National Weather Service United States Department of Commerce

Critical Fire Weather in the High Plains; Heat Continues in the West

Critical fire weather conditions will persist in the central High Plains through Friday as gusty winds and dry conditions continue. The heat wave across the West and Southwest will continue to intensify through the week, with daily and monthly record highs expected to be broken. Read More >

ZOA CWSU Discussion KSFO TAF TDA
AWAITING CWSU INPUT
TAF TDA

KSFO/KSQL METAR
METAR
Area PIREPs
PIREP
   
Satellite Webcams, Ceiling≤030 Prob
Webcams

Click here to reload map


SIERRA 03 Hour Forecast SIERRA 12 Hour Forecast SIGMETs
TANGO 03 Hour Forecast TANGO 12 Hour Forecast
ZULU 03 Hour Forecast ZULU 12 Hour Forecast
Area Forecast Discussion Forecast Maps

305
FXUS66 KMTR 182342
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
442 PM PDT Wed Mar 18 2026

...New AVIATION, MARINE...

.KEY MESSAGES...
Updated at 1247 PM PDT Wed Mar 18 2026

- Early season, long duration heat wave continues to bring
record- breaking temperatures and Moderate HeatRisk through
Friday

- Elevated potential for grass fires through the week due to
warm and dry conditions with periods of moderate offshore winds

- Gradual cooling trend begins this weekend

&&

.SHORT TERM...
Issued at 1247 PM PDT Wed Mar 18 2026
(This evening through Thursday)

The strong mid/upper level high pressure, that has resulted in
several daily and monthly records the past two days, is currently
over southern California and the Desert Southwest. As forecasted,
the 500 mb height has strengthened to 594 dam with 850 mb
temperatures around 23 degrees C. As such, temperatures this
afternoon will warm into the upper 70s along the immediate coastline
and into the mid 80s elsewhere closer to the coast. Elsewhere, just
inland away from the coast and in the interior, temperatures will
rage from the upper 80s to lower 90s and potentially the mid to
upper 90s the the warmest interior spots. Some locations along the
Sonoma and Marin county coastline remain in the 50s as of early this
afternoon as low stratus and a shallow marine layer impacts that
region.

Tonight into Thursday morning, expecting the coldest interior
locations to cool into the upper 40s (mainly in the North Bay) with
low to upper 50s in other valley locations. In the higher elevations
across the region, we are only expecting mid 60s to lower 70s.

Thursday, we are expecting a degree or two of warming across the
board. Please see the CLIMATE section below for additional details on
potential record breaking heat.

&&

.LONG TERM...
Issued at 121 AM PDT Wed Mar 18 2026
(Thursday through Tuesday)

Rinse and repeat through Friday. Expect record breaking heat each
afternoon as the ridge of high pressure stalls over the desert SW.
Confidence is increasing that the heat wave will start to break on
Saturday. Our latest forecast has temperatures dropping around
10 degrees on Saturday, and another 5 on Sunday. That would bring
us back into the 70s for most inland areas and 60s along the
coast to start next week. By the way, that`s still 5-15 degrees
above normal for this time of year. As the ridge breaks down there
is good chance for stronger winds this weekend, which will bring
some additional relief to the hot temperatures, but also brings some
enhanced fire weather conditions for fine dead fuels. The next
chance for any rain is around the end of the month or early April,
but the ensemble members diverge spectacularly by that point, and
it`s just as likely that another dry heatwave moves in.

&&

.AVIATION...
(00Z TAFS)
Issued at 442 PM PDT Wed Mar 18 2026

No changes to the forecast. Quiet weather continues with onshore
winds occuring near the coast and around the Bay later this
afternoon. This will continue into the evening before winds become
offshore or light and variable overnight. VFR conditions will
prevail, though there could be some pockets of haze.

Vicinity of SFO...Winds have become onshore and will continue
through the evening. Winds may peak at KSFO around 10-15kt before
weakening later this evening. Look for light and variable winds
overnight and into Thursday morning. A similar forecast is expected
tomorrow, with onshore winds returning for the afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Onshore winds are being observed this
afternoon, with winds becoming weakly offshore or variable by the
evening and overnight hours. VFR conditions continue.

&&

.MARINE...
(Tonight through next Monday)
Issued at 442 PM PDT Wed Mar 18 2026

Moderate north to northwest breezes persist across the outer
waters, with gentle breezes over the inner waters. Strengthening
northwest winds begin late Thursday into Friday, and continue into
the weekend. Hazardous seas will likely return to the coastal
waters late this week and weekend.

&&

.CLIMATE...
Issued at 421 AM PDT Wed Mar 18 2026

The following are the record high temperatures at the long term
sites for March 18th, 19th and 20th.

Location Mar 18 Mar 19 Mar 20

Santa Rosa 84 in 2010 83 in 2004 84 in 2004
San Rafael 80 in 1996 81 in 1964 82 in 1960
Kentfield 89 in 1914 83 in 1996 82 in 2001
Napa 87 in 1914 86 in 1914 86 in 2004
Richmond 78 in 1996 80 in 1996 81 in 2004
Livermore 86 in 2004 82 in 2015 87 in 1915
San Francisco 86 in 1914 80 in 2010 78 in 2004
SFO Airport 77 in 2004 78 in 2010 78 in 2004
Redwood City 84 in 2004 81 in 2010 82 in 2004
Half Moon Bay 75 in 1978 79 in 2010 75 in 2010
Oakland Museum 81 in 2004 81 in 1984 78 in 2001
San Jose 87 in 1914 82 in 1988 78 in 2004
Salinas Airport 84 in 1960 87 in 1997 80 in 1934

The following are the record high temperatures at the long term
sites for the entire month of March.

Location

Santa Rosa 91 on March 16, 2004
San Rafael 88 on March 25, 1952
Kentfield 91 on March 28, 1923
Napa 92 on March 17, 1914
Richmond 87 on March 31, 2021
Livermore 90 on March 25 and 26, 2025
San Francisco 87 on March 11, 2005
SFO Airport 85 on March 25, 1952 and March 17, 2026
Redwood City 93 on March 17, 2026
Half Moon Bay 83 on March 31, 2000 and March 17, 2004
Oakland Museum 89 on March 17, 2026
San Jose 89 on March 14, 2015
Salinas Airport 92 on March 14, 2015 and March 17, 2026

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Heat Advisory until 8 PM PDT Friday for CAZ006-502>506-508>510-
512>518-528>530.

PZ...None.
&&

$$

SHORT TERM...RGass
LONG TERM....Flynn
AVIATION...KR
MARINE...KR

Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook, X, and YouTube at:
www.facebook.com/nwsbayarea
x.com/nwsbayarea
www.youtube.com/nwsbayarea




   Select:      24HR Change/Gradients  |  Forecast Gradients   
OSO001
   Select:      MOS/BUFKIT  |  HREF Ceiling  |  WRF RH  |  WRF Ceiling  |  NBM MOS  |  LAMP MOS   






Yesterday ⇛Visible  ⇛Nighttime  ⇛GeoColor+GLM Today
 
24-Hour Temp Change 24-Hour RH Change

⇛Visible  ⇛Nighttime  ⇛GeoColor+GLM

Webcams