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

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS66 KMTR 301125
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
425 AM PDT TUE JUN 30 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. MOISTURE WILL ALSO MAKE ITS WAY
TOWARD OUR AREA FOR WEDNESDAY INTO THURSDAY WHICH COULD ALSO LEAD
TO A FEW SHOWERS AND THUNDERSTORMS.

&&

.DISCUSSION...AS OF 3:15 AM PDT TUESDAY...MODERATELY NORTHERLY
GRADIENT ALONG WITH A COMPRESSED MARINE LAYER (CURRENTLY AT 500
FEET) HAS LEAD TO GENERALLY CLEAR CLEAR CONDITIONS TO THIS POINT ACROSS
OUR AREA THIS MORNING. TEMPS ARE MOSTLY IN THE UPPER 50S TO UPPER
60S WITH SOME SPOTS MORE THAN 5 DEGREES AHEAD OF YESTERDAY.

ALL SIGNS CONTINUE TO POINT TO VERY WARM READINGS ACROSS OUR AREA
TODAY AND TOMORROW PARTICULARLY FOR INLAND SPOTS DUE TO A BUILDING
RIDGE OF HIGH PRESSURE. 850 MB READINGS ARE FORECAST TO INCREASE 1
TO 2 C WHILE 500 MB HEIGHTS INCREASE A DM. THERMAL TROUGH IS NOT
FORECAST TO MIGRATE OFFSHORE SO HIGHS WILL RANGE FROM MID 60S TO
MID 70S FOR MOST COASTAL SPOTS UP TO THE 90S AND 100 TO 110 RANGE
FOR SPOTS WELL INLAND. WILL CONTINUE TO HIGHLIGHT THE VERY WARM
READINGS IN THE SPS. PLEASE SEE THE CLIMATE SECTION BELOW FOR THE
LIST OF CURRENT RECORDS.

OUTSIDE OF THE TEMPERATURES THE OTHER AREA OF CONCERN CENTERS
AROUND POTENTIAL CONVECTION FOR WEDNESDAY INTO THURSDAY DUE TO A
POSSIBLE EASTERLY WAVE AND MOISTURE ADVECTING IN FROM THE SOUTH.
PREVIOUS RUN OF THE NAM WAS VERY BULLISH WITH POTENTIAL SHOWERS
AND THUNDERSTORMS WITH THE ECMWF KEEPING ALMOST ALL OF THE
CONVECTION TO OUR EAST. GFS ENDED UP TAKING MORE A MIDDLE OF THE
ROAD APPROACH WITH SOME SHOWERS INDICATED IN OUR CWA WITH PW
VALUES FORECAST TO NEAR 1.5 INCHES. DECIDED TO ADD SHOWERS AND
THUNDERSTORMS TO A PORTION OF OUR AREA ESPECIALLY FOR HIGHER
ELEVATION SPOTS. DEFINITELY WORTH NOTING THAT THIS IS FAR FROM
CERTAIN ESPECIALLY IN LIGHT OF THE WIDE VARIETY OF SOLUTIONS.

HIGHS WILL TREND COOLER THE REMAINDER OF THE WEEK AS THE RIDGE
SLIGHTLY WEAKENS AND HEADS TO THE EAST. TEMPS WILL CONTINUE TO
HAVE A TYPICAL WIDE SUMMER TIME RANGE WITH 60S AND 70S AT THE
COAST WHILE 80S TO MID 90S REMAIN INLAND.

&&

.AVIATION...AS OF 4:18 AM PDT TUESDAY...SHALLOW MARINE LAYER THIS
MORNING. HIGH CLOUDS ARE ONCE AGAIN MAKING IT HARD TO SEE WHERE
THE STRATUS DECK ACTUALLY IS. LATEST OBS INDICATE THE ONLY CIG AT
KMRY. HOWEVER...THE LATEST HI-RES MODELS INDICATE SOME PATCHY CIGS
MOVING INLAND THIS MORNING. IMPACT WILL BE SHORTLIVED. VFR THIS
AFTERNOON. OVERALL CONF IS MEDIUM.

VICINITY OF KSFO...TOUGH CALL THIS MORNING AS CIGS LINGER ALONG
THE COAST...THROUGH THE GOLDEN GATE AND SAN BRUNO GAP. PREVIOUS
FCST HAD CIGS...BUT CONF IS LESS FOR ACTUAL CIGS THIS MORNING.
LATEST 1KM WRF AND HRRR SHOW CIGS MOVING IN AND IMPACTING KSFO AND
KOAK BRIEFLY. THAT BEING SAID...DECIDED TO INCLUDE A TEMPO OF CIGS
BUT CONF IS LOW. VFR THIS AFTERNOON.

KSFO BRIDGE APPROACH...LESS CHANCE FOR CIGS. FORECAST VFR THIS AM
AND THIS AFTERNOON.

MONTEREY BAY AREA TERMINALS...LIFR CONDITIONS AT KMRY THROUGH
16-17Z...BUT LESS LIKELY AT KSNS. WILL HAVE TO WATCH KSNS CLOSELY
AS CIGS MAY MOVE INLAND.

&&

.CLIMATE...RECORD HIGHS FOR JUNE 30 AND JULY 1 FOR SELECTED
LOCATIONS.

.SF BAY AREA.................JUNE 30............JULY 1
 KENTFIELD..................106/1972...........103/1996
 SAN RAFAEL..................98/1999............99/1991
 NAPA.......................105/1972...........103/1972
 SAN FRANCISCO...............93/1996............92/1991
 SFO AIRPORT.................92/1996............99/1985
 OAKLAND DOWNTOWN............90/1972............92/1984
 OAKLAND AIRPORT.............90/1950............90/1985
 RICHMOND....................91/1996............97/1985
 LIVERMORE..................112/1972...........110/1950
 MOUNTAIN VIEW...............91/1972............97/1985
 SAN JOSE...................100/1996...........102/1985
 GILROY......................98/1999...........108/1972

MONTEREY BAY AREA............JUNE 30............JULY 1
 MONTEREY....................89/1996............96/1985
 SANTA CRUZ..................98/1996............99/1970
 SALINAS.....................94/1996............85/1996
 SALINAS AIRPORT.............97/1996............88/1991
 KING CITY..................109/1950...........105/1985

&&

.MARINE...AS OF 04:18 AM PDT TUESDAY...GUSTY NORTHERLY WINDS WILL
LINGER TODAY AS HIGH PRESSURE REMAINS OFF THE WEST COAST.  WINDS
WILL DECREASE WEDNESDAY THROUGH FRIDAY AS A TROUGH INLAND SHIFTS
TO THE COAST. A WEAK DISTURBANCE WILL MOVE THROUGH THE REGION ON
THURSDAY BRINGING A CHANCE OF SHOWERS AND THUNDERSTORMS TO THE
REGION.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TDAY...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 UNTIL 9 AM
             SCA...PIGEON PT TO PT PIEDRAS BLANCAS 10-60 NM UNTIL 9 AM
             SCA...SF BAY FROM NOON

&&

$$

PUBLIC FORECAST: BELL
AVIATION: MM
MARINE: MM
CLIMATE: BELL


VISIT US AT WWW.WEATHER.GOV/SANFRANCISCO

FOLLOW US ON FACEBOOK AND TWITTER AT:
WWW.FACEBOOK.COM/NWSBAYAREA
WWW.TWITTER.COM/NWSBAYAREA


USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.