FXUS66 KMTR 130424
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
923 PM PDT Thu Mar 12 2026
...New AVIATION...
.KEY MESSAGES...
Updated at 238 PM PDT Thu Mar 12 2026
- Above normal temperatures and Minor HeatRisk through Saturday
- Well above normal temperatures and areas of Moderate HeatRisk
Sunday through the extended forecast
- Elevated potential for grass fires next week as drier and
warmer conditions continue
&&
.UPDATE...
Issued at 845 PM PDT Thu Mar 12 2026
Clear conditions prevail across the region, with scattered high
clouds across the Bay Area and some evidence of stratus formation
near Point Reyes and just off the Sonoma County coast. The Bodega
bay profiler is hinting at a rather shallow marine layer, around
500-1000 feet deep, and high resolution model output is hinting at
some stratus development at the immediate coast through the night.
The operations team will monitor the stratus evolution, or lack
thereof, through the night.
DialH
&&
.SHORT TERM...
Issued at 238 PM PDT Thu Mar 12 2026
(This evening through Friday)
No major adjustments to the short term forecast. Upper level ridging
and high pressure continue to push in along the West Coast with
temperatures running 10 to 15 degrees above normal. A glance at the
current 1PM observations shows that temperatures are running
anywhere from 5 to 10 degrees warmer than they were at this time
yesterday. High temperatures today will largely be in the upper 70s
to low 80s with coastal locations staying in the 60s to 70s. Minor
HeatRisk is expected today across almost the entire CWA. This
primarily effects those who are extremely sensitive to heat and lack
adequate access to cooling or hydration. If you are working outside
or are sensitive to the heat, make sure that you are taking breaks
and are drinking plenty of water. San Jose remains the only site
forecast to tie their daily record today with a forecast high of 81
degrees. As of 1PM, SJC is reporting a temperature of 71 degrees
with several hours of heating to go this afternoon. Temperatures do
cool down overnight with lower elevations dropping into the 40s
while higher elevations stay in the 50s. This will bring overnight
relief from the heat and allow people to cool down.
&&
.LONG TERM...
Issued at 238 PM PDT Thu Mar 12 2026
(Friday night through next Wednesday)
A long duration heat event will continue through the extended
forecast as upper level ridging and high pressure linger over
California. The Long Term forecast can be split into two main
distinctions: when onshore flow is present and when offshore flow is
present. Winds are predominantly onshore Friday and Saturday before
shifting offshore Sunday through the remainder of the extended
forecast. Onshore winds will help to mitigate how much temperatures
warm Friday and Saturday. This will keep temperatures in the upper
70s to low 80s across the interior and 60s to 70s along the coast.
It is worth pointing out that although this is comparatively cooler
than what we will see later in the week this is still 10 to 15
degrees warmer than normal for this time of year.
As we head into Sunday, the center of the upper level ridge will be
just offshore of the Bay Area and supports winds shifting offshore.
This transition is important as it will bring drier, warmer
continental air into the region and support further temperature
rises. This will allow many of our climate sites (see Climate
section below for a list of sites) to either challenge or break
their daily temperature records next week. Temperatures across the
interior will climb into the upper 80s to low 90s as early as Sunday
before becoming more widespread Monday and Tuesday. There is the
potential for records to be broken daily Sunday through Wednesday
but the locations do vary. Noteworthy spots to watch would be San
Jose and the Salinas Airport as both sites are forecast to break
their daily records Monday and Tuesday. More coastal sites (San
Francisco, Half Moon Bay) may come close to their records but are
not currently forecast to break them. At the same time, morning low
temperatures also warm next week with lows rising into the mid to
upper 50s. This will limit overnight relief from warm temperatures
and is a key factor in the return of Moderate HeatRisk Monday and
Tuesday. This is our first major heat event of the year and our
bodies are still used to comparatively cooler winter weather. It is
important to stay hydrated and allow time for rest if participating
in outdoor activities on Monday/Tuesday. The current forecast shows
temperatures remaining hot at least through Wednesday but likely
through Friday.
Another concern with the return of warmer, drier conditions and
light offshore winds next week is the potential for small
fires/grass fires. Larger fuels are still moist from winter rains
but the return of much above normal, hot weather may result in
smaller fine fuels (grass) curing faster than normal. Winds are
expected to be relatively light which will minimize how much any
grass fires that are able to develop can spread. This is primarily
important for Prescribed Burns but if you are participating in any
outdoor activities for spring break (i.e. camping, hiking,
offroading, etc.) make sure to take this into account as well.
&&
.AVIATION...
(06Z TAFS)
Issued at 923 PM PDT Thu Mar 12 2026
VFR continues this evening. 5.0 mb ACV-SFO, 2.6 mb SFO-SMX and 1.5
mb SFO-SAC pressure gradients support ongoing northwest winds.
Conditions have improved over the last week for potential night-time
and morning coastal stratus/fog; satellite shows the leading edge of
stratus moving southward passing by Point Reyes. 06z KHAF, KOAK and
KMRY TAFs advertise stratus LIFR-IFR ceilings tonight and Friday
morning. Inland terminals continue with VFR. High clouds are
forecast to increase during the 06z TAFs otherwise coastal
stratus/fog is likely to mix out by late Friday morning.
Vicinity of SFO...VFR. West wind near 15 knots decreasing to 5 to
10 knots tonight then increasing to near 15 knots Friday afternoon
and evening.
SFO Bridge Approach...Similar to SFO.
Monterey Bay Terminals...VFR through mid to late evening, then
increasing probability of patchy stratus and/or fog. Conditions
improving to VFR by late Friday morning. Stratus /IFR/ returns
Friday night and Saturday morning. Northwest winds near 10 knots
decreasing and becoming light southeast tonight and Friday morning.
Winds westerly near 10 knots Friday afternoon and early evening.
&&
.MARINE...
(Tonight through next Wednesday)
Issued at 845 PM PDT Thu Mar 12 2026
Gusty northwesterly winds continue across the waters. Winds will
eventually increase for the near shore zones by late Friday. The
stronger winds will result in locally hazardous conditions. Winds
and seas ease into the next work week.
&&
.CLIMATE...
Issued at 614 PM PDT Thu Mar 12 2026
The following are the record high temperatures at the long term
sites for March 15th, 16th, 17th and 18th.
Location Mar 15 Mar 16 Mar 17 Mar 18
Santa Rosa 88 in 2004 91 in 2004 87 in 1996 84 in 2010
San Rafael 83 in 1972 87 in 1972 84 in 1972 80 in 1996
Kentfield 85 in 2004 86 in 2004 87 in 1914 89 in 1914
Napa 86 in 2004 88 in 2004 92 in 1914 87 in 1914
Richmond 85 in 2004 84 in 1972 83 in 2004 78 in 1996
Livermore 83 in 1972 88 in 1972 87 in 1972 86 in 2004
San Francisco 82 in 2004 85 in 1914 85 in 1914 86 in 1914
SFO Airport 81 in 2004 82 in 2004 82 in 2004 77 in 2004
Redwood City 84 in 2004 84 in 2004 85 in 2004 84 in 2004
Half Moon Bay 74 in 1974 78 in 1972 83 in 2004 75 in 1978
Oakland Museum 85 in 2004 85 in 2004 85 in 2004 81 in 2004
San Jose 82 in 2004 85 in 1914 88 in 1914 87 in 1914
Salinas Airport 83 in 1972 87 in 2004 87 in 2004 84 in 1960
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 9 AM Friday to 3 AM PDT Saturday for
Pt Arena to Pt Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas
0-10 nm.
Small Craft Advisory from 3 PM Friday to 3 AM PDT Saturday for
Pt Reyes to Pigeon Pt 0-10 nm.
Small Craft Advisory from 9 PM Friday to 3 AM PDT Saturday for
Pigeon Pt to Pt Pinos 0-10 nm.
Small Craft Advisory until 3 AM PDT Saturday for Pigeon Pt to Pt
Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...Kennedy
LONG TERM....Kennedy
AVIATION...Canepa
MARINE...Canepa
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Prepared by Boulder-Creek.com Weather at: Fri Mar 13 00:30:02 PDT 2026
From the National Weather Service
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