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Area forecast discussion 
National Weather Service San Francisco Bay area
256 PM PDT Wednesday Oct 1 2014

Synopsis...very warm to hot weather can be expected across our
entire area at least through Friday, although many inland spots
will see much above normal temperatures into the weekend. Some
subtle cooling will return by early next week as onshore flow
returns ahead of the next upper trough.

&&

Discussion...as of 3:00 PM PDT Wednesday...temperatures have
really responded today to the offshore flow at the surface, with the
building ridge of high pressure, plus warmer air aloft. Many
locations are running 8 to 14 degrees ahead of Tuesday with most
inland spots in the 80s. Coastal locations have also seen plenty
of warming as well. Both Monterey and Half Moon Bay almost hit 80
degrees earlier. With drier air in place and fairly light winds
along with clear skies forecast overnight, look for temperatures
to rapidly drop into the 50s to lower 60s for most spots.

Decided to issue a heat advisory this morning due to the latest
guidance plus temperatures in some spots getting out to warm
levels by 9 am. Also noticed that the anomaly table show some
heights with temperatures running well over 5 Standard deviation above
normal just off the coast -- in other words strongly suggesting
that the heat will make it across our entire area instead of just
staying inland. European model (ecmwf) MOS guidance continues to produce the
warmest readings and considering the GFS/NAM values are starting
to trend that way, the bulk of the forecast uses the highest
numbers. We should see widespread 80s at the coast for both
Thursday and Friday with 90s inland. Look for a few spots to break
the 90s near the coast with some lower 100s possible well inland.
The one good side of the heat is overnight temperatures should
cool off and return back into the 50s to lower 60s. Fire weather
the offshore flow, warm temperatures, and low humidity readings
will make fire weather a definite concern.

The one big question for the forecast is when will temperatures
start to lower back closer to normal readings. Thinking right now
is by Saturday the offshore flow will start to abate which will
help the seabreeze kick in once again. Coastal areas should see
some relief, although many spots will still likely be warmer than
normal. By Sunday the seabreeze should become more prevalent
helping to further cool the coast. Inland spots should cool 3 to 8
degrees although they will still be warmer than normal.

The ridge will slowly advance to the east by next work week as a
shortwave trough advances to the coast. No rainfall is associated
with that feature. CPC continues to favor drier and warmer than
normal weather in the extended -- out to October 15th.
&&

Aviation...as of 10:15 am PDT Wednesday...clear skies under light
offshore flow. VFR to continue through the forecast period with
mostly light winds. High confidence.

Vicinity of ksfo...VFR. Late seabreeze this afternoon...otherwise
light winds.

Ksfo bridge approach...similar to ksfo.

Monterey Bay area terminals...VFR. Light winds.

&&

Climate...record high temperatures for Wednesday through Friday
(10/1 to 10/3) along with the most recent date it occurred.

Sf Bay area
location.................10/1...........10/2............10/3...
Kentfield................97/2012.......100/2012.........99/2012
San Rafael..............104/1980.......106/1980........105/1980
Napa....................106/1980.......102/1980........103/1917
San Francisco............97/1980........96/1980.........97/1985
sfo Airport..............97/1980........96/1980.........94/1985
Oakland (downtown)......103/1980.......103/1980........100/1985
Oakland Airport..........94/1952........98/1980.........95/1985
Richmond.................99/1980.......100/1980.........97/2012
Livermore...............102/1952.......106/1980........106/1980
Moffett field............93/1980........95/2012.........97/1985
San Jose.................97/1980........96/2012.........97/1985
Gilroy..................104/2001.......107/1980........106/1980

Monterey Bay area
location.................10/1...........10/2............10/3...
Monterey................103/1980.......101/1980.........96/1985
Santa Cruz..............102/1965.......102/1980........102/1980
Salinas.................104/1980.......100/1980.........97/1985
Salinas Airport.........105/1980.......103/1980.........99/1985
King City...............109/1980.......107/1980........102/1980

&&

Marine...as of 3:00 PM PDT Wednesday...northwest winds will
continue to decrease overnight as high pressure builds over the
Great Basin. Long period southwest swell moves into the coastal
waters Thursday night.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 10-60 nm until 3 am

&&

$$

Public forecast: Bell
aviation: ac
marine: ac
climate: Bell

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