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Area forecast discussion 
National Weather Service San Francisco Bay area
405 PM PST Monday Mar 2 2015

Synopsis...the weather system will continue to slide south along
the central coast later this evening and overnight along with a
gradual winding down of shower and thunderstorm activity south of
the sf Bay area. As the low moves well south of the area
Tuesday...there will be drying and warming trend across the area
by midweek with temperatures returning to above normal levels.

&&

Discussion...as of 02:06 PM PST Monday... latest visible
satellite shows the center of our weather system is presently
passing very close to San Francisco. This is generally in very
good agreement with where computer models indicated it should be
around this time. The atmosphere remains active ahead of the
system with scattered to numerous rain showers and isolated
thunderstorms. Small hail has been observed in most of the heavier
showers as freezing levels remain fairly low. Temperatures have
under performed expectations today with the clouds and showers
holding readings down. The weather system will continue its
southward movement down the coast and by late this evening will be
into Southern California. However will expect at least some
showers to linger through the evening south of the San Francisco
Bay and will keep a mention through the first half of the
overnight hours. By daybreak Tuesday the low pressure will be well
south of the area. Drier air will push into the area in the wake
of the departing system. This should bring more sun to the area
for Tuesday and thus warmer temperatures which should be in the
60s. This drier and quiet weather pattern is expected to continue
through the rest of the week as a ridge of high pressure from the
Pacific builds into the area. Temperatures will moderate each day
with highs getting into the 70s across inland areas for the middle
and latter portion of the week. Overnight lows will remain cool
with the dry airmass and so lows will drop into the middle 30s
across the interior valleys and perhaps some patchy frost. This
too will moderate as the ridge strengthens and so by Thursday
night readings overnight will warm more into the upper 30s and
low/middle 40s. Daytime highs will climb well above normal again and
the next chance of rain not in the forecast until late Monday or
Tuesday of next week.

&&

Aviation...as of 3:45 PM PST Monday...the cold core middle level
low is presently adjacent to the Bay area coastline and continues
to be driven southward by a strong upper level jet stream over
northernmost California. Isolated thunderstorms are still possible into
the early evening due to lingering yet marginal daytime heating...
weak-moderate convective potential and temporary vertical motion
sweeping southeast across the Bay area prior to jet stream subsidence
arriving later tonight. Not enough to place vicinity T-storm in
any of the 00z tafs but will closely monitor radar and amend as
needed. Otherwise clearing very late tonight into Tuesday morning
supports patchy valley fog development. Dry weather conditions
forecasted through mid-week.

Vicinity of ksfo...additional shower activity in the area of ksfo.
Otherwise VFR.

Ksfo bridge approach...similar to ksfo.

Monterey Bay area terminals...additional shower activity in the
area through this evening.

&&

Marine...as of 01:46 PM PST Monday...a storm system will move
through the coastal waters today rather quickly. The passing storm
will bring gusty northerly winds...chance of showers or an
isolated thunderstorm. Winds will gradually ease overnight into
Tuesday with generally light wind and seas forecast from midweek
and beyond as high pressure builds.

&&

Mtr watches/warnings/advisories...
... Arena to pt Reyes 10-60 nm
Small Craft Advisory...pt Reyes to Pigeon pt 10-60 nm

&&

$$

Public forecast: Johnson
aviation: canepa
marine: mm

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