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

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000
FXUS66 KMTR 020351
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
851 PM PDT FRI AUG 1 2014

.SYNOPSIS...TYPICAL SUMMER WEATHER PATTERN FORECAST ACROSS OUR
AREA WITH COASTAL LOW CLOUDS AND FOG EXTENDING INTO THE VALLEYS
DURING THE NIGHT AND MORNING HOURS. OTHERWISE MOSTLY CLEAR SKIES
AND DRY WEATHER IS EXPECTED. A GRADUAL COOLING TREND IS FORECAST
FOR THE INLAND VALLEYS OVER THE NEXT FEW DAYS.

&&

.DISCUSSION...AS OF 8:50 PM PDT FRIDAY...FRIDAY WAS A TYPICAL MID-
SUMMER DAY ACROSS MOST OF THE REGION WITH LOW CLOUDS AND FOG
HUGGING THE COAST AND MOSTLY SUNNY CONDITIONS INLAND.
TEMPERATURES WERE NEAR NORMAL IN MOST AREAS EXCEPT IN THE HILLS
AND INLAND VALLEYS WHERE VERY WARM TO HOT CONDITIONS PREVAILED.
THE FORT ORD PROFILER AND 00Z OAK SOUNDING SHOW A VERY WARM AIRMASS
JUST ABOVE THE MARINE BOUNDARY LAYER WITH TEMPERATURES AT 30 DEG
C AT 2000 FEET. THIS HOT AIRMASS ALOFT ALLOWED AREAS CUT OFF FROM
ANY MARINE AIR INFLUENCE (E.G., HILLS ABOVE 1500 FEET AND INLAND
VALLEYS) TO WARM WELL INTO THE 90S TODAY...AND TO OVER 100 IN THE
WARMEST INLAND VALLEYS. ISOLATED SPOTS IN THE EAST BAY REACHED THE
CENTURY MARK BUT TODAY`S WARMEST LOCATIONS WERE ACROSS INTERIOR
MONTEREY COUNTY AND SAN BENITO COUNTY. THE AFTERNOON HIGH AT
PINNACLES NATIONAL PARK WAS A SIZZLING 110...AND ARROYO SECO WAS
NOT FAR BEHIND WITH A 109.

THE UPPER RIDGE RESPONSIBLE FOR THE VERY WARM AIRMASS OVER OUR
AREA IS CURRENTLY CENTERED OVER SOUTHEASTERN NEVADA. THE MODELS
ARE IN AGREEMENT IN MOVING THIS RIDGE GRADUALLY TO THE EAST OVER
THE NEXT FEW DAYS AND DEVELOPING A WEAK UPPER TROUGH OFF THE
CALIFORNIA COAST. THESE DEVELOPMENTS WILL BRING ABOUT A GRADUAL
COOLING OF THE AIRMASS ALOFT THROUGH MONDAY AS WELL AS AN INCREASE
IN THE DEPTH OF THE MARINE LAYER. THE RESULT WILL BE A COOLING
TREND FROM TOMORROW THROUGH MONDAY...WITH THE MOST SIGNIFICANT
COOLING EXPECTED INLAND. THE HILLS AND INLAND VALLEYS ARE
EXPECTED TO COOL ABOUT FIVE DEGREES TOMORROW AND AN ADDITIONAL 10
TO 15 DEGREES BY MONDAY. AREAS CLOSER THE COAST WILL SEE MUCH MORE
MODEST COOLING. TEMPS ARE EXPECTED TO LEVEL OFF BY TUESDAY AND
REMAIN NEAR NORMAL FOR THE REMAINDER OF NEXT WEEK.

AS THE WEAK UPPER TROUGH DEVELOPS OFF THE CALIFORNIA COAST THIS
WEEKEND...THE FLOW ALOFT OVER CA WILL BACK FROM SOUTHWEST TO DUE
SOUTH. THIS WILL ALLOW MONSOON MOISTURE TO CREEP INTO SOUTHEASTERN
MONTEREY COUNTY BY SATURDAY NIGHT AND THEN MOVE NORTHWARD ALONG
THE EASTERN FRINGES OF THE SF BAY AREA BY SUNDAY NIGHT. AT THIS
POINT IT LOOKS LIKE MID/UPPER LEVEL MOISTURE AND INSTABILITY WILL
NOT BE SUFFICIENT FOR CONVECTIVE DEVELOPMENT ANYWHERE IN OUR AREA
AND THAT ALL CONVECTION WILL REMAIN TO OUR EAST THIS WEEKEND. IN
ANY CASE...THIS IS SOMETHING TO KEEP AN EYE...PARTICULARLY
CONSIDERING HOW FREQUENTLY WE`VE SEEN MONSOON MOISTURE AND
ISOLATED SHOWERS/THUNDERSTORMS IN OUR AREA OVER THE PAST MONTH.

&&

.AVIATION...AS OF 5:15 PM PDT FRIDAY...MARINE LAYER DEPTH HAS NOW
COMPRESSED DOWN TO ABOUT 1300 FT. STRATUS BLANKETS MUCH OF THE
COAST...WITH LATEST SATELLITE AND WEBCAM IMAGERY SHOWING A NARROW
TONGUE EXTENDING THROUGH THE GOLDEN GATE TO NEAR THE NORTH
BERKELEY SHORELINE. IN GENERAL...EXPECT STRATUS EVOLUTION
OVERNIGHT TO BE PRETTY SIMILAR TO LAST NIGHT...WITH CIGS
DEVELOPING AT MONTEREY BAY TERMINALS WITHIN THE NEXT FEW
HOURS...BUT NOT UNTIL AFTER MIDNIGHT AT KOAK AND KSTS. VFR CONDS
EXPECTED TO CONTINUE THROUGH THE NIGHT AND ON SATURDAY AT BOTH KSFO
AND KSJC.

VICINITY OF KSFO...MEDIUM CONFIDENCE IN FORECAST THAT VFR CONDS
WILL CONTINUE THROUGH THE NIGHT AND SATURDAY MORNING. CURRENT
WEST WINDS TO AROUND 20 KT WILL GRADUALLY DIMINISH AS THE EVENING
PROGRESSES.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...EXPECT CIGS TO DEVELOP WITHIN THE NEXT
FEW HOURS. CONFIDENCE IS LOWER HOWEVER ON OVERNIGHT EVOLUTION OF
CIG HEIGHT AND VISIBILITY.

&&

.MARINE...AS OF 3:00 PM PDT FRIDAY...NORTHWEST WINDS WILL INCREASE
OVER THE NORTHERN OUTER WATERS AS HIGH PRESSURE BUILDS OVER THE
EASTERN PACIFIC. ELSEWHERE WINDS AND SEAS WILL REMAIN LIGHT
THROUGH THE WEEKEND.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .TNGT...SCA...PT ARENA TO PT REYES 10-60 NM
             SCA...SF BAY NORTH OF THE BAY BRIDGE UNTIL 9 PM

&&

$$

PUBLIC FORECAST: DYKEMA
AVIATION: BLIER
MARINE: AC

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