011
FXUS66 KMTR 170403
AFDMTR

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

...New UPDATE...

.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.

&&

.UPDATE...
Issued at 859 PM PDT Sun Jun 16 2024

First and foremost we continue to monitor a heat signature on
GOES West, which is associated with the Point Fire near Lake
Sonoma. Current transport flow is from NW to SE, which is taking
associated smoke over Santa Rosa, Windsor, Sonoma, and Napa to
name a few. Closer to the fire itself surface winds are prevailing
from the NW as well with gusts 15-20 mph. Winds will remain NW,
but ease up a little overnight. Thankfully, easing winds will be
followed by moderate humidity recovery tonight.

Otherwise, it was a pleasant day around the Bay Area and Central
Coast. Despite ample sunshine temperatures topped out a few
degrees below seasonal averages for mid-June. Did see a few far
interior locations reach the upper 80s to mid 90s. It was also
another breezy to locally gusty day around the region too. The N-S
gradient may have eased, but onshore flow (W-E) remains strong
which helped support the stronger winds. Winds gusted generally
25-40 mph, with KSFO gusting to 53 mph.

No update needed this evening, but will fine tune the forecast
overnight for the ongoing wildfire in Sonoma county and the Red
Flag conditions for Monday across the interior North Bay
Mountains.

MM

&&

.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...
(00Z TAFS)
Issued at 445 PM PDT Sun Jun 16 2024

Clear skies throughout our region with North Bay terminals
experience a bit of haze and smoke from fires in the county. Flight
category still remains VFR and is expected to prevail through the
TAF period for all terminals. The only aviation concerns will be
strong gusty wind this evening. Winds will be predominately
westerly/northwesterly and will remain onshore through the TAF
period. Winds diminish overnight for most terminals but will
remain relatively moderate to breezy for most terminals. Gusty
strong winds will return Monday afternoon with chances of gust up
to 25-30 knots.

Vicinity of SFO...High confidence of VFR through the TAF period.
Gusty onshore winds will prevail until early morning where winds
will diminish briefly before rebuilding Monday late morning.
Currently observation show gusty winds up to 40 knots. Therefore,
AWW was issued through 07Z.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...VFR continue to prevail through the TAF
period. Westerly to northwesterly winds gusty winds continuing into
the evening and will transition to light to moderate winds
overnight. Possible few to scattered low clouds may develop
overnight but not anticipated to become MVFR.

&&

.MARINE...
(Tonight through next Friday)
Issued at 445 PM PDT Sun Jun 16 2024

Widespread gale force gusts continue before diminishing in areal
coverage and intensity late Sunday night. By early Monday, gale
force gusts will have weakened to strong to near gale force with
widespread conditions dangerous to small crafts persisting
through mid-week. 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 will persist through
the late work week with strong gusts expected to continue over the
majority of the coastal waters.

&&

.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 Mry Bay-SF Bay N
     of Bay Bridge.

     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...SO
MARINE...Kennedy

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