502
FXUS66 KMTR 270535
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco CA
1035 PM PDT Wed Jun 26 2024

...New AVIATION, MARINE...

.SYNOPSIS...
Issued at 1258 PM PDT Wed Jun 26 2024

Near to slightly below normal temperatures persist through
the remainder of the week as troughing settles in. Slight warmup
expected towards the beginning of next week.

&&

.UPDATE...
Issued at 1000 PM PDT Wed Jun 26 2024

The marine layer stratus and fog mixed out by late morning, it`s
been clear since late morning along with areas of gusty onshore
winds through afternoon and early evening. The marine layer depth
varies from approx 800 feet North Bay to 1200 feet north Central
Coast. The ACV-SFO and SFO-SAC pressure gradients prevail this
evening at 4.7 mb and 3.4 mb respectively, resulting in areas of
gusty onshore winds. A band of stratus and fog was seen on evening
satellite imagery to the northwest, high resolution model output
show coastal stratus and fog returning later tonight and Thursday
morning.

Global model forecasts are in good agreement through late week
and the weekend indicating weak 500 mb height troughing over the
forecast area and surface high pressure over the coastal waters
supporting onshore surface winds. Similarly late in the weekend
and early next week there`s agreement at least in the early stages
of strengthening 500 mb heights with a high pressure system 900
to 1000 miles west of the Bay Area, the system potentially moving
eastward reaching our forecast area by the middle of next week.
Recent 12z/00z deterministic output are showing 850 mb temperatures
peaking over our area near 30C to 31C by July 5th and 6th. This
is quite warm even hot at 850 mb level (~5000 feet) if it verified
and would be upper end hot temperatures per comparison of Oakland
upper air soundings for the period of record since 1948. Caveat,
this is still more than a week away, it`s difficult to say whether
or not the global models are overamplifying the pattern beyond 5
days. However, the northern hemispheric pattern is active, zonal
(west to east flowing) jet stream winds across the Pacific and
CONUS have been strong even as of recent, with positive anomalies
in wind strength in mid June 2024 per NOAA daily composites at 200
mb to 300 mb levels, including the 500 mb level. A strong latitudinal
temperature gradient continues to support an energetic north hemispheric
pattern (including across the Pacific no less), with several large
scale low pressure troughs (longwave troughs) composited with maximum
(summer season) solar input/sun angle. Specific to the pattern across
the Pacific and western CONUS this could strengthen the high pressure
system as currently forecast, it`s worth closely monitoring. Stay
tuned to updates.

&&

.SHORT TERM...
(This evening through Thursday)
Issued at 1258 PM PDT Wed Jun 26 2024

Its a beautiful day across the region this afternoon.
Coastal stratus has eroded from the coastline, leaving even the
coast with sunny and clear conditions today. Mid to high level
clouds, remnants of monsoonal moisture, that have traversed the
region in previous days have moved on, leaving us with our typical
summer skies: clear and blue. Troughing settles in today helping to
usher in some cooler temperatures across the region and good onshore
flow. That being said, temperatures will be in the upper 50s and low
60s today and tomorrow, with interior regions seeing high temps in
the low to mid 80s, and regions near bays seeing highs in the mid to
upper 70s. These high temps are anywhere from near normal to around
5 degrees below normal. Overall, pleasant and comfortable for most!
Get out there and enjoy it before or after work if you can!

&&

.LONG TERM...
(Thursday night through next Tuesday)
Issued at 1258 PM PDT Wed Jun 26 2024

These near-normal high temps and overall placid weather
last through the beginning portion of the weekend. Coastal areas may
see the marine layer deepen as troughing continues, and stratus
linger into the late morning. However, towards Sunday, a slight
warmup begins as ridging begins to develop. High temps begin to inch
closer to being just slightly above normal, with highs for interior
regions reaching into the low to mid 90s, 60s still at the coast.
Monday, temperatures warm further with upper 90s for most interior
locations, perhaps a few very isolated pockets of low 100s. Its
still 5+ days out, but the forecast is trending towards a bit of a
warmup for next week. At this point, its still a bit too early to
say how warm things will be for the 4th of July holiday, but this
will be something we`re keeping our eyes on given the potential for
plenty of people to be outdoors attending parades and fireworks
displays. CPC 6-10 and 8-14 day outlooks indicate above-normal
temperatures for our region, consistent with a building ridge over
the region. Stay tuned, and enjoy the cooler weather this week while
it lasts!

&&

.AVIATION...
(06Z TAFS)
Issued at 1034 PM PDT Wed Jun 26 2024

Currently VFR at all terminals. Winds will remain onshore through
the TAF period. Tonight, OAK and SFO are expected to deteriorate
to low-end MVFR while the Monterey Bay terminals of MRY and SNS
are expected to deteriorate to low-end IFR. Widespread VFR to
prevail by late morning. Similar conditions are expected tomorrow
night with a slight improvement in ceiling height at the Monterey
Bay terminals of MRY and SNS.

Vicinity of SFO...Currently VFR with westerly flow. Winds will
prevail out of the west through the TAF period. A low-end MVFR
ceiling will impact the terminal overnight before improving to VFR
by the late morning. A low-end MVFR ceiling will return to the
terminal towards the end of the TAF period.

SFO Bridge Approach...Similar to SFO.

Monterey Bay Terminals...Currently VFR with southwesterly flow at
MRY and VFR with northerly flow at SNS. Winds will remain onshore
through the TAF period. Both terminals are expected to deteriorate
to low-end IFR tonight, briefly improving to VFR by the late morning
before IFR ceilings return to the terminals again tomorrow
evening.

&&

.MARINE...
(Tonight through next Tuesday)
Issued at 1034 PM PDT Wed Jun 26 2024

  Breezy to gusty northwesterly breezes with gusts approaching
gale force conditions last through the weekend and into the next
work week. Wind is the main driver for the Small Craft Advisories
as  significant wave heights generally remain below 10 feet
through  the period.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
CA...None.
PZ...Small Craft Advisory from 3 PM to 9 PM PDT Thursday for Mry Bay.

     Small Craft Advisory until 3 AM PDT Friday for Pt Arena to Pt
     Reyes 0-10 nm-Pt Pinos to Pt Piedras Blancas 0-10 nm-Pt
     Reyes to Pigeon Pt 0-10 nm.

     Small Craft Advisory until 3 AM PDT Thursday for Pigeon Pt to Pt
     Pinos 0-10 nm.

     Small Craft Advisory from 9 AM to 9 PM PDT Thursday for Pigeon
     Pt to Pt Pinos 0-10 nm.

     Small Craft Advisory until 9 AM PDT Friday for Pigeon Pt to Pt
     Pinos 10-60 NM-Pt Arena to Pt Reyes 10-60 NM.

&&

$$

SHORT TERM...AC
LONG TERM....AC
AVIATION...Sarment
MARINE...Canepa

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