Scientific Forecaster Discussion
Area forecast discussion
National Weather Service San Francisco Bay area
257 PM PDT Thursday Jul 2 2015
Synopsis...showers and embedded thunderstorms will remain
a slight possibility this evening generally over the North Bay. A
slight cooling trend will continue through the weekend with
generally dry weather conditions expected into next week.
Discussion...as of 3:00 PM PDT Thursday...muggy day for our area
today with some spots seeing dew points into the 60s while the
koak sounding this morning came in around an inch and a half. As
expected temperatures are running cooler compared to yesterday in
many spots thank to more cloud cover. In fact...a few spots in the
north and East Bay are running nearly 15 degrees less compared to
Thursday. First forecast issue involves the next 8 hours and the
potential for showers and thunderstorms. Current kmux radar has
just light returns indicated for san bentio and southeast Monterey County
and in most cases that is likely just virga. Model guidance for
most of the day had been showing the focus switching more to the
North Bay by the evening. Last few runs of the hrrr have been
trending drier with the 20z version now keeping it almost entirely
dry. Will just keep a mention for a slight chance of showers and
thunderstorms going in light of previous solutions. Shower chances
should end by sunset and not be in our County Warning Area for Friday as the
focus shifts well to our north and east.
Outside of that...the main weather story will be continued cooling
as the marine layer deepens plus the flow becomes more onshore.
Highs for Friday into the first part of next week will range from
60s to middle 70s at the coast with upper 70s to lower 90s for inland
locations. These near normal values are now forecast to hold
through all of next week out to the middle of July.
Aviation...as of 11:15 am PDT Thursday...all terminals have now
gone VFR and should remain that way through at least 01z.
Possible showers at all spots although would favor north and East
Bay after 0z. Ceilings forecast to return tonight at or under 010
feet. High confidence through 02z.
Vicinity of ksfo...passing showers possible through early this
afternoon. Will keep conditions VFR despite some passing showers.
Ceilings possibly under 010 by 12z. High confidence through 06z.
Ksfo bridge approach...similar to ksfo.
Monterey Bay area terminals... VFR through 02z with a passing
shower also possible. Ceilings lowering after that point potentially
to 003 after 05z. High confidence through 02z.
Marine...as of 3:00 PM PDT Thursday...high pressure over the
interior and a trough near the coast will create a prolonged
period of light wind and seas across the coastal waters right
through the Holiday weekend.
... Bay until 9 PM
Public forecast: Bell/rgass
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