927
FXUS66 KMTR 171112
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
412 AM PDT Wed Jul 17 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 351 AM PDT Wed Jul 17 2024

Today begins a warming trend into the weekend, with a short pause on
Saturday. There is potential for more intense, impactful heat for
at least the first half of next week, especially for inland
locations away from the marine layer influence.

&&

.SHORT TERM...
(Today and tonight)
Issued at 351 AM PDT Wed Jul 17 2024

Shortwave ridging in the wake of an upper level low currently moving
onshore across central Oregon will mark the beginning of a well
advertised warm up from the seasonally pleasant temperatures we`ve
seen the past few days. Highs today will increase, about five
degrees from yesterday, for most locations beyond the reach of
marine layer influence. Coastal locations won`t be left behind
entirely, with most spots close to the shoreline seeing a least a
couple ticks warmer today too. Temperatures take another step up
tomorrow as we begin to see the influence of the upper level ridge
over the Four Corners region begin to retrograde and expand back to
the west in our direction through the remainder of the forecast.

&&

.LONG TERM...
(Thursday through Tuesday)
Issued at 351 AM PDT Wed Jul 17 2024

Confidence is high that a warming trend will continue through the
extended forecast, with a brief but subtle pause on Saturday due to
a compact upper level disturbance passing over the Central Coast
providing cooler midlevel temperatures. By Sunday, the ridge of high
pressure amplifies significantly allowing for persistent troughing
to continue offshore to our north through at least Tuesday helping
to mitigate the chances for more extreme heat. Deterministic
guidance indicates decent consensus for the high to eventually
expand far enough west to deflect the polar jet farther north by
late Tuesday. Expect the warmest temperatures Wednesday and
Thursday, when the high begins to position over Nevada and central
California. Some of our elevated inland locations may see high
temperatures similar to what was realized during the recent heat
wave, but overall the magnitude of the heat and duration is not
expected to match what we saw the first half of July. Both the
ECMWF and GFS indicate a more active overall synoptic longwave
pattern capable of breaking the ridge down across our region by
the end of next week.

&&

.AVIATION...
(12Z TAFS)
Issued at 408 AM PDT Wed Jul 17 2024

Currently IFR-MVFR at all terminals with the exception of STS,
although the terminal is expected to develop a low-end MVFR
ceiling shortly. Ceilings are generally hovering in the low-end
MVFR to high-end IFR range and will likely transition between the
two through the late morning when VFR is expected to prevail.
Winds will remain onshore through the TAF period.

Vicinity of SFO...Currently IFR with westerly flow. The ceiling will
likely hover in the high-end IFR to low-end MVFR range until
clearing is expected at 16Z. Winds will prevail out of the west
through the TAF period with gusts up to 25 knots to be expected this
afternoon and evening. Another low-end MVFR ceiling is forecast to
impact the terminal overnight.

SFO Bridge Approach...Low clouds are expected to clear between
18Z and 19Z.

Monterey Bay Terminals...Currently IFR with westerly flow at MRY and
MVFR with northwesterly flow at SNS. Ceilings will likely fluctuate
between IFR and low-end MVFR until VFR is expected in the late-
morning. Winds will prevail out of the west/northwest through the
TAF period. Low-end MVFR ceilings are forecast to impact both
terminals again overnight.

&&

.MARINE...
(Today through Monday)
Issued at 408 AM PDT Wed Jul 17 2024

Winds this evening have begun to become more W/NW and will
continue to be northwesterly through the remainder of the week.
Although winds are currently gentle across much of the waters,
they will strengthen throughout the day Wednesday to become fresh
to strong by the late evening. Significant wave heights will
build to rough by Wednesday and conditions will continue to
deteriorate through the weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM this afternoon to 9 PM PDT this
     evening for Mry Bay-Pigeon Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory from 3 PM this afternoon to 9 PM PDT
     Thursday for Pigeon Pt to Pt Pinos 10-60 NM-Pt Arena to Pt
     Reyes 0-10 nm-Pt Arena to Pt Reyes 10-60 NM.

     Small Craft Advisory from 3 PM to 9 PM PDT Thursday for Pigeon
     Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory from 9 AM this morning to 9 PM PDT Thursday
     for Pt Pinos to Pt Piedras Blancas 0-10 nm.

&&

$$

SHORT TERM...JM
LONG TERM....JM
AVIATION...Sarment
MARINE...Sarment

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