Mount Hamilton, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

190
FXUS66 KMTR 220505
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1005 PM PDT Sat Jun 21 2025

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 219 PM PDT Sat Jun 21 2025

Fire concerns linger for today and tonight, but ease as winds
reduce into Sunday. Expect a modest warming trend for the more
inland areas into the next work week along with a return of
coastal clouds and fog.

&&

.SHORT TERM...
(This evening through Sunday)
Issued at 219 PM PDT Sat Jun 21 2025

Winds are building into the afternoon. However, the updated forecast
is showing that the widespread wides are going to be weaker overall
than the winds experienced yesterday, with only a few exceptions
along the immediate coast. Temperatures are mostly around average
today as the onshore flow continues and today looks to be the
coolest of the next seven. Winds over land reduce into the evening
and early tonight, but will stay gusty within the marine
environment.

The reduction of winds tonight marks the end of our breezy to gusty
pattern and pulls the interior areas out of near critical fire
danger. However, a lot of the finer fire fuels (grasses and small
plants) have dried and cured in the last few days of dry, sunny and
windy conditions, so we urge folks to stay fire weather aware.

&&

.LONG TERM...
(Sunday night through next Friday)
Issued at 219 PM PDT Sat Jun 21 2025

Winds have been the big focus of the forecast over the last few
days, but as the upper level pattern changes, the breezy and gusty
conditions are mostly going to be focused over the marine
environment into the next work week.

Said change in the upper level pattern with feature the upper level
pushing east and slightly south. This will reduce onshore flow into
the mid week and weaken winds across the region. Temperatures will
increase in the far interior, while the coast and slightly inland
areas stay mostly unchanged as marine stratus and fog begin to
reestablish in the calmer conditions. As of the current forecast,
Thursday looks to be the warmest day of the forecast as the more
interior valleys settle into the 90s and some of the warmest of the
warm hitting the 100 degree mark, but this won`t be widespread and
the coastal and slightly inland areas remain in the 60s and 70s.

Something to note, the mid-week model agreement is fair with the
current official forecast, but some models hint at the trough pushing
farther south and propagate in such a way that could introduce more
offshore flow. This will still result in the midweek warm up, but
the drier flow could limit the marine layer and coastal cloud cover,
making for a much warmer days for the coast. The forecasting team
will be keeping an eye on how this continues to develop over the
next few forecast updates, be sure to keep checking back in!

&&

.AVIATION...
(06Z TAFS)
Issued at 1004 PM PDT Sat Jun 21 2025

VFR through the TAF period. Confidence is low that stratus will
reach HAF, MRY, and SNS overnight with high resolution HRRR guidance
supporting these sites staying clear overnight. Other models (LAMP)
show patchy stratus developing and bringing in local IFR-MVFR
conditions to these sites. Leaned more towards HRRR output with
drier land conditions and strong northerly winds over the ocean
helping to decrease chances for widespread stratus formation. Winds
have largely eased across the area with only locally breezy
conditions continuing along the coast and where terrain funneling is
favored. Northwesterly winds pick up again during the day tomorrow
but gusts will only peak between 20 to 25 knots. Initial guidance is
indicating some potential for stratus to return along the coast
around 03-06Z but confidence is low.

Vicinity of SFO...VFR. Winds have started to ease at SFO with gusts
continuing to trend downwards overnight. Northwesterly winds pick up
again during the afternoon tomorrow with gusts to peak around 25
knots. Guidance indicates some potential for stratus to reach SFO
around 09-12Z tomorrow night with chances increasing after 09Z.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR with low potential for IFR-MVFR CIGs to
develop overnight. HRRR guidance keeps conditions clear at MRY and
SNS while NBM and LAMP guidance suggest stratus could fill in
overnight. Leaning more towards conditions staying clear overnight
but if ceilings do develop, they are most likely to develop between
10-15Z. Guidance is indicating some potential for stratus to return
late tomorrow evening through the end of the TAF period but
confidence is low

&&

.MARINE...
(Tonight through next Friday)
Issued at 1004 PM PDT Sat Jun 21 2025

Widespread hazardous marine conditions continue through early
Saturday morning with northerly near gale force to severe gale
force  gusts across the coastal waters. Rough to very rough seas
persist  through Sunday with elevated wave heights between 10 to
13 ft. Winds  subside to fresh to strong and shift northwesterly
Sunday. Patchy  gale force winds remain possible in the coastal
jet regions from  Point Arena to Point Reyes and Point Pinos to
Point Piedras Blancas  Sunday afternoon. Seas begin to abate
Sunday into early next week  with moderate to rough seas
persisting through the end of the next  work week.

&&

.FIRE WEATHER...
Issued at 221 PM PDT Sat Jun 21 2025

Elevated to near critical fire weather conditions continue today
across the interior Central Coast, East Bay Hills, and interior
North Bay as another dry day with moderate to poor RH recovery is
expected for interior locations and areas of higher elevation,
especially for those above the marine layer. Winds will be breezy
to gusty as well, peaking around 35 mph, perhaps locally higher
at exposed elevations and wind prone gaps. Breezy to gusty winds
look to hold through Saturday night. There should be some
improvement in humidity into Sunday morning, especially if the
marine layer is able to deepen. Widespread critical fire weather
conditions are not expected within the district today, although
the fire weather threat will increase once again for areas closer
to the Central Valley. The fire weather threat will continue to
diminish Sunday into the early part of next week with the gusty
winds further relaxing, although humidity values in the interior
will be slow to rise.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Coastal Flood Advisory from 6 PM Sunday to midnight PDT Sunday
     night for CAZ006-506-508.

PZ...Small Craft Advisory until 3 AM PDT Sunday for Mry Bay-SF Bay N
     of Bay Bridge.

     Small Craft Advisory from 3 PM to 9 PM PDT Sunday for Mry Bay.

     Gale Warning until 3 AM PDT Sunday for Pigeon Pt to Pt Pinos 0-
     10 nm-Pt Arena to Pt Reyes 0-10 nm-Pt Arena to Pt Reyes 10-
     60 NM-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt Reyes to
     Pigeon Pt 0-10 nm.

     Gale Warning until 9 AM PDT Sunday for Pigeon Pt to Pt Pinos 10-
     60 NM.

&&

$$

SHORT TERM...Murdock
LONG TERM....Murdock
AVIATION...Kennedy
MARINE...Kennedy

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