Scotts Valley, California Weather Forecast Discussion

130
FXUS66 KMTR 221022
AFDMTR
Area Forecast Discussion
National Weather Service San Francisco CA
322 AM PDT Mon Sep 22 2025
...New SHORT TERM, LONG TERM, MARINE...
.KEY MESSAGES...
Updated at 321 AM PDT Mon Sep 22 2025
- Warming trend continues through Tuesday, areas of Moderate and
   Major HeatRisk
- Weak offshore flow Monday through Tuesday in the higher terrain
- Rain showers and isolated thunderstorm chances return Tuesday
   and lingering through midweek
&&
.SHORT TERM...
Issued at 321 AM PDT Mon Sep 22 2025
(Today and tonight)
Not much going on in the short term forecast as upper level ridging
builds into the region. This will lead to the marine layer
compressing some more, likely keeping stratus confined to coastal
areas and perhaps draining into a portion of the Salinas Valley.
This should quickly mix out by mid to late morning, leading to a
warm fall day. Temperatures today will rise into the up into the mid
80s to mid 90s for interior locations, while those closer to the
coast range from the mid 60s to mid 70s. With ridging holding in
place, a warmer night is on tap with temperatures ranging from the
upper 50s to mid 60s for interior valleys and the coast. For those
in higher elevations, low temperatures span the 60s to low 70s.
&&
.LONG TERM...
Issued at 321 AM PDT Mon Sep 22 2025
(Tuesday through Sunday)
Tuesday will be the warmest day this week, with widespread Moderate
HeatRisk across the Bay Area and smattering portions of the Central
Coast. The latest guidance actually brings Major HeatRisk to the
East Bay counties and even leaks into Santa Clara County. In
addition to that, the cutoff low that looms off west of Baja CA
begins to drift north. The following questions remain with this
system... how fast does it arrive and where does go. The latest
guidance has it tracking towards the Central Coast and tracking into
the Central Valley by mid to late week. Moisture will surge ahead of
it, potentially bringing showers as early as Tuesday afternoon but
more likely occuring late Tuesday into Wednesday. Thunderstorms will
be possible, currently favoring the Central Coast but perhaps
tracking all the way up into the North Bay. Storms should be
sufficient rain makers as PWATs range 1.0-1.4 inches, meaning dry
lightning should be limited.
As the low meanders towards the east on Thursday, conditions begin
to dry out. High temperatures return to near normal for this time of
year and continue into the weekend.
&&
.AVIATION...
(06Z TAFS)
Issued at 945 PM PDT Sun Sep 21 2025
VFR continues as of this writing with VFR probable to be the
dominant flight category at most terminals as overall wind
trajectories will tend to hinder stratus/mist/fog. The exception
will be KHAF and for 1-2 hours potentially KAPC and KOAK.
Confidence is highest that IFR to LIFR ceilings/visibility will
transpire at KHAF, but the timing is uncertain. If stratus does
invade KAPC and KOAK, the most likely timeframe would be just
prior to sunrise Monday. VFR should be the rule at all TAFs by
18Z Monday.
Vicinity of SFO...VFR is advertised, however, we`ll need to
monitor trends upstream across the San Bruno Gap. Current
indications are that stratus may approach the terminal, but the
latest model guidance indicates around a 15-20% chance for
MVFR/IFR cigs. Should stratus make it to the terminal, it`ll
likely be between the 13Z-19Z time frame. For now, I`ll advertise
a scattered deck of clouds around FL015.
SFO Bridge Approach...VAPS may be supported through the entire
TAF cycle and scattered clouds are more probable at the terminal.
Monterey Bay Terminals...A eddy/circulation has formed across
Monterey Bay which has pulled in a little dry air to result in
VFR at KMRY and KSNS. This is anticipated to be relatively short-
lived as satellite trends indicate re-development of IFR to near
LIFR ceilings across northern portions of the bay. Cigs are
forecast to fill back in after 07Z, though confidence in the
exact timing is low. LIFR cigs to intermittent LIFR visibility are
still advertised at KMRY, with IFR cigs at KSNS. VFR is probable
to return after 16Z. There are some indications that marine
stratus will make another run at KMRY and KSNS after 00Z Tuesday,
but have opted for a more optimistic given uncertainty in stratus
re-developing.
&&
.MARINE...
(Today through Saturday)
Issued at 321 AM PDT Mon Sep 22 2025
Breezy to gusty winds linger in the northern outer waters. This
will translate to steep seas, especially for waters near and north
of Point Reyes. Northwesterly swell will continue through the
entire period with wave heights gradually easing. Waters south of
Point Pinos will be prone to 12 to 15 second period southerly
swell, though wave heights will average between 2 and 3 feet.
&&
.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory until 3 PM PDT this afternoon for Pt Arena
     to Pt Reyes 10-60 NM.
&&
$$
SHORT TERM...KR
LONG TERM....KR
AVIATION...Bain
MARINE...Murdock
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NWS MTR Office Area Forecast Discussion