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

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FXUS66 KMTR 230403

Area Forecast Discussion
National Weather Service San Francisco Bay Area
903 PM PDT Sat Apr 22 2017

.SYNOPSIS...A dry front brought cooler weather to the Bay Area
today and cool conditions will continue into Sunday, along with
patchy morning low clouds. Unsettled weather is expected
through the first half of next week, with periodic rain chances
across mainly the northern portion of our area. Dry weather will
return to all areas later next week with warmer temperatures
expected by week`s end.


.DISCUSSION...As of 9:00 PM PDT Saturday...A mostly dry cold front
swept across our region today, bringing widespread clouds and
cooler temperatures. High temperatures today were as much as ten
degrees cooler compared to Friday. There were also a few light
showers reported in the North Bay, but these showers mostly
produced only trace amounts of precipitation.

Patchy low clouds have developed near the coast this evening, and
these clouds will likely linger into Sunday morning. Mostly sunny
conditions are expected by Sunday afternoon. Look for another
cool day on Sunday with highs mostly in the 60s. Northwest winds
will increase by afternoon and locally breezy conditions are
expected near the coast.

A series of weak weather systems moving through northwest flow
aloft are forecast to track across northern California during the
first half of the coming work week. These systems may produce
periodic light rain across the northern portion of our forecast
area (mainly North Bay) from Monday through Wednesday. Elsewhere,
dry and seasonably cool conditions will continue.

The models are in general agreement in developing dry weather
across our entire area by Thursday of next week, with warming
expected late in the week and into next weekend as an upper ridge
develops just offshore.

&& of 6:04 PM PDT Saturday...VFR is reported per metar
observations and web cams also show good to very good visibilities.
Air mass water vapor content per dewpoint temperatures in the upper
40s to 50s is highest along the immediate coast and nearest the
bays where few-sct low clouds continue to develop today. Post
frontal lower level cooling (-3C to -6C at 925 mb level) tonight
will continue to erode already weakened lower level inversions
over the north Central Coast with no evidence of inversions
remaining over the Bay Area this afternoon. Inherited tafs look
good, only minor adjustments were made e.g. to delay forecast
arrival of MVFR cig at KOAK this evening.

Vicinity of KSFO...W-NW winds 15-20 knots tonight. VFR tempo MVFR cig
12z-16z Sunday. W-NW winds 10-15 knots Sunday with afternoon and evening
gusts to 25 knots.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...W-SW winds 5-10 knots. VFR with MVFR cigs
developing early Sunday morning. VFR forecast to return by late

&& of 5:19 PM PDT Saturday...A weak front is moving
through the region with gentle long period swells currently over
the waters. Tonight northwest wind and seas will begin to increase
and then strengthen Sunday afternoon and night. Strong northerly
winds will persist along along the Big Sur coast down to Point
Piedras Blancas at least through Monday. Late season cold fronts
moving towards cape mendocino will keep nw wind and seas in place
through much of next week.


     .Tngt...SCA...Pt Arena to Pt Reyes 0-10 nm from 9 PM
             SCA...Pt Reyes to Pigeon Pt 0-10 nm from 9 PM
             SCA...Pigeon Pt to Pt Pinos 0-10 nm from 9 PM
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm




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