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AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
500 PM PDT MON JUN 29 2015

.SYNOPSIS...A SIGNIFICANT WARMING TREND WILL CONTINUE ACROSS INLAND 
PORTIONS OF THE REGION THROUGH WEDNESDAY AS HIGH PRESSURE BUILDS
OVER THE WESTERN UNITED STATES. A SLIGHT COOLING TREND IS THEN
EXPECTED FOR THE LATTER HALF OF THE WEEK AS THE HIGH PRESSURE
WEAKENS AND RETREATS INLAND.

&&

.DISCUSSION...AS OF 02:54 PM PDT MONDAY...MANY INLAND LOCATIONS
ARE REPORTING TEMPERATURES IN THE 90S THIS AFTERNOON AS HIGH
PRESSURE OVER THE WESTERN CONUS CONTINUES TO BUILD TOWARD THE WEST
COAST. IN ADDITION...THE LOW LEVEL CLOUDS HAVE PUSHED WELL OFF OF
THE COAST THIS AFTERNOON DESPITE A MARINE LAYER AT AROUND 1200
FEET DEEP. HOWEVER...THE MARINE INFLUENCE AND WEAK ONSHORE FLOW
HAS HELD COASTAL TEMPERATURES GENERALLY IN THE 60S TO LOWER 70S.

THE INLAND WARMING TREND IS FORECAST TO CONTINUE THROUGH MIDWEEK
BEFORE REACHING A PEAK ON WEDNESDAY AFTERNOON. MOST INLAND AREAS
AWAY FROM THE COAST AND BAYS WILL SEE AFTERNOON TEMPERATURES
WARMING INTO THE 90S TO AS HIGH AS 108 IN THE WARMEST INLAND
VALLEYS AND HIGHER ELEVATIONS BOTH TUESDAY AND WEDNESDAY. COASTAL
LOCATIONS WILL LIKELY WARM INTO THE UPPER 60S TO 70S WITH A
PERSISTENT LIGHT ONSHORE FLOW. MEANWHILE...THE FORECAST MODELS
CONTINUE TO SHOW MID- LEVEL MOISTURE ADVECTION OVER THE STATE
THROUGH LATE WEEK AS MONSOONAL MOISTURE IS PULLED NORTHWARD ON THE
WEST SIDE OF THE MID/UPPER LEVEL HIGH. AT THIS TIME...THE BEST
CHANCES FOR CONVECTION WILL BE EAST OF OUR REGION WHERE GREATER
INSTABILITY AND MOISTURE IS EXPECTED. HOWEVER...THE LATEST GFS
MODEL INDICATES INCREASED POTENTIAL FOR CONVECTION OVER OUR REGION
THURSDAY AND FRIDAY. WILL CLOSELY MONITOR THE FORECAST MODELS AND
LOOK FOR RUN-TO-RUN CONSISTENCY BEFORE ADDING A MENTION OF
THUNDERSTORMS IN THE FORECAST.

OTHERWISE...MUCH OF THE REGION IS FORECAST TO EXPERIENCE DRY
WEATHER CONDITIONS THROUGH THE UPCOMING WEEKEND WITH HIGH PRESSURE
ALOFT. TEMPERATURES WILL BEGIN TO COOL REGION-WIDE LATE IN THE
WEEK AS THE MID/UPPER LEVEL RIDGE SLOWLY WEAKENS AND RETREATS
INLAND AWAY FROM THE COAST. WITH THE AFOREMENTIONED MID-LEVEL
MOISTURE ADVECTION THROUGH LATE WEEK...DO EXPECT AN INCREASE OF
MID/HIGH LEVEL CLOUDS OVER MUCH OF THE REGION. THIS TOO WILL AID
IN THE COOLING TREND...ESPECIALLY OVER THE INTERIOR.

&&

.AVIATION...AS OF 5:00 PM PDT MONDAY...STRATUS HAS CLEARED OUT
20-30 MILES OFFSHORE TODAY. MARINE LAYER BECOMING SHALLOWER BUT
BECOMING BETTER DEFINED AS THE AIRMASS ABOVE THE MARINE LAYER
WARMS UP. STRATUS EXPECTED TO SPREAD BACK INTO THE SFO AND MRY BAY
AREAS TONIGHT BUT AFTER THE AIRPORT EVENING RUSH.

VICINITY OF KSFO...MVFR AFTER 05Z POSSIBLY LATER. WEST WINDS 
TO 20 KT GUSTING TO 25 KT UNTIL 03Z. 

KSFO BRIDGE APPROACH...SAME AS SFO.
 
MONTEREY BAY AREA TERMINALS...CLOUDS HAVE CLEARED WELL AWAY FROM
THE BAY TODAY AND IFR CIGS SHOULD STAY OUT UNTIL AT LEAST 04Z.

&&

.MARINE...AS OF 02:54 PM PDT MONDAY...HIGH PRESSURE WILL CONTINUE
TO BRING MODERATE GUSTY NORTHWEST WINDS OVER THE COASTAL WATERS
THIS AFTERNOON AND THROUGH TONIGHT. WINDS DECREASE AFTER TUESDAY
AS A THERMAL TROUGH OVER THE INTERIOR SHIFTS TO THE COAST.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...SF BAY
             SCA...PIGEON PT TO PT PINOS 0-10 NM
             SCA...PT ARENA TO PT REYES 0-10 NM
             SCA...PT ARENA TO PIGEON PT 10-60 NM
             SCA...PT PINOS TO PT PIEDRAS BLANCAS 0-10 NM
             SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM

&&

$$

PUBLIC FORECAST: RGASS
AVIATION: W PI
MARINE: DRP


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