE PROFILERS AT CHOWCHILLA AND VISALIA INDICATE THAT THE POOL OF
MARINE AIR FILLING THE CENTRAL AND SOUTHERN SAN JOAQUIN VALLEY IS AT
LEAST 4000 FEET DEEP. WITH NO STRONG MECHANISM IN PLACE TO SCOUR
THIS COLD AIR POOL...TEMPERATURES AT THE LOWER LEVELS MONDAY WILL BE
SIMILAR TO...OR ONLY A DEGREE OR TWO WARMER THAN...TODAY. FOR THE
HIGHER ELEVATIONS...THE 12Z MODELS FORECAST 500-MB HEIGHTS TO JUMP
120 METERS /FROM 5580 TO 5700 METERS/ OVER CENTRAL CALIFORNIA BY 00Z
TUESDAY AS THE UPPER-LEVEL TROUGH MOVES EAST OF THE REGION. THIS
WILL BRING SYNOPTIC WARMING ABOVE THE MARINE AIR.

THE MODELS FORECAST ANOTHER 120-METER RISE IN 500-MB HEIGHTS TUESDAY
AS AN EAST PACIFIC RIDGE BUILDS INTO CALIFORNIA. AGAIN...THE HIGHER
ELEVATIONS WILL SEE THE STRONGEST WARMING AS THE PONDED MARINE AIR
WILL BE SLOW TO MODIFY AND MIX OUT. WARMING WILL CONTINUE WEDNESDAY
AS THE MODELS INCREASE 500-MB HEIGHTS BY YET ANOTHER 30 METERS. FALL
BEGINS AT 1630Z /0930 PDT/ ON WEDNESDAY...WITH FORECASTED HIGHS
STILL A FEW DEGREES BELOW NORMAL.

.LONG TERM...FOR THURSDAY THROUGH SUNDAY...NO BIG CHANGES EXPECTED
IN THE LONG TERM AS THE UPPER TROF PATTERN CONTINUES TO TRACK OUT OF
THE AREA BY MID WEEK. MODELS CONTINUE SHOWING GOOD OVERALL
CONSISTENCY IN BUILDING AN UPPER RIDGE OVER THE WEST COAST AROUND
WEDNESDAY AND THURSDAY. AN AREA OF WEAKNESS DOES DEVELOP OVER
NORTHERN CALIFORNIA AT THE START OF THE EXTENDED PERIOD...YET WILL
HAVE ONLY MINOR AFFECTS ON THE DISTRICT. FURTHERMORE...MEDIUM RANGE
MODELS DO DISAGREE WITH THE STRENGTH OF THE WEAKNESS AS THE CANADIAN
SHOWS ALMOST NO SIGNS OF THE DISTURBANCE. HOWEVER...FOR THE MODELS
THAT DO SHOW THE AREA OF WEAKNESS...THEY ALL DO INDICATE IT LIFTING
INTO THE UPPER INTERMOUNTAIN WEST HAS HEIGHTS CONTINUE RISING NEXT
WEEKEND. THEREFORE...WILL NOT MAKE ANY MAJOR CHANGES TO THE CURRENT
LONG TERM FORECAST VARIABLES AS CONDITIONS WILL REMAIN DRY WITH
TEMPERATURES RUNNING AT NEAR SEASONAL LEVELS.

&&

.HNX WATCHES/WARNINGS/ADVISORIES...NONE.

&&

SANGER/MOLINA