FXUS66 KMTR 151725
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
1025 AM PDT Sun Jun 15 2025
...New AVIATION, MARINE...
.SYNOPSIS...
Issued at 115 PM PDT Sat Jun 14 2025
Cool and calm conditions prevail. Warm temperatures inland, but
still near seasonal normals. Slight warming trend inland mid next
week. Dry conditions persist across high terrain, leading to
elevated grass fire danger.
&&
.SHORT TERM...
(Today and tonight)
Issued at 327 AM PDT Sun Jun 15 2025
No significant change to the forecast, with persistence carrying
through at least today into early Monday before a subtle pattern
change takes shape in the form of a slightly deepening trough
approaching from the west Monday afternoon. Weak shortwave H50 rises
today out ahead of the approaching trough will result in another
respite of June Gloom for most locations with patchy low stratus
lingering across the San Mateo coastline into the Bay area this
afternoon. With the steadier, increasing fetch of onshore flow
getting closer late tonight we'll see more widespread marine layer
stratus develop by early Monday morning.
&&
.LONG TERM...
(Monday through Saturday)
Issued at 327 AM PDT Sun Jun 15 2025
The aforementioned subtle pattern change will see shortwave ridging
on the backside of the weak trough passing across our area Monday,
helping to lift temperatures on Tuesday and Wednesday slightly above
normal. The brief warm up will through the middle of the week will
see temperatures return to mostly normal for the end of the week as
another trough is positioned to our west. A secondary, deeper and
sharper trough next weekend may bring gusty winds and a potential
increase in fire (grassland) weather concerns through the remainder
of the extended forecast.
&&
.AVIATION...
(18Z TAFS)
Issued at 1024 AM PDT Sun Jun 15 2025
VFR conditions are returning to the region, with the exception of
HAF where MVFR ceilings persist and may linger through the day. West-
northwesterly winds will increase this afternoon easing late this
evening and into Monday morning. Moderate to high confidence for
IFR/MVFR ceilings to develop over the Monterey Bay terminals early
Monday morning. However, confidence is low to moderate for IFR/MVFR
ceilings to develop over the San Francisco Bay terminals early
Monday morning. Any low clouds that do develop are expected to
gradually lift and scatter out by mid-to-late Monday morning.
Onshore winds will be stronger Monday afternoon as the pressure
gradient tightens.
Vicinity of SFO...VFR. High confidence for westerly winds to
increase this afternoon with VFR conditions anticpated to prevail
through the evening. Winds ease a bit overnight, but generally are
expected to remain out of the west-northwest. Low to moderate for
IFR/MVFR ceilings to develop early Monday morning, yet any low
clouds that do develop are likely to mix out by around 18Z Monday.
Have stronger onshore winds in toward the end of the TAF period with
gusts at SFO forecast to be up to 32 kt Monday afternoon.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR. Onshore winds increased this afternoon
before easing late this evening and into Monday morning. Moderate to
high confidence for IFR/MVFR ceilings to develop early Monday
morning. These low clouds will begin to lift by late Monday morning
before scattering out for the afternoon.
&&
.MARINE...
(Today through Friday)
Issued at 1024 AM PDT Sun Jun 15 2025
Surface high pressure will support a fresh to strong
northwesterly breezes with moderate seas through mid-week. Gale
force gusts are likely near the coastal jet regions of Point Reyes
and Point Sur. An eastward passing upper level trough combining
with a strengthening onshore pressure gradient will result in
gusty onshore winds across the bays Monday afternoon and evening.
&&
.FIRE WEATHER...
Issued at 556 PM PDT Sat Jun 14 2025
No real notable changes to the ongoing forecast fire weather wise.
Still highlighting elevated fire weather conditions across the
interior Central Coast. While not in our forecast area, a decent
veg fire developed and spread quickly to over 1k acres in SLO.
This could have easily happened in San Benito or Monterey
counties.
Observations over the last 24 hour and predicted weather continue
to show marine layer influence keeping fire weather conditions in
check for lower elevations and coastal areas. However, about
roughly 2k feet and farther inland conditions remain mild and dry
both day and night. On top of that is onshore flow leading to
breezy conditions each afternoon. Some of the winds are being
enhanced by topography leading to gustier flow in the valleys,
gaps, passes with 20-35 mph gusts.
Simply put, if you're recreating outdoors, be one less spark in
these elevated fire weather conditions.
MM
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM to 9 PM PDT Monday for SF Bay N
of Bay Bridge.
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 Monday to 3 AM PDT Tuesday for
Mry Bay.
Small Craft Advisory until 9 AM PDT Monday for Pt Arena to Pt
Reyes 0-10 nm.
Gale Warning from 9 AM Monday to 3 AM PDT Tuesday for Pt Arena
to Pt Reyes 0-10 nm.
Small Craft Advisory from 3 PM this afternoon to 3 AM PDT
Tuesday for Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory from 9 AM Monday to 3 AM PDT Tuesday for
Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory until 9 PM PDT this evening for Pt Pinos to
Pt Piedras Blancas 0-10 nm.
Gale Warning from 9 PM this evening to 3 AM PDT Tuesday for Pt
Pinos to Pt Piedras Blancas 0-10 nm.
Small Craft Advisory until 3 AM PDT Tuesday for Pigeon Pt to Pt
Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...JM
LONG TERM....JM
AVIATION...RGass
MARINE...RGass
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Prepared by Boulder-Creek.com Weather at: Sun Jun 15 10:30:02 PDT 2025
From the National Weather Service
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