000
FXUS66 KMTR 150530
AFDMTR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN FRANCISCO BAY AREA
1030 PM PDT FRI JUN 14 2013

.DISCUSSION...AS OF 8:10 PM PDT FRIDAY...NORTHERLY FLOW ALOFT LAST
NIGHT AND THIS MORNING MAINTAINED CLEAR SKIES IN ALL AREAS THROUGH
THE DAY TODAY...AND ALSO DELAYED THE ONSET OF THE SEABREEZE. THE
RESULT WAS WARMER TEMPERATURES. AFTERNOON HIGHS WERE ANYWHERE FROM
5 TO 10 DEGREES ABOVE NORMAL ACROSS THE ENTIRE FORECAST AREA.
TODAY WILL BE THE WARMEST DAY OUR AREA WILL SEE FOR A
WHILE...POSSIBLY FOR THE NEXT SEVEN DAYS.

ONSHORE FLOW IS PICKING UP STEAM THIS EVENING AS THE NORTHERLY SURFACE
PRESSURE GRADIENT FROM ACV TO SFO DIMINISHES AND AS THE ONSHORE
GRADIENT FROM THE COAST TO THE CENTRAL VALLEY INCREASES. THERE IS
STILL ENOUGH DRY AIR IN THE BOUNDARY LAYER TO MAINTAIN CLEAR SKIES
AT THE COAST AS OF EARLY THIS EVENING. THOSE CLEAR SKIES ARE NOT
EXPECTED TO LAST MUCH LONGER. THE FORT ORD PROFILER SHOWS A
CLEARLY-DEFINED MARINE INVERSION AT ABOUT 1000 FEET. EXPECT LOW
CLOUDS TO DEVELOP NEAR THE COAST AS ONSHORE FLOW CONTINUES TO
MOISTEN THE BOUNDARY LAYER. LOW CLOUDS AND PATCHY FOG WILL
PROBABLY BEGIN TO DEVELOP NEAR THE COAST SHORTLY AFTER SUNSET AND
THEN PROCEED TO DEVELOP LOCALLY INLAND BY SUNRISE SATURDAY
MORNING. TEMPERATURES ON SATURDAY WILL BE UP TO 10 DEGREES COOLER
THAN TODAY DUE TO THE INLAND INFLUX OF MARINE AIR OVERNIGHT.
TEMPERATURES ON SATURDAY WILL FALL BACK TO NEAR NORMAL...OR EVEN
SLIGHTLY BELOW NORMAL. NOT MUCH CHANGE IS EXPECTED INTO SUNDAY.

AN UPPER LEVEL LOW IS CENTERED ABOUT 600 MILES WEST OF SEATTLE
THIS EVENING. THE ASSOCIATED UPPER TROUGH IS FORECAST TO
GRADUALLY DEEPEN OFFSHORE THROUGH THE WEEKEND. THE TROUGH IS THEN
PROJECTED TO MOVE SLOWLY EASTWARD TOWARDS THE WEST COAST ON MONDAY
AND TUESDAY OF NEXT WEEK AND FINALLY INLAND ACROSS NORTHERN AND
CENTRAL CALIFORNIA ON WEDNESDAY. INLAND TEMPERATURES WILL COOL
WELL BELOW NORMAL BY TUESDAY AS THE TROUGH APPROACHES AND THEN
REMAIN WELL BELOW NORMAL ON WEDNESDAY. THE MARINE LAYER WILL
LIKELY MIX OUT BY TUESDAY AS 850 MB TEMPERATURES DROP TO 10 DEG C
OR LESS. THUS...COASTAL AREAS PROBABLY WON`T COOL ALL THAT MUCH
MORE ON TUESDAY AND WEDNESDAY SINCE SUNSHINE THERE SHOULD BECOME
MORE PLENTIFUL. GRADUAL WARMING IS THEN EXPECTED...ESPECIALLY FOR
INLAND AREAS...ON THURSDAY AND FRIDAY AS THE UPPER TROUGH MOVES
OFF TO THE EAST.

&&

.AVIATION...AS OF 10:30 PM PDT FRIDAY...NORTHERLY GRADIENT HAS
SUBSIDED AND RAPID STRATUS DEVELOPMENT UNDERWAY ALONG THE SAN
MATEO AND MONTEREY COASTS AT THIS HOUR. MARINE LAYER DEVELOPING TO
AROUND 1000 FT ON THE FT ORD PROFILER...TO DEEPEN TO 1500 FT
TONIGHT. CIGS THAT GET INTO SF BAY LOOK TO BE PATCHY AND SHORT
LIVED. ONSHORE GRADIENT FORECAST OVER 4 MB BY 00Z BRINGING IN
MODERATE WEST WINDS AGAIN IN THE AFTERNOON. STRATUS LIKELY AGAIN
TOMORROW EVENING.

VICINITY OF KSFO...VFR EXCEPT POSSIBLE PATCHY STRATUS NEAR
SUNRISE. CIGS MOSTLY NORTH AND EAST OF TERMINAL. WINDS CONTINUE TO
DECREASE OVER THE NEXT FEW HOURS...PICKING UP MID AFTERNOON TOMORROW.

KSFO BRIDGE APPROACH...SIMILAR TO KSFO.

MONTEREY BAY AREA TERMINALS...STRATUS THROUGH MID MORNING
TOMORROW...CLEARING BACK TO THE COAST. WINDS BECOMING ONSHORE TO
10 TO 15 KT IN THE AFTERNOON

&&

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

&&

$$

PUBLIC FORECAST: DYKEMA
AVIATION/MARINE: AC

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