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000
FXUS66 KMTR 151826
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1126 AM PDT Mon Apr 15 2024

...New AVIATION...

.SYNOPSIS...
Issued at 216 AM PDT Mon Apr 15 2024

Drier weather to persist. A warming trend is expected through the
first half of the work week.

&&

.UPDATE...
Issued at 835 AM PDT Mon Apr 15 2024

Patchy to areas of fog remain over the North Bay this morning but
conditions are showing signs of improvement as of this writing.
Elsewhere, a mix of MVFR to clear sky conditions with low clouds
anticipated to mix out throughout the late morning. The forecast
remains on track for the remainder of the day with no changes
anticipated at this time.

&&

.SHORT TERM...
(Today and tonight)
Issued at 216 AM PDT Mon Apr 15 2024

Showers have moved out of the area with dry conditions expected
through the forecast period. The 00Z KOAK sounding shows a fairly
stable atmosphere in the wake of our departing low pressure system
with guidance indicating weak surface winds and high RH values are
expected overnight. As such, there is an increased likelihood for
patchy fog to develop overnight and last through the mid-morning. At
this time areas of fog are likely to remain isolated and not meet
dense fog criteria.

Near normal morning lows in the 40`s for most areas with some areas
in wind sheltered spots and higher elevations dipping into the upper
30`s. High temperatures on Monday will be fairly seasonal with
locations along the coast in the upper 50`s and locations inland in
the mid to upper 60`s. A few locations even look to potentially peak
in the lower 70`s. This kicks off a warming trend as high pressure
builds over the West Coast with morning lows on Tuesday expected to
be in the mid to upper 40`s and high temperatures in the 60`s along
the coast and in the 70`s inland.

&&

.LONG TERM...
(Tuesday through Sunday)
Issued at 216 AM PDT Mon Apr 15 2024

Looking ahead to mid-week, warmer, drier weather reigns as ridging
builds in from the west. A warming trend will begin mid-week with
Wednesday and Thursday looking to be the warmest days. Inland highs
will reach the mid to upper 70`s and a few locations may reach the
low 80`s. Moving into Friday temperatures will cool down slightly to
the upper 60`s to mid 70`s as upper level ridging becomes more zonal
and allows for increased onshore flow.

High pressure will keep precipitation pushed northward of the Bay
Area with the CPC highlighting below average precipitation for next
6-10 days. Ensemble guidance indicates that unsettled weather may
return towards the end of April but as of now confidence remains
low.

&&

.AVIATION...
(18Z TAFS)
Issued at 1126 AM PDT Mon Apr 15 2024

A few terminals this morning holding on to MVFR CIGs, though
expecting all terminals to be VFR into the afternoon today and
through the early evening. Breezy onshore winds will begin in the
early afternoon and will diminish to become light into the
nighttime. A few terminals will see light offshore flow in the
overnight hours which may help keep stratus from forming CIGs over
terminals. Model consensus seems to be a bit fuzzy as to whether
CIGs and subsequent MVFR conditions will develop at near-shore
terminals, though have included MVFR conditions forming at Monterey
Bay and KOAK terminals in the early to mid morning of Tuesday for
now. Confidence on the development of CIGs at these terminals is
low to moderate at the moment. Models in the North Bay terminals
however seem to have good agreement in fog development overnight.
Therefore, have put LIFR conditions into the TAF for those
terminals with high confidence. Light onshore flow overnight
should help keep moisture in the North Bay at adequate levels
overnight to help allow for fog formation. Additionally, mostly
clear skies should permit good radiational cooling, further
permitting fog development.


Vicinity of SFO...Current MVFR conditions should give way this early
afternoon to VFR through the majority of the TAF period. Winds
onshore and breezy with a few stronger gusts this afternoon and
evening. Winds become light and slightly offshore into the night.
This light offshore flow should help to keep stratus away from the
terminal, though a few low clouds may manage to advect inland.
Stratus is likely to form over the SF bay waters, but not expecting
any CIG formation over the KSFO terminal in the overnight hours.
Confidence on this is moderate to high. In the afternoon of Tuesday,
onshore and breezy winds return.

SFO Bridge Approach...Model consensus has stratus forming in the
overnight of Monday into Tuesday, but dissipating towards the late
morning of Tuesday.

Monterey Bay Terminals...Current MVFR conditions should give way to
VFR and mostly clear skies in the afternoon today. FEW-SCT low
clouds may linger, but expecting CIGs to dissipate.  Winds onshore
and around 10 knots this afternoon, then easing to become light come
nightfall. Low clouds will begin to re-enter the terminal area
towards midnight, occasionally forming MVFR CIGs. As such, have put
a TEMPO group in for CIGs. Winds overnight are expected to be light
and initially variable, later developing a more offshore component.
As winds become more offshore into the mid to late morning, this
should help to erode any clouds over the terminals and bring VFR
conditions once more.
&&

.MARINE...
(Today through Saturday)
Issued at 835 AM PDT Mon Apr 15 2024

Ridging begins to build today, bringing fair weather conditions
through the remainder of the week, despite coastal stratus through
the early portion of the week. Winds will persist to be fresh out
of the NW, occasionally gusting to be strong. Moderate period
northwest swell continues through the week, though shortens in
period to around 8-10 seconds near Wednesday. Light, longer period
(18 seconds) southerly swell will also be present through the
week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 3 AM PDT
     Tuesday for Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory from 3 PM Tuesday to 3 AM PDT Wednesday for
     Pt Arena to Pt Reyes 0-10 nm.

     Small Craft Advisory until 3 AM PDT Tuesday for Pt Pinos to Pt
     Piedras Blancas 0-10 nm.

     Small Craft Advisory until 3 AM PDT Wednesday for Pt Arena to Pt
     Reyes 10-60 NM.

     Small Craft Advisory from 3 PM this afternoon to 3 AM PDT
     Wednesday for Pigeon Pt to Pt Pinos 10-60 NM.

&&

$$

SHORT TERM...Kennedy
LONG TERM....Kennedy
AVIATION...AC
MARINE...AC

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