864
FXUS66 KMTR 162157
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
257 PM PDT Sun Jun 16 2024

...New SYNOPSIS, SHORT TERM, LONG TERM, FIRE WEATHER...

.SYNOPSIS...
Issued at 124 PM PDT Sun Jun 16 2024

Red Flag Warning has been issued for the North Bay Interior
Mountains from 11 AM to 8 PM Monday. Dry and breezy conditions
continue into Monday night. Better onshore flow and moisture
return by midweek. Another warming trend on the way for the
upcoming weekend.

&&

.SHORT TERM...
(This evening through Monday)
Issued at 124 PM PDT Sun Jun 16 2024

Visible satellite showing mostly clear skies across the area aside
from some high clouds over northern portions of the CWA. This is
in response to the trough moving into the western US that is
ultimately responsible for our current windy conditions. These
conditions are expected to last through Monday night. As such, a
Red Flag Warning was issued in effect from 11 AM to 8 PM Monday
for interior high elevation portions of the North Bay. This is a
marginal case for Red Flag, but the decision was ultimately driven
by RH as low as 10% - potentially single digits - and gusty winds
to 30 mph as well as limited RH recovery Monday night going into
Tuesday morning. These conditions appear to be fairly limited to
interior Napa county above about 1,000 feet. Elevated fire weather
concerns continue to exist elsewhere, but other locations won`t
see RH values as critical as interior Napa and will have better
overnight RH recovery. Otherwise, Monday looks like a fairly
pleasant day with highs in the 70s to lower 80s.

&&

.LONG TERM...
(Tuesday through next Saturday)
Issued at 124 PM PDT Sun Jun 16 2024

For the rest of the week, the main upper low moves out into the
northern plains while a weak trough pattern remains but slowly
degrades. Not much change in sensible weather through midweek as a
result. A warming trend kicks off late in the week as 500mb
heights continue to rise. Cluster guidance and ensemble guidance
generally support this pattern with a broad ridge building across
the west. Still looking into the D6-7 range here, but the coming
weekend will be something to keep an eye on regarding elevated
HeatRisk for inland areas.

&&

.AVIATION...
(18Z TAFS)
Issued at 1116 AM PDT Sun Jun 16 2024

VFR through the TAF period with strong, gusty westerly winds
beginning this afternoon and continuing into Sunday night. Stratus
is expected to stay offshore with only high level clouds moving over
the region tonight. Gusts between 25 to 30 knots are possible across
the Bay Area and Central Coast today. Locally higher gusts are
possible at OAK and SFO which are expected to see gusts between 30
to 37 knots. Forecast vertical wind profiles suggest low level winds
(below 3,000 feet) between 30 to 40 knots will continue through 06Z
to 07Z after which winds will weaken in the lower levels and at the
surface. Breezy to gusty conditions return tomorrow but gusts are
not currently expected to be as strong as those forecast today.

Vicinity of SFO...VFR through the TAF period with strong, gusty
westerly winds through tonight. Gusts between 30 to 37 knots are
currently expected with some ensemble guidance suggesting that gusts
up to 40 knots are possible. Confidence is high that gusts over 35
knots will develop as stronger low level winds (between 30 to 40
knots) mix down to the surface. Current timing for stronger gusts is
from 21Z to 07Z to account for when low level winds begin to
strengthen and decrease. Surface winds will weaken, becoming more
moderate, after 07Z as low level winds drop off before breezier
conditions return tomorrow afternoon.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR through the TAF period with gusty west
to northwest winds starting this afternoon and continuing into the
evening. Westerly winds will weaken by the late evening with light
to moderate winds expected overnight. Currently not expecting CIGs
to develop at either MRY or SNS tonight but a few models suggested
some lower level clouds could develop at MRY. However, confidence
was too low to include in MRY TAF so will continue to monitor.

&&

.MARINE...
(Today through Friday)
Issued at 1116 AM PDT Sun Jun 16 2024

Widespread gale force to at times high end gale force gusts
continue into early Monday before diminishing in areal coverage
and intensity.Conditions dangerous to small crafts over the
coastal waters persists through, at minimum, midweek as
widespread strong to near gale force gusts continue over the
waters beginning early Monday. Significant wave heights will peak
between 12 to 14 feet Sunday into Monday before gradually
diminishing to 8 to 11 feet by mid- week. Hazardous conditions
over the coastal waters continue through the work week.

&&

.FIRE WEATHER...
Issued at 124 PM PDT Sun Jun 16 2024

...Elevated Fire Weather Conditions Through The Weekend...

*Breezy to gusty northerly winds, especially higher terrain
*Lowering relative humidity values day and night

Much of the detail regarding the Red Flag Warning for the interior
North Bay mountains is outlined in the SHORT TERM section.
Elevated fire weather conditions continue area-wide through
Monday. We continue to see small vegetation and grass fires today,
showing that fine fuels are very susceptible. Better moisture
return enters the picture by midweek, though dry afternoons
persist.

Behringer

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...Red Flag Warning from 11 AM to 8 PM PDT Monday for CAZ504.

PZ...Small Craft Advisory until 3 AM PDT Monday for SF Bay N of Bay
     Bridge.

     Small Craft Advisory until 3 AM PDT Monday for Mry Bay.

     Gale Warning until 3 AM PDT Monday for Pigeon Pt to Pt Pinos 0-
     10 nm-Pigeon Pt to Pt Pinos 10-60 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.

&&

$$

SHORT TERM...Behringer
LONG TERM....Behringer
AVIATION...Kennedy
MARINE...Kennedy

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