FXUS66 KMTR 081944
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1244 PM PDT Thu Oct 8 2026
...New SHORT TERM, LONG TERM...
.KEY MESSAGES...
Updated at 1243 PM PDT Thu Oct 8 2026
- Hot inland temperatures continue Thursday
- Sharp cool-down this weekend and early next week
- Coastal flooding during high tides and large swell this weekend
- Light rain possible early next week
&&
.SHORT TERM...
Issued at 1243 PM PDT Thu Oct 8 2026
(This evening through Friday night)
A Heat Advisory remains in effect until 10 PM this evening for
much of the interior Bay Area and Central Coast as 500 mb high
pressure remains in place over the region. Temperatures across the
interior will be in the some 10-20 degrees F above seasonal
averages again this afternoon with cooler conditions near the
coast given the shallow marine layer around 500 feet in depth.
Overnight temperatures will still remain warm in the higher
terrain tonight with 60s to low 70s expected and generally in the
50s in the lower elevations. This is as a mid/upper level trough
begins to develop off of the British Columbia coastline and allows
for the marine layer to deepen.
Friday will be noticeable cooler as the aforementioned trough
deepens along the West Coast bringing temperatures closer to
normal for this time of year. Thus, expecting temperatures to cool
into the low-to- upper 80s in the inland valleys and the warmest
interior portions of the region to reach into the lower 90s.
Breezier onshore winds are also expected on Friday afternoon and
evening along the coast and wind-prone gaps, passes, and valleys.
This will keep temperatures near the coast in the 60s to lower
70s.
A Coastal Flood Advisory remains in effect for bayshore locations
adjacent to the San Pablo Bay with up to 1.2 feet of inundation
above ground level in low-lying areas during times of peak high
tides. On Friday morning, the areas adjacent to the San Francisco
Bay and Monterey Bay are added to the advisory through at least 3
PM Tuesday.&&
.LONG TERM...
Issued at 1243 PM PDT Thu Oct 8 2026
(Saturday through next Wednesday)
Additional cooling is expected by Saturday as a dry frontal
boundary drops southward across the Bay Area and Central Coast and
the mid/upper level trough deepens along the West Coast. Thus,
temperatures will cool to below seasonal averages Saturday through
early next week. Onshore winds will be a bit stronger than those
on Friday with gusts between 30-40 mph along the coast and in the
wind- prone gaps, passes, and valleys. Locally stronger gusts will
be possible in these areas this weekend.
The NBM and global forecast models continue to indicate a chance
for rain showers across the southern portion of the Bay Area and
Central coast Sunday evening through Monday. This is as an upper
level cut- off low pressure system and remnant moisture from
Tropical Storm Rachel push into the Central Coast. However, not
expecting widespread measurable rainfall at this time. Winds ease
late Sunday and into early next week as the through axis shifts
inland. Cooler conditions are forecast to persist through midweek
as troughing persists over the West Coast. Then, as we head into
the latter part of the upcoming week, a gradual warming trend is
forecast by the WPC Cluster Analysis as high pressure builds in
from the eastern Pacific.
&&
.AVIATION...
(18Z TAFS)
Issued at 1037 AM PDT Thu Oct 8 2026
Patchy fog and LIFR stratus lingers at the immediate coast with the
rest of the region remaining VFR through the daytime. A gentle to
moderate onshore pattern wind develops in the afternoon and
evening hours. This evening and tonight, the marine layer is
expected to rebuild and thicken as large scale ridging moves
eastwards, allowing for some improved inland expansion of the
stratus deck. Forecast confidence is moderate for stratus extent
and ceiling heights, but expect some inland development into the
North bay valleys, SF Bay, and Salinas Valley overnight. Stratus
begins to retreat back to the coastal regions Friday morning.
Vicinity of SFO... Moderate confidence for VFR conditions through
the TAF period with some scattered clouds possible late tonight.
Higher confidence in stratus impacts at OAK. Moderate west-northwest
winds will develop in the afternoon and evening hours, with light
winds overnight into the morning.
SFO Bridge Approach... Similar to SFO
Monterey Bay Terminals... Lingering fog and LIFR stratus is expected
to lift imminently at MRY but potentially persist through the
afternoon along the immediate coast. Otherwise VFR conditions remain
prevalent through the day with gentle to moderate northwest winds in
the afternoon hours. IFR-LIFR stratus develops this evening with
moderate confidence for fog, not expected to clear out until the TAF
period ends on Friday morning, or shortly thereafter.
&&
.MARINE...
(Today through Tuesday)
Issued at 907 AM PDT Thu Oct 8 2026
Moderate to fresh northwesterly breezes and moderate seas will
prevail today. Conditions deteriorate Friday and into the weekend
as northerly breezes increase to become strong to near gale across
the coastal waters, Monterey Bay, and through the Golden Gate
Gap. Gale force gusts are expected across the northern outer
waters and the coastal jet region of Point Reyes. These winds will
build rough to very rough seas. Long period southerly swell
arrives Friday, with long period northwesterly swell arriving
Sunday, creating a confused sea state.
&&
.FIRE WEATHER...
Issued at 428 AM PDT Thu Oct 8 2026
Hot and dry conditions will lead to elevated fire weather conditions
across the interior and higher terrain Thursday. Temperatures 10 to
20 degrees above normal and poor minimum relative humidity will
continue away from the compressed marine layer at the coast
Thursday. The higher terrain will experience active thermal belting,
little-to-no recovery with nocturnal drying across the highest
peaks, and thus prolonged burn periods. Winds remain the limiting
factor, with diurnal winds prevailing except for light
northerly/offshore flow overnight across the higher terrain. Even
though conditions become cooler and more humid Friday, windier
conditions will keep elevated fire weather conditions across the
interior and higher terrain through Friday.
Sarment
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory from 9 AM Friday to 3 PM PDT Tuesday for
CAZ006-508-529-530.
Heat Advisory until 10 PM PDT this evening for CAZ503-504-506-
508-510-512>518.
Coastal Flood Advisory until 4 PM PDT Wednesday for CAZ506.
PZ...Small Craft Advisory from 3 AM to 3 PM PDT Friday for Pt Arena
to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...RGass
LONG TERM....RGass
AVIATION...DialH
MARINE...DialH
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Prepared by Boulder-Creek.com Weather at: Thu Oct 8 16:30:03 PDT 2026
From the National Weather Service
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