Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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000
FXUS66 KMTR 281026
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
326 AM PDT TUE JUL 28 2015

...VERY WARM TO HOT INLAND TEMPERATURES EXPECTED TODAY THROUGH
THURSDAY OF THIS WEEK....

.SYNOPSIS...A SIGNIFICANT WARM-UP IS FORECAST TO CONTINUE ACROSS
INLAND AREAS THROUGH MIDWEEK...AND MORE MODEST TEMPERATURE
INCREASES CLOSER TO THE COAST AS STRONG HIGH PRESSURE BUILDS OVER
THE REGION. TEMPERATURES COOL SLIGHTLY LATE IN THE WEEK ALONG
WITH INCREASED MONSOON MOISTURE APPROACHING FROM THE SOUTH.

&&

.DISCUSSION...AS OF 3:15 AM PDT TUESDAY...COMPLETELY CLEAR START
TO THE DAY TODAY WILL BOTH SATELLITE AND SURFACE OBS INDICATING NO
CLOUD COVER ACROSS OUR CWA OR OVER THE WATERS. CURRENT SURFACE
ANALYSIS SHOWS NORTH TO SOUTH GRADIENT AT 4 MB OR DOUBLE OF WEST
TO EAST. THAT COMBINED WITH A MARINE LAYER SQUASHED TO AROUND 500
FEET HAS LEAD TO THE CLEAR START.

BIGGER PICTURE SYNOPTICALLY SHOWS A BUILDING RIDGE OF HIGH
PRESSURE TO OUR SOUTH THAT WILL ADVANCE THROUGH OUR CWA LATER
TODAY. AT THE SAME TIME 850 MB TEMPS WILL RISE AROUND 3C BY THIS
AFTERNOON COMPARED TO YESTERDAY. THIS WILL HELP TO PUSH HIGHS TO
ABOVE NORMAL LEVELS FOR ALMOST ALL LOCATIONS. INLAND HIGHS WILL
GENERALLY BE IN 90S TO LOWER 100S WHILE COASTAL SPOTS WILL SEE
LESS OF A WARM UP DUE TO AFTERNOON SEA BREEZES. HIGHS CLOSE TO THE
COAST WILL GENERALLY BE IN THE UPPER 60S TO AROUND 80S.

THE RIDGE WILL REMAIN THE DOMINATE WEATHER FEATURE THROUGH
THURSDAY AS 850 MB TEMPS INCREASE AN ADDITIONAL 2 TO 3C AND 500 MB
HEIGHTS INCREASE ANOTHER 2 TO 3 DM. THIS WILL LEAD TO TWO
ADDITIONAL DAYS OF VERY WARM TEMPERATURES INLAND WITH HIGHS AGAIN
EXPECTED TO GENERALLY BE IN THE 90S TO LOWER 100S. MODELS CONTINUE
TO FAVOR ONSHORE FLOW FOR BOTH AFTERNOONS WHICH WILL HELP TO
MODERATE THE HEATING.

WORTH NOTING THAT GUIDANCE THIS MORNING COMPARED TO THE PREVIOUS
TWO MORNINGS HAS SLIGHTLY BACKED OFF ON THE HEATING FOR THE WEEK
SUGGESTING THAT A HEAT ADVISORY IS NOT NECESSARY.
REGARDLESS...TEMPS WILL STILL BE QUITE WARM.

BY LATE THURSDAY SUBTROPICAL MOISTURE ROTATING AROUND THE RIDGE
OF HIGH PRESSURE WILL ADVANCE TOWARD OUR REGION. WHETHER OR NOT
ENOUGH OF IT MAKES IT TO OUR CWA ALONG WITH SIGNIFICANT
INSTABILITY REMAINS TO BE SEEN. 0Z GFS BRINGS SCATTERED SHOWERS
AND THUNDERSTORMS TO THE SOUTHERN QUARTER OF THE CWA FOR LATE
THURSDAY THROUGH FRIDAY NIGHT WHILE THE GFS AND NAVGEM KEEP ANY
SHOWER ACTIVITY TO THE SOUTH AND EAST. NAM SOLUTION BRINGS A FEW
SHOWERS TO SAN BENITO COUNTY ON FRIDAY. WENT WITH A SLIGHT CHANCE
FOR SHOWERS AND THUNDERSTORMS UNTIL BETTER AGREEMENT CAN BE
REACHED.

LONGER RANG OUTLOOK FOR THE WEEKEND THROUGH NEXT WEEK KEEPS SHOWER
ACTIVITY TO OUR EAST ALONG WITH HIGHS NEAR TO SLIGHTLY ABOVE
NORMAL.
&&

.AVIATION...AS OF 10:39 PM PDT MONDAY...CLEAR SKIES WILL PREVAIL
ACROSS THE REGION THROUGH THE FORECAST PERIOD AS A THERMAL TROUGH
REMAINS POSITIONED ALONG THE CALIFORNIA COAST. LIGHT OFFSHORE FLOW
IS EXPECTED THROUGH MIDWEEK AS THE THERMAL TROUGH SHIFT WEST. HIGH
CONFIDENCE.

VICINITY OF KSFO...VFR CONDITIONS WILL PREVAIL THROUGH THE FORECAST
PERIOD. LIGHT WINDS

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...VFR CONDITIONS WILL PREVAIL THROUGH
THE FORECAST PERIOD. LIGHT WINDS.

&&

.MARINE...AS OF 02:25 AM PDT TUESDAY...A THERMAL TROUGH SITUATED
OVER THE STATE WILL MAINTAIN GUSTY NORTHWEST WINDS THROUGH THIS
EVENING. THE GUSTY WINDS WILL PRODUCE LOCALLY STEEP WIND WAVES.
WINDS WILL DECREASE TONIGHT AND WEDNESDAY AS THE THERMAL TROUGH
SLIDES WEST...RELAXING THE SURFACE PRESSURE GRADIENT AND IMPROVING
SEA CONDITIONS.

&&

.CLIMATE...HERE ARE RECORD HIGHS FOR TUESDAY THROUGH THURSDAY
ACROSS OUR AREA ALONG WITH THE LAST YEAR THE RECORD WAS RECORDED.

SF BAY AREA..............7/28............7/29............7/30
 KENTFIELD..............98/1934........105/1954........105/1977
 SAN RAFAEL............104/1980........101/1977........102/1977
 NAPA..................107/1954........105/1954........103/1977
 SAN FRANCISCO..........84/1954.........83/1977.........85/1986
 SFO....................88/1954.........91/1977.........97/1977
 OAKLAND................76/1977.........98/1977.........95/1977
 OAKLAND AIRPORT........96/1954.........91/1977.........95/1977
 RICHMOND...............88/1954.........82/1967.........80/1993
 LIVERMORE.............106/1980........108/1954........107/1979
 MOUNTAIN VIEW..........93/1954.........93/1977.........97/1977
 SAN JOSE..............100/1954.........95/1977........102/1995
 GILROY................101/1995........102/1980........106/1977

MONTEREY BAY AREA........7/28...........7/29.............7/30
 MONTEREY...............85/1954........86/1977..........91/1977
 SANTA CRUZ.............92/1947........88/1964.........102/1977
 SALINAS................92/1954........95/1977..........86/1995
 SALINAS AIRPORT........84/1967........92/1977..........84/1977
 KING CITY..............99/1967.......105/1977.........106/1977

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...SCA...PT ARENA TO PIGEON PT 10-60 NM UNTIL 3 PM
             SCA...SF BAY FROM NOON

&&

$$

PUBLIC FORECAST: BELL
AVIATION: CW
MARINE: MM
CLIMATE: BELL/BENJAMIN

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