Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
423 am PST Monday Feb 8 2016
Synopsis...a strong ridge of high pressure will remain positioned
over the West Coast Monday resulting in the potential for record
warmth across the Bay area and central coast today. The ridge
will begin to weaken tomorrow...initiating a cooling trend which
will bring temperatures back to seasonal norms through Valentines
day weekend. Outside of a slight chance for rain over the North
Bay Friday and Friday night, dry weather is forecast.
Discussion...as of 3:00 am PST Monday...clear skies across the
board this morning as a moderate to strong offshore flow remains
in charge. Current surface analysis indicates a greater than 15 mb
difference from sfo to wmc with nearly 2 mb offshore from sfo to
SAC. Bigger picture shows an unusually robust ridge of high
pressure overhead (586 dm at 500 mb) combined with 16c at 850 mb.
All of these factors will combine to create another round of
record to near record highs across our entire region. Many urban
spots will be in the upper 60s to middle 70s with a few locations in
the upper 70s to lower 80s.
The ridge axis will shift off to the east starting on Tuesday
which will help to gradually bring temperatures down closer to
normal values. At the same time a longwave trough will approach the
coast and by Friday rain will move from norcal up to British Columbia. For our
region, models show an outside chance of light rain hitting the
North Bay so left a mention of that in the forecast.
Behind the trough the flow will alternate between zonal and a Flat
Ridge at least into next Tuesday. After that, some indication
that moisture could become entrained in the flow and bring rain
back to our region during the middle to end of next week.
Bottom line...no public zone hazards expected through the next 7
Aviation...as of 4 am PST Monday...VFR conditions prevail with
clear skies. Limited fog potential though may see a brief period
of IFR at sts early this morning. Offshore flow is expected to
continue but models show easterlies generally below 10 kts. Slightly
stronger through Carquinez Strait...affecting apc...as well as the
Salinas valley this morning. Winds may switch to light onshore
south of the Bay Bridge with heating this afternoon.
Vicinity of ksfo...VFR will prevail with light winds.
Sfo bridge approach...similar to ksfo.
Monterey Bay area terminals...VFR. Light winds mtr. Sns moderate
southeast winds this morning becoming light this afternoon.
Beaches...as of 10:45 PM PST Friday...swells off the coast have
decreased to 7 to 8 feet tonight but the swell periods continue at
14 to 15 seconds. Although the waves are lower the longer periods
make the waves capable of generating strong rip currents and large
shore break. Additionally...water temperature is only expected to
be in the middle 50s...so those venturing into the water will also be
subject to a heightened risk of hypothermia.
Climate...record highs for Monday...
City name Feb 8th high and year
Kentfield 71 in 2006
San Rafael 72 in 1980
Napa 73 in 1987
San Francisco 74 in 2006
sfo Airport 73 in 2006
Oakland museum 77 in 2006
Oakland Airport 70 in 2006
Richmond 78 in 2011
Livermore 78 in 1917
San Jose 75 in 1987
Gilroy 78 in 1963
Monterey 81 in 1954
Santa Cruz 78 in 1954
Salinas 83 in 2006
Salinas Airport 83 in 1954
King City 84 in 2006
Marine...as of 03:27 am PST Monday...a large ridge of high
pressure over the western states will keep light winds across the
coastal waters today. Offshore winds are forecast to develop
Monday and Tuesday as the surface thermal trough drifts off the
coast. Offshore winds will be gusty in the vicinity of the coastal
mountain gaps. Onshore flow will develop by midweek as the high
weakens. A long period swell will arrive in the waters today.
Public forecast: Bell
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