Area Forecast Discussion
Issued by NWS San Francisco Bay Area, CA

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FXUS66 KMTR 260104
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
604 PM PDT WED MAY 25 2016

.SYNOPSIS...A building ridge of high pressure along the coast will
result in a gradual warming trend through the upcoming weekend
along with dry weather conditions.

.DISCUSSION...as of 01:50 PM PDT Wednesday...Low cloud cover over
inland areas of the region continue to erode this afternoon with
daytime heating. Meanwhile, do see some cumulus developing over
the higher terrain as expected with lingering moisture aloft. The
most development remains over the inland portion of the North Bay
Mountains where a few showers and potentially a thunderstorm or
two will be possible this afternoon. Otherwise, most locations
across the region will remain dry as the main mid/upper level
system over southern California shifts to the east today and
tonight. Low clouds will likely spread back inland this evening
and persist through Thursday morning. In addition, patchy drizzle
is once again expected along coastal areas overnight into Thursday
morning.

A building ridge of high pressure will become the dominate
weather feature across the region for the remainder of the week
and result in a gradual warming trend. By tomorrow afternoon, most
inland locations will be around 5 degrees warmer compared to this
afternoon. While the marine influence will keep coastal areas
cooler, may see a few degrees of warming with more afternoon
sunshine on both Thursday and Friday.

The ridge will strengthen and temperatures will warm aloft
through the upcoming Memorial Day Holiday Weekend. This will
result in inland temperatures warming back into the upper 70s to
mid 80s with coastal areas generally in the upper 60s to lower
70s. While overnight and morning coastal stratus will likely
continue as a result of onshore flow, dry weather conditions are
expected region- wide into early next week.

&&

.AVIATION...as of 6:04 PM PDT Wednesday...Moderate onshore winds
are bringing areas of coastal low clouds and fog back inland
though now beginning to see some clearing from Point Reyes to the
Golden Gate. Areas MVFR cigs are reported along the immediate
coast and over the East Bay late this afternoon. Areas MVFR and
IFR cigs develop this evening but lowering confidence on timing
per late afternoon coverage seen visible imagery. VFR well inland
but a gradual increasing in MVFR cig coverage is forecast tonight
and Thursday morning.

High pressure over the eastern Pacific will build in over NorCal
through Thursday. The ACV-SFO gradient is 3.4 mb and approx 2 mb
stronger than forecast by the most recent NAM model. The ACV-SFO
gradient reaches to 5 or 6 mb Thursday then near 9 mb Friday.
Typically as the northerly gradient reaches/exceeds 5-6 mb ocean
based low clouds and fog tend to stay confined to the immediate
coast and/or out over the coastal waters and we may see hints of
this as soon as Friday.

The Bodega Bay profiler shows low level warming in the last 24
hours. Steady warming returning to the 925 mb and 850 mb levels
area-wide supports a redeveloping marine layer as the low that
recently affected our area departs.

Vicinity of KSFO...MVFR cig tonight. Gusty westerly winds to around
25 knots til 05z. Westerly winds pick up again Thursday afternoon and
evening.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR cigs trending lower to IFR this
evening. Onshore winds persist this period with tendency for
coastal stratus and fog to persist Thursday/Thursday night as a
gradually strengthening northerly gradient enhances NW winds over
the Monterey Bay.

&&

.CLIMATE...Fun climate facts -- downtown San Francisco has picked
up nearly 23" since October 1st which is 99% of average. We are
currently just 0.12" drier than normal. This is the most rainfall
in San Francisco for the same period since 2010-2011. It is also
nearly double the amount recorded October 1st, 2013, to May 25th,
2014.

&&

.MARINE...as of 09:30 AM PDT Wednesday...Building high pressure
will result in gusty northerly winds over the coastal waters today
through the weekend. Winds will be strongest in the outer waters
north of Point Reyes. Hazardous conditions from fresh squared
seas will exist as northwest seas build to match the period today
and tomorrow.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pigeon Pt to Pt Pinos 0-10 nm
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pt Reyes to Pigeon Pt 0-10 nm
             SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm
             SCA...SF Bay until 9 PM
             SCA...Mry Bay until 9 PM

&&

$$

PUBLIC FORECAST: RGass
AVIATION: Canepa
MARINE: MM
CLIMATE: Bell


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