FXUS66 KMTR 282317
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
417 PM PDT Sat Mar 28 2026
...New AVIATION, MARINE...
.KEY MESSAGES...
Updated at 1212 PM PDT Sat Mar 28 2026
- Above normal temperatures over the weekend
- Cooler conditions return Monday with beneficial, light rain
Tuesday through Thursday
&&
.SHORT TERM...
Issued at 1212 PM PDT Sat Mar 28 2026
(This evening through Sunday)
The 12Z sounding observed an 850 millibar temperature of 14.15
degrees Celsius which is above the 90th percentile (13.5 degrees
Celsius) for the date and time. This warm air mass will result in
above normal temperatures that will contend with daily high
temperature records this weekend. Stratus that was advected via a
southerly surge is beginning to pull back to the coast where it is
expected to stay throughout the day. The shallow marine layer of 500
feet will likely undergo further compression as southerly flow veers
to become northerly, promoting dry northerly flow. Stratus and
patchy fog is expected to return to coastal locations tonight.
&&
.LONG TERM...
Issued at 1212 PM PDT Sat Mar 28 2026
(Sunday night through next Friday)
A passing upper-level shortwave trough and its associated dying cold
front will encroach from the northwest Monday. This will crack the
storm door open. Unfortunately, we will be far removed from the
parent system in the Northern Great Plains; thus, only cooler
conditions and wind are expected in the absence of rainfall. A gale
force low pressure system in the Gulf of Alaska will head towards
the Pacific Northwest on Tuesday. As it does so, it will pull in
tropical moisture from the Northwestern Pacific Ocean that will
overtop strong high pressure centered in the Northern Pacific Ocean.
The strength of the aforementioned low will allow it to cut through
the aforementioned high, renewing our chances for rainfall. The
associated cold front will pass Wednesday into Thursday, bringing
beneficial, light rainfall to the North Bay and locations along the
bayshore and Pacific Coast. Interior higher terrain may get
measurable rainfall with the help of orographic lift, otherwise the
interior will remain dry. To put the month of March's precipitation
into context we'll use San Francisco Downtown as an example. It has
not rained there since March 2nd. If it rains on Tuesday, it'll tie
1923 for the longest dry stretch in March. 1923 is the driest March
on record with 0.03", 2026 is the second driest on record so far
with 0.06". Surface high pressure will nose in from the Eastern
Pacific Ocean on Friday, rebounding temperatures near to slightly
above normal.
&&
.AVIATION...
(00Z TAFS)
Issued at 417 PM PDT Sat Mar 28 2026
VFR with some high clouds across the region. Gentle to moderate
onshore winds prevail through the afternoon and evening with a weak
offshore component persisting in the far interior regions. A shallow
marine layer results in a moderate confidence for IFR-LIFR stratus
overnight across the immediate coastal region, with patchy fog
possible, especially at HAF. At STS, low probability and confidence
for LIFR-IFR conditions early Sunday morning. Elsewhere, VFR
conditions prevail with light winds through Sunday morning, with
breezy onshore flow resuming in the afternoon.
Vicinity of SFO... VFR with thin high clouds through the TAF period.
Gentle to moderate west-northwest winds continue through the evening
hours. Winds gradually diminish in the late evening with light winds
Sunday morning, before the breezy west-northwest winds resume during
the afternoon. Very low probabilities of stratus impacts to the
terminal, with the bulk of the impacts to the east closer to OAK and
SJC. This is still a low probability forecast, and could be moot if
the marine layer is compressed enough to prevent stratus from
flowing through the Golden Gate.
SFO Bridge Approach... Low confidence for stratus impacts to the
approach path, conditional on stratus making it through the
Golden Gate. Otherwise, similar to SFO.
Monterey Bay Terminals... VFR conditions at present with gentle
northwest winds through the evening hours. This evening, IFR-LIFR
stratus will move into the terminal region, with the return expected
later this evening through the early part of Sunday morning.
However, there is low confidence on how long the ceilings will last,
with a compressing marine layer resulting in the possibility of the
stratus dissipating early, especially at MRY where some offshore
flow could contribute to clearing. In any case, the stratus should
clear by the late morning and early afternoon hours with breezy
northwest winds resuming.
&&
.MARINE...
(Tonight through next Thursday)
Issued at 417 PM PDT Sat Mar 28 2026
Hazardous conditions for small craft continue across the northern
outer waters due to moderate to fresh northerly breezes. This
will spread into the inner waters and the rest of the outer waters
tomorrow where infrequent strong gusts are expected. Moderate
northwesterly breezes on Tuesday will back to become southerly by
Wednesday. Light rain returns Tuesday. Moderate seas will
prevail.
&&
.CLIMATE...
Issued at 717 AM PDT Sat Mar 28 2026
Here are the record high temperatures at the long term sites for
March 28th and March 29th.
Location March 28th March 29th
Santa Rosa 85 in 1923 86 in 2018
San Rafael 81 in 2018 85 in 2018
Kentfield 91 in 1923 84 in 1935
Napa 83 in 2015 83 in 2018, 1968
Richmond 81 in 1969 79 in 1968
Livermore 82 in 2015 85 in 2015
San Francisco 81 in 1986 81 in 2018
SFO Airport 77 in 2018 81 in 2018
Redwood City 81 in 2018 85 in 2018, 1968
Half Moon Bay 79 in 1968 77 in 2004
Oakland 79 in 2015 79 in 2003
San Jose 84 in 1923 82 in 2018
Salinas Airport 84 in 2004 86 in 2018
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM to 9 PM PDT Sunday for Pt Arena
to Pt Reyes 0-10 nm.
Small Craft Advisory until 9 PM PDT Sunday for Pt Arena to Pt
Reyes 10-60 NM.
&&
$$
SHORT TERM...Sarment
LONG TERM....Sarment
AVIATION...DialH
MARINE...Sarment
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Prepared by Boulder-Creek.com Weather at: Sat Mar 28 20:30:02 PDT 2026
From the National Weather Service
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