FXUS66 KMTR 090046
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
546 PM PDT Mon Jun 8 2026
...New AVIATION...
.KEY MESSAGES...
Updated at 320 PM PDT Mon Jun 8 2026
- Chance for coastal drizzle this evening into early Tuesday
- Warmer and dry weather expected Wednesday - Saturday
- Moderate risk of heat-related illnesses for interior locations on
Wednesday and Thursday
- Elevated fire weather concerns for the interior North Bay and
the East Bay and Santa Clara Hills late Wednesday and Thursday
&&
.SHORT TERM...
Issued at 320 PM PDT Mon Jun 8 2026
(This evening through Tuesday)
A disturbance will continue to track through the PacNW through
tomorrow morning. So far, this has spread high clouds across the
region with radar showing light returns over the North Bay. Looking
at sounding data, profiles have moistened some, but favor a drier
air mass. As the system progresses and a front approaches, we could
see this interact with the marine layer later this evening and into
Tuesday morning. This would result in coastal drizzle and perhaps
even some light rain/coastal drizzle for the northwestern portion of
Sonoma County. The front is expected to pass across the region
Tuesday morning, with drier air working in behind it. Skies will
begin will clear behind the front, which will kick off the warming
trend for the week. Highs for Tuesday will be in the mid 70s to mid
80s for interior valley locations and for the interior mountains.
Along the coast, temperatures will range from the upper 50s to low
70s.
&&
.LONG TERM...
Issued at 320 PM PDT Mon Jun 8 2026
(Tuesday night through next Sunday)
The upper level pattern begins to change on Friday as high pressure
builds over the Eastern Pacific, while troughing sets up over the
west. This will lead to a stretch of warmer and drier weather
through the rest of the forecast period. Some uncertainty remains in
a few areas, such as where does the upper low go? The latest
guidance continues to favor a inside slider type upper level trough,
leading to offshore flow for our neck of the woods Wednesday through
Thursday morning. The strongest winds look to occur over the
interior North Bay region and along the East Bay and the Santa Clara
Hills, where gusts up to 35-55mph are expected over favored ridges,
gaps, and passes.
On Thursday, ridging builds in ever so slightly leading to the
warmest day of the week. Widespread moderate HeatRisk is expected,
with temperatures rising in to the 90s for many interior valleys,
with some areas even cracking 100. Along the coast, temperatures
will be warm as well, ranging from the mid 60s along the immediate
coast to to mid 80s inland. Warmer weather lasts into the weekend,
as the ridge holds over the EPac; however, temperatures will falter
a few degrees each day. There is a sign we could see the marine
layer start to return Saturday or Sunday, but confidence is low on
when that occurs. If there is no major synoptic change, temperatures
could also trend warmer for Friday and Saturday. &&
.AVIATION...
(18Z TAFS)
Issued at 1155 AM PDT Mon Jun 8 2026
VFR through the afternoon as high level clouds begin to move across
the region as the low pressure system to our northwest moves
onshore. MVFR ceilings begin to fill in at terminals beginning as
early as 5pm PDT today and will be widespread by sunset. Moderate
westerly winds (10+ kts) prevail through the afternoon and early
evening with embedded gusts in excess of 20kts. Medium to high
confidence that most terminals will develop IFR ceilings overnight,
except for LVK and SJC where it will remain MVFR through Tuesday
morning. Winds ease overnight and may become variable at times at
some sites, but will predominantly come from the west unless
otherwise stated in TAF. North Bay and coastal terminals have a 20-
30% chance of experiencing some drizzle (up to 0.01 inches) this
evening through the overnight hours from the approaching upper-level
trough, though confidence is currently too low to include in the TAF.
Vicinity of SFO...VFR and strong gusts prevail through the day into
the evening. MVFR ceilings will settle over the Bay around 5pm as
westerly winds begin to ease. Ceilings will become borderline IFR-
MVFR around sunset time and eventually get pushed to IFR through the
overnight hours. Conditions improve back to VFR by late Tuesday
morning due to mixing. High confidence in forecast.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR through the afternoon as westerly winds
increase to moderate breezes (10-15kts). Winds diminish slightly
early evening (~5pm PDT) with developing MVFR ceilings that
eventually become IFR through the overnight hours. Expecting
conditions to transition back to VFR by Tuesday morning.
&&
.AVIATION...
(00Z TAFS)
Issued at 545 PM PDT Mon Jun 8 2026
A trough and cold front are building into the region, pushing mid
and low level clouds from the northwest to the southeast. MVFR and
IFR CIGs are building along the coast with the rest of the TAF sites
filling into the evening. Winds reduce into the evening becoming
light to moderate. Drizzle and light rain will be possible overnight
in the far northern portions of the North Bay, as well as along the
coast, affecting visibilities. Cloud cover begins to erode in the
mid morning with widespread VFR expected Tuesday afternoon with
moderate to breezy winds.
Vicinity of SFO...Strong west winds with gusts up to 35 kts last
into the evening before reducing as MVFR and IFR CIGs continue to
build. CIGs erode into the the late morning with breezy to gusty
winds arriving into the afternoon as skies continue to clear. These
winds ease again into Tuesday night.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...MVFR CIGs lower to IFR levels into the
night as winds weaken. Cloud cover begins to lift and erode in the
mid morning, with VFR expected by the late morning. Expect breezy
west and northwest winds to arrive into Tuesday afternoon.
&&
.MARINE...
(Tonight through next Saturday)
Issued at 320 PM PDT Mon Jun 8 2026
Gale force winds continue to affect the inner waters sound of
point sure, with the southern outer waters still seeing gusty
winds while the rest of the area is seeing winds and seas ease.
Expect winds to ease across the waters overnight, but
northwesterly wind and seas will begin to build again Tuesday
morning, Hazardous conditions for small craft develop by mid-
morning across the coastal waters. Gale force wind gusts are
possible by early Wednesday morning over the outer waters. Winds
and seas begin to ease again into Thursday, and stay light
through the weekend.
&&
.FIRE WEATHER...
Issued at 545 PM PDT Mon Jun 8 2026
Hot temperatures, gusty north winds, and low humidities across the
North Bay interior mountains will raise the fire weather threats
late on Wednesday into Thursday, with a particular emphasis on the
interior mountains of Napa County. Although the strongest winds will
remain within the Sacramento Valley, gusts of 25 to 35 mph are
expected to spread into Napa County, with stronger gusts of 40-50
mph possible along the Vaca Mountains along the county's eastern
edge. Meanwhile, daytime humidity retention will be very poor with
relative humidity values as low as 10-15%, while overnight
recoveries are likewise poor as RH values top out at 20-30%. Thus,
fuels are expected to dry rapidly, leading to the elevated fire
weather concerns. It's a little too early to put out fire weather
products at this stage, but this will be re-evaluated today and
Tuesday as the dry conditions approach. Elsewhere across the
district, conditions remain hot and dry, but we're not expecting
winds to be as strong as they are across the interior North Bay.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 9 PM PDT Tuesday for Mry Bay.
Small Craft Advisory from 9 AM Tuesday to 9 PM PDT Wednesday for
Pigeon Pt to Pt Pinos 0-10 nm-Pigeon Pt to Pt Pinos 10-60
NM-Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras
Blancas 0-10 nm-Pt Reyes to Pigeon Pt 0-10 nm.
Gale Warning until 9 PM PDT this evening for Pt Pinos to Pt
Piedras Blancas 0-10 nm.
Small Craft Advisory from 9 AM Tuesday to 3 AM PDT Wednesday for
Pt Arena to Pt Reyes 10-60 NM.
Gale Warning from 3 AM to 9 PM PDT Wednesday for Pt Arena to Pt
Reyes 10-60 NM.
&&
$$
SHORT TERM...KR
LONG TERM....KR
AVIATION...Murdock
MARINE...Murdock
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Prepared by Boulder-Creek.com Weather at: Mon Jun 8 18:30:02 PDT 2026
From the National Weather Service
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