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000
FXUS66 KMTR 261748
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1048 AM PDT THU MAY 26 2016

.SYNOPSIS...High pressure will lead to a warming trend today
through at least Saturday, especially inland with afternoon
readings back into the 80s and lower 90s. A marine layer will
persist near the coast. Latest long range models suggest
seasonably warm weather to continue inland areas Sunday through
Memorial Day.

&&

&&

.DISCUSSION...as of 09:16 AM PDT Thursday...Summer like pattern
over the Bay Area this morning, low clouds, patchy fog and coastal
drizzle. Bay Area profilers and sodars put the marine layer depth
near 2000-2500 ft. Additionally, there have been numerous reports
of drizzle during the morning commute. The latest forecast handles
this rather well so no short term update is needed this morning.

As mentioned previously, the burn off this morning will be earlier
than the last few days. KSFO is already reporting clear, which
did not happen the last two days. Interior locations are also
clearing out. The earlier burn off and warming airmass will lead
to warmer temperatures across the Bay Area today. Generally
speaking, highs will be in the 60s coast, 70/80s inland or about 5
to 10 degrees warmer than yesterday.

Warmer weather will continue into the upcoming holiday weekend.

&&

.PREV DISCUSSION...as of 3:48 AM PDT Thursday...Main theme for
today will be to mark the beginning of a warming trend, especially
after a fairly prolonged cool spell for the inland valleys. As
skies turn sunny this afternoon expect afternoon readings back to
more seasonable levels with more widespread 70s and even some
lower 80s.

Warming trend, especially inland will continue Friday and Saturday
as 850 mb temps warm and the marine layer gets eroded under a
developing northerly wind that should show up in the hills Friday
night into Saturday morning. Temperatures are forecast to jump
significantly on Friday with inland areas well into the 80s and
lower 90s, not at all unusual for this time of year but much
warmer than the last week or so. The combination of some northerly
winds Saturday morning should lead to continued warming to start
out the holiday weekend. It looks like pool weather will arrive
just in time while typical 60s will persist along area beaches.

There could be a brief cool down Sunday with a return of some
marine air and onshore flow. However the ECMWF and GFS are now
showing another warm solution for Memorial Day with a 584 dm high
west of San Francisco with an associated thermal trough along the
coast. So looking like a warm and dry holiday weekend with nice
travel weather for the bay area and minimal fog.

Long range ECMWF for early next week looks high and dry at least
through Weds with perhaps a trough approaching by the middle of
next week to induce some inland cooling.

&&

.AVIATION...as of 10:50 AM PDT Thursday...Clouds have burned-off
for most of the terminals at this hour. Rest of the day should
stay VFR with MVFR CIGS forecast to return after 06Z tonight.
Winds generally from 240 to 280 with typical afternoon seabreeze
gusts. High Confidence.

Vicinity of KSFO...VFR through at least 06Z before return of MVR
conditions around 07Z. Should see break-out similar time tomorrow
or even an hour earlier. Winds becoming mostly 260 to 280 with
gusts over 20 KT from 20Z to 04Z. High confidence.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR possible through most of the period
at KMRY with more clearing expected at KSNS. Winds from 240 to 280
increasing through the day with gusts at KSTS forecast to be
around 20 KT at 20Z. Early return of stratus at both spots by 03Z
 at the latest. Moderate confidence.

&&

.MARINE...as of 10:39 AM PDT Thursday...Expect gusty northwesterly
winds across the waters through friday as a ridge of high pressure
builds into the region. The northerly winds will also result in
hazardous conditions from steep fresh swell. Winds will be
strongest in the outer waters north of point reyes.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Pigeon Pt to Pt Pinos 0-10 nm from 3 PM
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pt Reyes to Pigeon Pt 0-10 nm
             SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm

&&

$$

PUBLIC FORECAST: MM
AVIATION: Bell
MARINE: Bell


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000
FXUS66 KMTR 252051
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
151 PM PDT WED MAY 25 2016

.SYNOPSIS...A building ridge of high pressure along the coast will
result in a gradual warming trend through the upcoming weekend
along with dry weather conditions.

.DISCUSSION...as of 01:50 PM PDT Wednesday...Low cloud cover over
inland areas of the region continue to erode this afternoon with
daytime heating. Meanwhile, do see some cumulus developing over
the higher terrain as expected with lingering moisture aloft. The
most development remains over the inland portion of the North Bay
Mountains where a few showers and potentially a thunderstorm or
two will be possible this afternoon. Otherwise, most locations
across the region will remain dry as the main mid/upper level
system over southern California shifts to the east today and
tonight. Low clouds will likely spread back inland this evening
and persist through Thursday morning. In addition, patchy drizzle
is once again expected along coastal areas overnight into Thursday
morning.

A building ridge of high pressure will become the dominate
weather feature across the region for the remainder of the week
and result in a gradual warming trend. By tomorrow afternoon, most
inland locations will be around 5 degrees warmer compared to this
afternoon. While the marine influence will keep coastal areas
cooler, may see a few degrees of warming with more afternoon
sunshine on both Thursday and Friday.

The ridge will strengthen and temperatures will warm aloft
through the upcoming Memorial Day Holiday Weekend. This will
result in inland temperatures warming back into the upper 70s to
mid 80s with coastal areas generally in the upper 60s to lower
70s. While overnight and morning coastal stratus will likely
continue as a result of onshore flow, dry weather conditions are
expected region- wide into early next week.

&&

.AVIATION...as of 10:31 AM PDT Tuesday...Widespread stratus with
decent onshore feed. Only minor tweak to the 12z tafs. Do expect
gradually clearing from 19-21z for most terminals. Better shot for
more VFR conditions this afternoon unlike yesterday. Cigs return
tonight with more stratus.

Vicinity of KSFO...Feeling a little more optimistic today for
better clearing...well at least going to more a SCT cig this
afternoon. For now...will show improvement from 19-20z. The fly
in the ointment to watch is the rapid clearing over the S Bay and
its northward movement.

SFO Bridge Approach...If the latest trend on satellite continues,
clearing may occur a little sooner on the approach.

Monterey Bay Terminals...MVFR cigs through 19-20z this afternoon.
Cigs return this evening with MVFR/IFR overnight. Onshore winds
10 to 15 kt with gusts up to 20 kt in the afternoon.

&&

.CLIMATE...Fun climate facts -- downtown San Francisco has picked
up nearly 23" since October 1st which is 99% of average. We are
currently just 0.12" drier than normal. This is the most rainfall
in San Francisco for the same period since 2010-2011. It is also
nearly double the amount recorded October 1st, 2013, to May 25th,
2014.

&&

.MARINE...as of 09:30 AM PDT Wednesday...Building high pressure
will result in gusty northerly winds over the coastal waters today
through the weekend. Winds will be strongest in the outer waters
north of Point Reyes. Hazardous conditions from fresh squared
seas will exist as northwest seas build to match the period today
and tomorrow.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pigeon Pt to Pt Pinos 0-10 nm
             SCA...Pt Pinos to Pt Piedras Blancas 0-10 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm
             SCA...Pt Reyes to Pigeon Pt 0-10 nm
             SCA...Mry Bay until 9 PM
             SCA...SF Bay until 9 PM

&&

$$

PUBLIC FORECAST: RGass
AVIATION: MM
MARINE: MM
CLIMATE: Bell


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000
FXUS66 KMTR 250519
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1019 PM PDT TUE MAY 24 2016

.SYNOPSIS...Showers and potentially an isolated thunderstorm or
two will be possible over the inland hills/mountains through this
evening. Otherwise, temperatures will remain seasonably cool
through Wednesday with diminishing chances of showers. A gradual
warming and drying trend is then slated for the remainder of the
week and into the upcoming weekend.

&&

.DISCUSSION...As of 8:53 PM PDT Tuesday...A few showers still
linger across the region this evening. Most notably over the Santa
Lucia Range and the hills of San Benito, Santa Clara and Alameda.
The Santa Rita RAWS located near the southern tip of San Benito
County has reported 0.08" over the last few hours with 0.02"
reported at Limekiln Creek in Monterey County. 0.12" and 0.11" has
also been reported at Chews Ridge and Ventana Cone (in Monterey
County), respectively over the last 6 hours. Models indicate
lingering showers possible through tonight mainly over the areas
mentioned above. The potential for isolated thunderstorms still
exist given the unstable airmass aloft, however as the sun sets
this evening chances will diminish.

Latest water vapor imagery as well as the last few frames of the
visible imagery depicts a nicely formed upper low centered at
approx. 200 NM southwest of the Monterey Peninsula. The upper
level trough and associated closed low responsible for the
unsettled/unstable weather we have seen for the past couple of
days is forecast to dig a bit further south before swinging across
South-Central California on Wednesday. The trough is then progged
to continue moving eastward Thursday as high pressure gradually
strengthens over the Eastern Pacific. This will result in a
gradual warming and drying trend across the district. Temperatures
will warm a few degrees on Wednesday. However they will likely
remain below average for this time of year. A few lingering
showers cannot be ruled out for Wednesday due to the proximity of
the low as it moves across the southern half of the state.

By Thursday the low will be well east of the region and high
pressure will regain control of the area. 500MB heights and
850MB temps will rise sharply translating into above average
temperatures across the region. Temperatures will continue to warm
into friday and remain warm through the weekend with temperatures
reaching into the 60s to lower 70s along the coast and 70s to
lower 80s inland. Models indicate there will be periods of
offshore flow through the weekend as a thermal trough develops
along the coast.

The ridge of high pressure building over the Eastern Pacific is
forecast to gradually shift east through the weekend and into
early next week. This will maintain warm and dry conditions
through early next week.

&&

.AVIATION...as of 10:19 PM PDT Tuesday...A closed upper level low
southwest of the Monterey Peninsula will move southeast and be
near Point Mugu Wednesday morning. Low cloud coverage will
continue to increase tonight. Patchy drizzle or sprinkles are a
possibility into Wednesday morning.

Vicinity of KSFO...MVFR cig tonight. VFR forecast to return by late
Wednesday morning. Westerly wind gusts to 20-25 knots develop by 20z
Wednesday continuing into Wednesday evening.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR cigs tonight with clearing by late
Wednesday morning.

&&

.MARINE...as of 06:54 PM PDT Tuesday...Northerly winds and seas
will gradually increase tonight and wednesday. Winds will be
strongest north of Point Reyes. The strong and gusty winds will
persist into the weekend.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pt Arena to Pigeon Pt 10-60 nm from 3 AM

&&

$$

PUBLIC FORECAST: CW
AVIATION: Canepa
MARINE: MM


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000
FXUS66 KMTR 241725
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1025 AM PDT TUE MAY 24 2016

.SYNOPSIS...A weak low pressure system will bring a slight chance
of showers and a thunderstorm or two to our region today.
Temperatures will be seasonably cool, but gradually warm later in
the week.

&&

.DISCUSSION...as of 8:45 AM PDT Tuesday...Widespread cloud cover
over the region this morning with temperatures generally in the
50s. Meanwhile, a long wave trough extends down the Pacific
Northwest into northern and central California. Increased moisture
and weak disturbances riding along the trough will result in
chances for showers and thunderstorms over a portion of the region
again this afternoon. Have updated the ongoing forecast to
included convection over the Santa Lucia Mountains for this
afternoon along with the North and East Bay Hills/Mountains and
the higher terrain of San Benito County. Otherwise, cooler than
average temperatures expected for the remainder of the day with
most locations only warming into the 60s to lower 70s.

Note: Current visibility sensor at KSNS (Salinas Airport) has been
inaccurate since Monday morning. NWS Technicians are on site
looking into the problem this morning.

&&

.PREVIOUS DISCUSSION...as of 3:30 AM PDT Tuesday...Widespread
clouds this morning across most of our CWA with a onshore west-to-
east gradient of 1.5 MB. Synoptically, a longwave trof extending
from Central Canada remains across our entire region. Similar to
yesterday a weak impulse will move through our cwa today and
likely trigger a few showers. Lifted values are forecast to drop
to below zero values over parts of the North Bay plus eastern
sections of the CWA, therefore still looks like a slight chance of
thunderstorms. The pattern also favors small hail with any of the
cells. The trof will start to progress to the east by Wednesday
afternoon which will effectively bring an end of precipitation.

Our string of cooler than normal conditions will continue through
at least Wednesday with many spots in the 60s to lower 70s. As a
ridge starts to build back starting on Thursday, temperatures will
warm back closer to normal values. That trend will continue into
weekend with the range in the mid 60s to the upper 70s. A few
lower 80s cannot be ruled out for far southern and eastern
sections.

Longer range outlook favors warmer than normal conditions next
week with mostly dry conditions.
&&

.AVIATION...as of 10:19 AM PDT Tuesday...Tricky forecast the next
hour or two as morning stratus erodes and afternoon strato cu
develops. For the most part, MVFR transitioning to VFR in the
18-19z time frame. Expecting mostly VFR this afternoon with
elevated cu, but cigs may be borderline MVFR/near 3K feet. Moist
low level will allow for MVFR cigs tonight with a few pockets of
IFR conditions.

Vicinity of KSFO...Transition period as blue skies are starting
to show up on airport cams and visible satellite. Pushed clearing
for KSFO until 18z, but it will likely be a dirty clearing with
lingering clouds. KOAK will hold onto cigs slightly longer. VFR
this afternoon, but cannot rule out a passing BKN030 from time to
time. MVFR cigs develop overnight.

SFO Bridge Approach...Similar to KSFO. However, far southern end
of approach will see even less clouds in the short term.

Monterey Bay Terminals...Lingering MVFR cigs from 18-19z. Strato
cu this afternoon. MVFR cigs return again tonight.

&&

.MARINE...as of 08:43 AM PDT Tuesday...Light to moderate winds and
small seas will persist today. Winds will increase tonight and
Wednesday as high pressure builds over the region. The winds will
be strongest north of Point Reyes.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...NONE.

&&

$$

PUBLIC FORECAST: RGass
AVIATION: MM
MARINE: MM


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000
FXUS66 KMTR 241156
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
456 AM PDT TUE MAY 24 2016

.SYNOPSIS...A weak low pressure system will bring a slight chance
of showers and a thunderstorm or two to our region today.
Temperatures will be seasonably cool, but gradually warm later in
the week.

&&

.DISCUSSION...AS OF 3:30 AM PDT Tuesday...Widespread clouds this
morning across most of our CWA with a onshore west-to-east
gradient of 1.5 MB. Synoptically, a longwave trof extending from
Central Canada remains across our entire region. Similar to
yesterday a weak impulse will move through our cwa today and
likely trigger a few showers. Lifted values are forecast to drop
to below zero values over parts of the North Bay plus eastern
sections of the CWA, therefore still looks like a slight chance of
thunderstorms. The pattern also favors small hail with any of the
cells. The trof will start to progress to the east by Wednesday
afternoon which will effectively bring an end of precipitation.

Our string of cooler than normal conditions will continue through
at least Wednesday with many spots in the 60s to lower 70s. As a
ridge starts to build back starting on Thursday, temperatures will
warm back closer to normal values. That trend will continue into
weekend with the range in the mid 60s to the upper 70s. A few
lower 80s cannot be ruled out for far southern and eastern
sections.

Longer range outlook favors warmer than normal conditions next
week with mostly dry conditions.
&&

.AVIATION...As of 04:55 AM PDT Tuesday... Marine stratus
infiltrating coastal and inland valleys this morning as upper
trough looms aloft. Marine stratus will linger until 17-18Z
timeframe for most locations. Drizzle along coast possible this
morning. A few light showers are also possible throughout the day
with wrap around energy and moisture. Onshore winds generally 16
kt or less, increasing Wednesday afternoon. MVFR cigs return
overnight.

Vicinity of KSFO...MVFR through 17-18z timeframe, then vfr.
Onshore winds up to 15 kt this afternoon. MVFR returns after 04z
tonight.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR cigs with drizzle through 18z, then
VFR with partly to mostly cloudy skies lingering through the
afternoon. Onshore winds generally 12 kt or less, with occasional
gusts through the afternoon. Light rain showers possible through
the day. MVFR cigs return this evening.

&&

.MARINE...as of 3:30 AM PDT Tuesday...Low pressure will persist
over the region through midweek and result in moderate northwest
winds...especially over the northern outer waters. High pressure
builds over the coastal waters later in the week to bring
increasing northwesterly winds and building fresh seas.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...NONE.

&&

$$

PUBLIC FORECAST: Bell
AVIATION: DRP
MARINE: DRP


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