FXUS66 KMTR 071128
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
428 AM PDT Thu May 7 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1124 PM PDT Wed May 6 2026
- Warming and drying trend beginning today through the early
part of next week
- Temperatures peaking Monday
- Moderate risk for heat-related illnesses for sensitive
populations across the inland valleys beginning this weekend
&&
.SHORT TERM...
Issued at 1124 PM PDT Wed May 6 2026
(Tonight through Friday)
Low clouds are building inland from the coast, covering the bays
and working their way into some of the interior valleys. Expect
chances for pockets of fog overnight, with the strongest chances in
the North Bay. Because of the marine layer's influence and the
covering of stratus, overnight temperatures look fairly mild woth
most areas seeing lows in the 50s and upper 40s. Only far interior
valleys and higher peaks will fall further into the 40s.
Thursday will see a slow erosion of the lower cloud cover, keeping
certain areas on the cooler side compared to the areas that stay
clear. Inland cloud cover will start clearing in the mid morning,
however areas around the bays will keep cloud cover into the late
morning and early afternoon. The immediate coast looks to keep cloud
cover through the day with moderate to breezy winds, making for much
cooler highs than the rest of the area. Expect highs around 60
degrees along the immediate coast, then the 60s and 70s for areas
more inland, and into the 80s for areas not experiencing the morning
cloud cover. A few areas in the far interior portions of Monterey Co
look to break 90 degrees.
Thursday night will offer fairly similar conditions to what we're
seeing tonight, but with an earlier inland push of coastal stratus.
This will lead to low clouds filling around the SF Bay and Monterey
Bay in the mid evening and will cause a quicker cool-down. The lower
clouds and the marine layer influence look to go slightly farther
inland. This wont have too much of an effect in morning lows, but
will make some areas a slightly cooler for Friday as they linger
into the late morning and early afternoon.
While most areas will see slightly cooler conditions for Friday, a
ridge builds to the north,leading to a small increase in
temperatures for the interior North Bay. This will get things back
&&
.LONG TERM...
Issued at 1124 PM PDT Wed May 6 2026
(Friday night through next Wednesday)
Friday night will continue to see the affects of the building ridge
with a compression of the marine layer and a reduction in the
overnight inland push of coastal stratus. Cloud cover will still be
prevalent along the coast, but will struggle to enter the SF Bay and
reach more of the inland areas.
The reduction of marine influence along with the building ridge
calls for much more of the inland areas to break into the 80s for
Saturday, while the coast sits in the low 60s, and the slightly
inland areas stay in the 90s. A few of the more inland areas look to
break into the mid 90s.
The reduction of the marine layer and building of the ridge
continues into Monday, which looks to be the hottest day of the
current forecast. Most of the interior valleys look to break into
the 90s with widespread 80s for all but the near-coastal areas
seeing the 60s and 70s. A building of a thermal belt will also call
for much warmer lows on the higher peaks (60s and a few 70s) and
will lead the peaks into the 90s as well from that warm start. Again
the hottest area of the CWA looks to be interior Monterey Co, which
will have a few spots looking to break 100 degrees.
The longer term forecast shows good cooling for Tuesday, yet things
will stay on the warmer side as the ridge begins to flatten and push
east. This will call for a slightly more zonal flow, leading to weak
onshore winds into the mid week. The national blend of models looks
to continue the steady cooling trend in the late week, but the
latest batch of long term model updates are hinting more at another
ridge building, which will warm things up again in the late week.
The current forecast follows the blend, but as things continue to
update, more considerations may need to be made for the potential
warming trend.
&&
.AVIATION...
(12Z TAFS)
Issued at 410 AM PDT Thu May 7 2026
The marine layer is back in earnest this morning. Low stratus
clouds are filling the valleys and bringing flight condition impacts
to all terminals with IFR-LIFR ceilings this morning. The trend
today will be typical of a Summer day, with several hours of
clearing from late morning through the afternoon, before ceilings
return this evening. The 12Z balloon found the marine layer depth
and cloud tops to be around 1800 feet.
Vicinity of SFO...Low MVFR-IFR stratus will continue through the
morning. The earliest possible clearing time is 17Z, with chances
improving steadily through the subsequent couple hours. Onshore
winds will be strong this afternoon, with sustained winds up to 20
knots expected. Marine layer stratus will return sometime between 02Z
to 09Z. The exact ceiling return time is the most uncertain part
of the TAF for now, but it will very likely return at some point
this evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...Fully socked in. MRY is reporting
ceilings of 100 feet with 4 mile visibility. These very poor
conditions are likely temporary, but LIFR-IFR conditions will
persist through the early to mid morning hours. Expect gradual
improvement around 18Z with clearing around 21Z at MRY, and a
quicker clearing timeline at SNS. There is a 20% chance that MRY
doesn't clear at all today, but the ceilings will at least lift to
MVFR during the afternoon in the worst case scenario.
&&
.MARINE...
(Today through Tuesday)
Issued at 410 AM PDT Thu May 7 2026
NW winds will increase to a strong breeze by tonight and remain
strong through the weekend. Seas will steadily build through the
day in response to the stronger winds.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 PM this evening to 3 PM PDT Saturday
for Pt Arena to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 AM Friday to 3 PM PDT Saturday for
Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
NM-Pt Arena to Pt Reyes 10-60 NM-Pt Reyes to Pigeon Pt 0-10
nm.
Small Craft Advisory from 9 AM this morning to 3 PM PDT Saturday
for Pt Pinos to Pt Piedras Blancas 0-10 nm.
&&
$$
SHORT TERM...Murdock
LONG TERM....Murdock
AVIATION...Flynn
MARINE...Flynn
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Prepared by Boulder-Creek.com Weather at: Thu May 7 08:30:03 PDT 2026
From the National Weather Service
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