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000
FXUS65 KPSR 301111
AFDPSR

Area Forecast Discussion
National Weather Service Phoenix AZ
411 AM MST MON MAY 30 2016

.UPDATE...Updated aviation discussion.

&&

.SYNOPSIS...
A slow-moving low pressure system across the desert southwest will
persist through Tuesday yielding cooler than normal temperatures and
mostly dry conditions. Thereafter high pressure builds over the
regions for a sharp warming trend. By the weekend, many lower desert
locations will reach the 110 degree mark.

&&

.DISCUSSION...
Today through Wednesday...
A weak upper low is centered over the Mohave Desert early this
morning. To the north is an upper trough centered with an axis over
the northern Rockies. In between the low and the trough is a
deformation zone. Upstream of our low is a ridge just offshore.
Satellite imagery shows indications of outflows and gravity waves
pushing westward to the Continental Divide due to convection over the
Plains (especially northern Texas). As the low slowly drifts east-
southeastward, it will try to tap into moisture from the Plains as
well as subtropical moisture from Baja and Sonora. Being that it is
weak, the moist advection will be meager. However, both hi-res and
larger scale models depict convection developing over northern AZ
today with more coverage Tuesday. With the low center dipping south
of the Mexico border by Tuesday afternoon, northeasterly steering
flow will help move storms from the Rim and Yavapai County into
south-central AZ. This would primarily affect southern Gila and
northern Maricopa Counties. The nature of the convection will be
high based and shallow given the very modest moisture availability.
Thus, no real precip opportunity but rather there will be gusty wind
potential and thus blowing dust potential. Our local WRF-NMM is the
most aggressive with the coverage and even has La Paz County and
Pima County getting into the mix. Other models (including NCEP WRFs
and UofA WRFs) are not as optimistic. Held on to the patchy blowing
dust in the grids for late Tuesday afternoon and evening but pared
back the area. By Wednesday afternoon, the low will be centered over
the Sonora/Chihuahua border. With lingering moisture and
northeasterly steering flow, added mention of slight chance t-storms
for our higher terrain zone northeast and east of metro Phoenix for
Wed. aft/eve.

As for temperatures, they will be a little bit below normal today and
near normal Tuesday (slightly above near and west of the Lower
Colorado River Valley). There will be additional warming Wednesday as
the low exits and the ridge advances inland. That will be the first
day of this week for 100 degree mark over the Phoenix area.

Thursday through Sunday...
The short story is that a strong ridge keeps building inland with
500mb heights in the 592-594dm range Friday and Saturday. NAEFS
depicts 850mb temps reaching and exceeding the 90th percentile both
of those days (especially Saturday). This pattern will result in well
above normal temperatures (even for early June) with most lower
deserts reaching the 110 degree mark Friday and Saturday. One minor caveat
is a backdoor front pushing against the Continental Divide late in
the week which could conceivably keep temps over south-central AZ
slightly below forecast but probably would only be felt over the
higher terrain - if at all. The ridge starts shifting eastward Sunday
in response to an advancing low pressure system leading to slight
cooling (more noticeably for southeast CA).

&&

.AVIATION...
South-Central Arizona Including KPHX, KIWA, and KSDL...

A weak low pressure system will move into Arizona today, though no
direct aviation weather impacts are anticipated through Tuesday
morning. Winds will generally remain less than 10 kt and follow
typical upslope/downslope patterns across the Phoenix area.

Southeast California/Southwest Arizona Including KIPL and KBLH...

Lighter than normal winds are expected through Tuesday. At KIPL,
directions will vary while at KBLH, winds will generally retain a
southerly or easterly component.

Aviation discussion not updated for amended TAFs.

&&

.FIRE WEATHER...
Wednesday through Sunday...
A strong high pressure system is forecast to build into the region
providing some of the warmest afternoon temperatures of the year by
the weekend. Afternoon temperatures will be 5 to 8 degrees above
normal. Typical afternoon and evening southwest winds 10 to 15 mph
are expected each day. Good recovery is expected at night. Minimum
relative humidities are generally expected in the 8 to 12 percent
range.

&&

.SPOTTER INFORMATION STATEMENT...
Spotter activation is not expected.

&&

.PSR WATCHES/WARNINGS/ADVISORIES...
AZ...None.
CA...None.
&&

$$

Visit us on Facebook...Twitter...and at weather.gov/phoenix

DISCUSSION...AJ
AVIATION...Hirsch
FIRE WEATHER...Vasquez



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000
FXUS66 KSTO 301030
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
330 AM PDT MON MAY 30 2016

.SYNOPSIS...
Very warm weather expected this week as high pressure strengthens.

&&

.DISCUSSION...
Clear skies across interior NorCal early this morning except for
some high clouds spilling over the ridge along 130W. The mountain
valleys are cool - mainly in the 30s and 40s under clear skies
while the valley and foothills are generally on the mild side with
current temps in the mid 60s to lower 70s, except in the mid 50s
to around 60 through the Delta and into the Sacramento and
Stockton region.

The main weather story for the region this week will be hot
weather as the ridge over the eastern Pacific shifts over NorCal
to kick off meteorological summer. Warmest temperatures will be
around the century mark in the Central Valley as 850 mb temps
climb into the lower to mid 20s C and subsidence increases. A
Delta trickle should persist through the week shaving a few
degrees off temps around Fairfield.

Little if any late day shower and thunderstorm activity is
expected over the northern Sierra.

&&

.EXTENDED DISCUSSION (FRIDAY THROUGH MONDAY)...
Strong high pressure will rule the area through the end of the
work week into the start of the weekend with well above normal
temperatures. Models continue to advertise a closed upper low
approaching the CA coast by late Saturday into Sunday. Differences
remain with track of low and how far south into CA it will move
before being ingested into larger scale trough. GFS paints more
widespread precip, mainly across higher elevations. ECMWF with
further south solution/less widespread precipitation. For now,
have included chance of showers and thunderstorms across higher
elevations for the end of the weekend, until discrepancies are
better resolved. Regardless, should lend itself to some relief
from the heat with temperatures on Sunday around 5 to 10 degrees
cooler than Saturday and increasing flow through the Delta. CEO

&&

.AVIATION...
VFR conditions for TAF sites with light winds. A few
thunderstorms near the Sierra crest, south of Lake Tahoe this
afternoon/evening.

&&

.STO Watches/Warnings/Advisories...None.

&&

$$



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000
FXUS65 KREV 300957
AFDREV

Area Forecast Discussion
National Weather Service Reno NV
257 AM PDT MON MAY 30 2016

.SYNOPSIS...
Isolated thunderstorms will be confined to the Sierra crest south
of Lake Tahoe today. Otherwise, a significant warming trend is on
track this week with high temperatures reaching 80 degrees in the
Sierra and into the 90s across the lower valleys.

&&

.SHORT TERM...

Very few changes were made as confidence remains high in a strong
ridge building into the region by midweek. This will not only
suppress thunderstorms but it will also lead to unseasonably hot
daytime temperatures with both MOS guidance and local temperature
study showing highs pushing well into the 90s for lower valleys by
Wednesday. We have maintained a slight chance of thunderstorms
along the Sierra crest this afternoon. However, any storms that
develop will have a tendency to drift west of the crest due to
northeast flow in the storm bearing layer. Models are showing some
convection Tue-Wed underneath ridge although 500mb temps warmer
than -10C will limit potential with some cumulus buildups more
likely. Hohmann

.LONG TERM...Thursday through Sunday...

Ridge continues to strengthen through the last part of the week
and into the weekend. An area of low pressure will move into the
Central CA coast on Saturday, helping to pump up the ridge and
temperatures aloft even more for Saturday. Forecaster confidence
is high regarding a significant warming trend and well above
normal temperatures in the extended. High temperatures will climb
into the mid 90s across western NV and northeast CA, with upper
70s and low 80s in the Sierra Valleys.

Models have trended drier air into the region on Thursday and
Friday, lowering the chance of showers and thunderstorms, along
with a stronger capping inversion at 500mb. We removed the mention
of convection for Friday based off this. By the weekend however,
we should start to see increasing chances for convection as the
low pressure moving into the CA coast with increased moisture and
instability with cooler temperatures aloft. These storms may also
end up being stronger that what we`ve seen lately due to more
shear and instability. Hoon

&&

.AVIATION...

VFR conditions remain through today with light winds and dry
conditions for most terminals. A few isolated showers are possible
at KMMH this afternoon. Overall chances for showers or storms at
KMMH generally less than 15%. Diminishing chances for
thunderstorms after today with a strong warming trend through the
rest of the week. Hoon

&&

.REV Watches/Warnings/Advisories...
NV...None.
CA...None.
&&

$$

For more information from the National Weather Service visit...
http://weather.gov/reno



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000
FXUS66 KLOX 300558
AFDLOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1058 PM PDT SUN MAY 29 2016

.SYNOPSIS...
The cut-off low pressure system over Southern California will
support the slight chance of thunderstorms this afternoon and
early evening across the mountains and Antelope Valley. High
pressure aloft will build into the area by the middle of next
week, supporting much warmer conditions that may persist into next
weekend.

&&

.SHORT TERM...(TDY-TUE)

Nearly all shower and thunderstorm activity has dissipated
this evening. Low clouds lingered through the day across
coastal sections of southern Sba County, and have already
surged into the Central Coast and into coastal sections of
Vtu county this evening. Expect clouds to overspread coastal
areas and push into the valleys before midnight. The marine
layer was deep enough to allow clouds to push into coastal
slopes overnight.

The upper low just east of the region will continue to move
eastward overnight and Monday. Heights will begin to rise across
the forecast area on Monday, and the marine layer should being
to become more shallow. Gradients will be less strongly onshore
on Monday as well. This should allow for better and faster
clearing in all areas on Monday, although clouds could still
linger into the afternoon at some beaches. There should be
a few degrees of warming on Monday, especially in the valleys,
mountains and deserts.

***From previous discussion***

Tuesday through Wednesday, the upper level ridge of high pressure
will continue to slowly slide eastward and become more centered
across California, resulting in a continued warming trend, along
with a shrinking marine layer.

.LONG TERM...(WED-SAT)

Thursday looks to be the warmest day of the week for many areas as
thickness values peak. Warmest valleys expected to climb to around
90 degrees, with Antelope Valley climbing to around 100 degrees.
A shallow marine layer will continue to keep coastal low clouds
and fog. Friday through Sunday, 12z GFS and ECMWF models showing
another cutoff low developing off the Southern California coast,
with cross sections showing a good surge of mid and upper level
clouds. With this type of pattern, not out of the question that
we could see some showers or mountain tstms develop across the
forecast area sometime during this period, but probability at this
time is still around 10 percent.

&&

.AVIATION...31/06Z...

At 05Z at KLAX... the inversion was about 1300 feet deep. The top
was near 4850 feet with a temperature of eighteen degrees Celsius.

OVERALL... Moderate to high confidence in the 06Z TAFS. The
slightly reduced confidence is due to the general uncertainty in
marine incursion behavior and because the category changes and
ceiling/clearing times may be off by +/- 2 hours. Some locales may
not fully clear prior to the marine incursion returning tomorrow
evening. Otherwise and elsewhere VFR conditions are expected.

KLAX... Moderate to high confidence in the 06Z TAF. The slightly
reduced confidence is due to the general uncertainty in marine
incursion behavior and because the category changes and
ceiling/clearing times may be off by +/- 2 hours. There is a
fifteen percent chance that MVFR conditions will not clear
tomorrow.

KBUR... moderate to high confidence in the 06Z TAF. The slightly
reduced confidence is due to the general uncertainty in marine
incursion behavior and because the category changes and
ceiling/clearing times may be off by +/- 2 hours. There is a ten
percent chance that MVFR conditions will not clear tomorrow.

&&

.MARINE...29/830 PM...

Small craft advisory conditions are not expected through
Friday. Otherwise a Catalina eddy is expected to develop each
night over the bight through Thursday and northwest winds are
expected elsewhere and will fill in the bight each afternoon.

A complex of storm systems south of the equator will create a
southerly swell of around 5 ft and a longer period swell across
the local waters by next Wednesday. The swells will remain below
small craft advisory for hazardous sea conditions but there will
be extra surging and currents along exposed south facing shores.
In the meantime a mixed small south swell and locally generated
northwest swell continue.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&
$$

PUBLIC...Gomberg/DB
AVIATION...KJ
MARINE...CK
SYNOPSIS...Munroe

weather.gov/losangeles



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000
FXUS66 KMTR 300526
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1026 PM PDT SUN MAY 29 2016

.SYNOPSIS...A deep marine layer and light onshore flow will
maintain low clouds along the coast tonight...portions of the
inland valleys will also see low clouds overnight. A warming
trend will begin Memorial Day with warm temperatures expected through
the end of the week...the coast is anticipated to remain cool.

&&

.Discussion...As of 9:17 PM PDT Sunday...Low clouds are in place
along the coast with the Fort Ord profiler showing the depth of
the marine layer reaching 2000 feet. Halfmoon Bay Airport is
currently reporting cigs at 300 feet and Monterey Airport is
reporting cigs at 800 feet...suggesting a thick cloud layer.
Gentle onshore flow should push these clouds into the inland
valleys overnight.

The current satellite water vapour image is showing high pressure
building over the Eastern Pacific while a low pressure system
pushes into the desert south west. The 1200Z ECMWF and 0000Z GFS20
have initialized well with the current synoptic pattern and remain
in good agreement through at least next weekend. Over the next few
days both models build a ridge of high pressure over the Eastern
Pacific and California. This will result in a warming
trend...primarily for the inland areas and will also maintain dry
weather through at least Friday.

Both models are in pretty good agreement with an upper level low
approaching southern california towards the end of the work week.
If this low actually materializes it will begin to impact southern
and central California on Saturday. The 1800Z GFS20 is showing
some upper level moisture and elevated instability over the Big
Sur Coast on Saturday and Sunday. These ingredients could result
in elevated thunderstorms so we will need to keep a good eye on
this developing weather scenario. This is my first forecast shift
in a few days so I`m reluctant to add thunder to next weekends
forecast. However...if the models continue to show this scenariowe
may need to add them in.

&&

.AVIATION...as of 10:30 PM PDT Sunday...Coastal clouds are
starting to spread into SFO Bay so there is a better chance for
cigs in the SFO Bay Area tonight. Marine layer is around 2000 feet
so burnoff should be around 18z.

Vicinity of KSFO...MVFR after 08z.

SFO Bridge Approach...Same as KSFO.

Monterey Bay Terminals...IFR through 17-18z.

&&

.MARINE...as of 10:30 PM PDT Sunday...HIGH PRESSURE COVERS THE
EASTERN PACIFIC WITH A RIDGE EXTENDING INTO THE PACIFIC NORTHWEST.
THIS IS BRINGING GUSTY NORTHWEST WINDS OVER THE OUTER WATERS. THE
RIDGE WILL WEAKEN ON MONDAY ALLOWING FOR WINDS TO DECREASE. A
BUILDING SOUTHERLY SWELL IS ANTICIPATED TO ARRIVE EARLY NEXT WEEK.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm until 11 PM
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm until 2 AM

&&

$$

PUBLIC FORECAST: Larry
AVIATION: W Pi
MARINE: W Pi


Visit us at www.weather.gov/sanfrancisco

Follow us on Facebook and twitter at:
www.Facebook.com/nwsbayarea
www.twitter.com/nwsbayarea



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000
FXUS66 KEKA 292215
AFDEKA

Area Forecast Discussion
National Weather Service Eureka CA
315 PM PDT SUN MAY 29 2016

.SYNOPSIS...
High pressure will bring dry weather and warming temperatures to
northern California through the upcoming week. The weather pattern
could become more interesting by next weekend.

&&

.DISCUSSION...
.SHORT TERM...
(Tonight and Monday)

More tranquil conditions will return to the area overnight and
tomorrow, as winds continue their downward trend compared to recent
days. The one thing that has been rather stubborn is marine stratus
along the coast in Humboldt County. Similar to yesterday, it finally
mixed out of the Eel River Valley, although here it took its sweet
time today. Looking farther offshore and to our north, clear skies
can be seen on the visible satellite imagery this afternoon,
leading one to believe it shouldn`t be much of an issue tonight.
However, northerly winds will persist so we have some concern this
may redevelop again overnight, but perhaps in more of a scattered
nature. This is something we`ll keep an eye on as the night
progresses.

Otherwise, lighter winds and rising 500mb heights will lead to
warmer temperatures for Monday, as afternoon highs climb about
5 degrees compared to today, with mostly sunny skies expected.

.LONG TERM...
(Monday evening through next Sunday)

Continued warmth and clear skies will be the main theme much of the
week, before things get more muddled for the weekend. An area of
high pressure aloft will traverse the forecast area Monday
night/Tuesday. Clear skies and seasonably warm temperatures will
continue through much of the week.

The ridge axis will pass to our east by Wednesday, with subsidence
becoming less of an issue during the day. The models continue to
show decent instability during the afternoon/evening hours for
locations east of highway 101, with the best overlap of instability
and negligible to no CINH located across the Trinity Alps. Although
no real disturbance is seen in the vorticity pattern to help aid in
convective development, the combination of surface heating,
orographics, and decent instability (SBCAPEs >1500 J/kg) may be
enough for one or two storms to develop. Otherwise, dry conditions
will prevail area-wide.

Heading into the weekend forecast challenges increase, especially
for Sunday. The models continue to "wobble" with regard to the track
of a mid-level area of low pressure tracking towards/across the
state. The GFS has trended farther north, similar to the more
consistent ECMWF regarding the positioning of this feature. However,
it too has shifted the track some towards its GFS counterpart,
shifting its forecast slightly south towards the GFS position. The
Canadian model is in the middle of these two and seems like a good
compromise at this point. In any event, these changes will
continue over the next few days until the system gets closer,
where the leading edge of it can get sampled by our RAOB network.

The end game in all this is things continue to look
interesting/promising for potential convection for the end of next
weekend. Both models continue to show moderate to strong
instability, extremely steep mid-level lapse rates, and
disturbances rotating around the low bringing periods of
increased lift aloft with them. If these trends continue over the
next few model runs, we may need to add thunder to the forecast
for the of the forecast period. /PD

&&

.AVIATION...A weak passing shortwave disrupted the offshore flow
this morning. This allowed an area of low clouds to form in around
Humboldt Bay and in the Eel River Delta. These hung around until
early afternoon. These may clear out completely before sunset.
Stronger offshore is expected tonight, however it still doesn`t look
strong enough to keep the clouds and IFR conditions completely out
of ACV, the Humboldt Bay region and the Eel river valley. For now
have them returning at ACV by 0400Z. Expect they may be a bit slower
than this to return, but until it completely disappears will hold
off on changing the forecast. MKK

&&

.MARINE...Strong high pressure over the northeastern Pacific and a
thermal low over the central valley of California is bringing gusty
northerly winds and steep, short period waves to the waters this
afternoon. Tonight the winds are expected to start to diminish. Late
tonight the small craft advisories (SCA) will expire in the inner
waters. This looks on track as the winds turn a bit more offshore
and become light at the coast. Monday afternoon winds will increase
again, but they are expected to remain slightly below small craft
advisory levels. This will need to be watched as it gets closer.

Tuesday winds look to become more southerly in the southern waters
as a southerly surge of stratus moves north. It is possible we could
see gusts to 20 kt with this surge, but will wait until it gets
closer to add it to the forecast.

Northerly winds will return Thursday into the weekend and will be in
the fresh to strong category, but current forecasts show them
remaining below gale force.

Meanwhile, model guidance continues to hint at a long period south
swells moving through the waters Wednesday. This will bring
increased wave activity to south facing beaches and anchorages with
only minor impacts expected. MKK

&&

.EKA WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
NORTHWEST CALIFORNIA COASTAL WATERS...
     Small Craft Advisory until 3 AM PDT Monday FOR PZZ450.

     Small Craft Advisory until 3 AM PDT Tuesday FOR PZZ470.

     Small Craft Advisory until 3 AM PDT Monday FOR PZZ455.

     Small Craft Advisory until 3 PM PDT Monday FOR PZZ475.

&&

$$

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Follow us on facebook and twitter at:
http://www.facebook.com/NWSEureka
http://www.twitter.com/nwseureka

FOR FORECAST ZONE INFORMATION
SEE FORECAST ZONE MAP ONLINE:
http://www.weather.gov/eureka/zonemap.png



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000
FXUS66 KHNX 292139
AFDHNX

Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
239 PM PDT SUN MAY 29 2016

.SYNOPSIS...
Dry weather and above average temperatures will prevail over the
forecast area as a strong ridge of high pressure prevails. Showers
and thunderstorms will be possible over the Sierra Nevada during the
afternoon and early evening hours.

&&

.DISCUSSION...
Showers and thunderstorms are developing over the Sierra Nevada
this afternoon in response to a weak area of low pressure moving
across southern California. There is enough instability over the
mountains and desert areas of Kern County for a few showers or an
isolated thunderstorm to develop there as well this afternoon and
early evening. Winds aloft are weak, so showers and thunderstorms
will be slow moving and will bring the possibility of locally
heavy rain. Steering winds are generally from the east, so debris
clouds from dissipating mountain showers or thunderstorms could
move over the foothills and the eastern and southern part of the
San Joaquin Valley this evening.

The low will move into Arizona tonight as a ridge of high
pressure over the eastern Pacific begins to build inland Monday
and Tuesday. Models keep sufficient instability over the Sierra
Nevada for a slight chance of showers and thunderstorms Monday and
Tuesday, but they will become more isolated each day. By
Wednesday, the threat of thunderstorms will be minimal but there
will still be some afternoon cumulus buildups.

The building ridge of high pressure will bringing warming
temperatures across the region this week. In the San Joaquin
Valley, temperatures will be near 100 degrees Tuesday, with highs
remaining near or a few degrees above 100 across much of the
valley through the week. The mountains will be warming up also
with high temperatures at 5000 feet in the 80s.

By Friday, both operational models and the ensembles develop a
closed upper low off the southern California coast. This low will
move toward southern California Saturday as the ridge shifts
eastward. As the low approaches it will create a diffluent flow
aloft over central California next weekend. It will also bring an
increase in mid and high level moisture. Thus there will be the
possibility of isolated thunderstorms at least over the mountains
next weekend. Despite this low, temperatures will still average
well above normal next weekend, but there might be a little added
humidity and sky cover. We`ll just have to wait and see how the
models handle the offshore low.

&&

.AVIATION...
Areas of MVFR and local IFR in showers and isolated thunderstorms
will continue over the mountains and southern Kern County desert
through 04z Monday and develop again near the Sierra crest after 19z
Monday. Otherwise, VFR conditions will prevail over the central
California interior during the next 24 hours.

&&

.AIR QUALITY ISSUES...
ON MONDAY MAY 30 2016... Unhealthy for sensitive groups in Fresno,
Kern and Tulare Counties. Further information is available at
Valleyair.org

&&

.CERTAINTY...

The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.php for additional information
an/or to provide feedback.

&&

.HNX Watches/Warnings/Advisories...
NONE.
&&

$$

public...Bean
avn/fw...JEB
synopsis...WP

weather.gov/hanford




000
FXUS66 KMTR 291727
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1027 AM PDT SUN MAY 29 2016

.SYNOPSIS...Slightly cooler weather is forecast for today,
especially near the coast where there will be areas of low clouds
and fog. A warming trend is then expected for Memorial Day and
Tuesday. Warmer than normal temperatures will continue through the
end of the week. Dry weather will persist.

&&

.DISCUSSION...As of 8:40 AM PDT Sunday...The first visible
satellite images this morning reveal mainly clear skies across
the North Bay region with patchy low clouds around the bay. Along
the coast stratus extends from the southern tip of Marin southward
along the coast. Across the southern half of the forecast area low
clouds have infiltrated well inland through coastal valleys under
a deepening 2000 foot marine layer. The last few visible frames
show stratus is beginning to erode over the southern salinas
valley with further clearing expected in the next hour or two.
Mainly sunny skies anticipated across the district by midday today
with the exception of coastal areas south of San Francisco that
will only see partial clearing.

Gradients at this hour continue to show a strong northerly
gradient of 4.9 mb from ACV to SFO and an equally strong onshore
gradient from SFO to LAS. A deepening marine layer and a
relatively strong onshore gradient will result in cooler
temperatures along the coast and locally inland. Temperatures
along the coast will experience a drop of up to 10 degrees.
Inland highs will only see a few degrees of cooling while the
North Bay region sees very little, if any.

Warmer conditions are expected on Memorial Day and Tuesday as an
upper level ridge of high pressure builds in over the region and
a surface trough currently situated over the interior shift west
along the coast. This will weaken the onshore gradient and thin
out the marine layer resulting in a quicker clearing of low clouds
in the morning and less marine influence. Patchy low clouds along
the coast may still be possible.

From previous discussion...The upper ridge axis is forecast to
move to our east by midweek as an upper trough develops off the
west coast along 135W. This should result in slight cooling on
Wednesday and Thursday. However, temperatures are expected to
remain above normal through the week. And, the models indicate
that temperatures will climb higher once again on Friday as the
upper ridge to our east strengthens. The ECMWF MOS indicates the
most pronounced warming late in the week, with SFO forecast to
reach 82 on Friday and Livermore 102.

The models agree that a weak upper low will develop off the
southern California coast late in the week and then lift gradually
to the northeast next weekend. The GFS forecasts precip across the
southeast portion of our forecast area by Saturday morning as the
low approaches. The ECMWF maintains dry conditions in all areas
until the following Monday night. Given these model differences
and the fact that this precipitation potential is still out at
day seven and beyond, will hold off on adding any explicit mention
of shower chances to the forecast just yet.

&&

.AVIATION...as of 10:27 AM PDT Sunday...Low clouds persist over
the Monterey Bay area with KMRY and KSNS TAFs expected to keep
MVFR cigs for the next hour or so. VFR is expected in the San
Francisco Bay area through today with low clouds spreading inland
again overnight tonight.

Vicinity of KSFO...VFR today. MVFR Cigs returning tonight after
midnight.

SFO Bridge Approach...Same as KSFO.

Monterey Bay Terminals...MVFR cigs through 18-19z...VFR this
afternoon. IFR/MVFR cigs return early tonight.

&&

.MARINE...as of 8:20 AM PDT Sunday...High pressure over the
Eastern Pacific and low pressure inland will result in gusty
northerly winds today and tonight. Winds will be strongest over
the outer waters, especially north of Point Reyes. winds will
gradually decrease on Memorial Day with weakening high pressure.
a building southerly swell is anticipated to arrive early next
week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...SF Bay
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm

&&

$$

PUBLIC FORECAST: CW
AVIATION: Sims
MARINE: Sims


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000
FXUS66 KMTR 291541
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
841 AM PDT SUN MAY 29 2016

.SYNOPSIS...Slightly cooler weather is forecast for today,
especially near the coast where there will be areas of low clouds
and fog. A warming trend is then expected for Memorial Day and
Tuesday. Warmer than normal temperatures will continue through the
end of the week. Dry weather will persist.

&&

.DISCUSSION...As of 8:40 AM PDT Sunday...The first visible
satellite images this morning reveal mainly clear skies across
the North Bay region with patchy low clouds around the bay. Along
the coast stratus extends from the southern tip of Marin southward
along the coast. Across the southern half of the forecast area low
clouds have infiltrated well inland through coastal valleys under
a deepening 2000 foot marine layer. The last few visible frames
show stratus is beginning to erode over the southern salinas
valley with further clearing expected in the next hour or two.
Mainly sunny skies anticipated across the district by midday today
with the exception of coastal areas south of San Francisco that
will only see partial clearing.

Gradients at this hour continue to show a strong northerly
gradient of 4.9 mb from ACV to SFO and an equally strong onshore
gradient from SFO to LAS. A deepening marine layer and a
relatively strong onshore gradient will result in cooler
temperatures along the coast and locally inland. Temperatures
along the coast will experience a drop of up to 10 degrees.
Inland highs will only see a few degrees of cooling while the
North Bay region sees very little, if any.

Warmer conditions are expected on Memorial Day and Tuesday as an
upper level ridge of high pressure builds in over the region and
a surface trough currently situated over the interior shift west
along the coast. This will weaken the onshore gradient and thin
out the marine layer resulting in a quicker clearing of low clouds
in the morning and less marine influence. Patchy low clouds along
the coast may still be possible.

From previous discussion...The upper ridge axis is forecast to
move to our east by midweek as an upper trough develops off the
west coast along 135W. This should result in slight cooling on
Wednesday and Thursday. However, temperatures are expected to
remain above normal through the week. And, the models indicate
that temperatures will climb higher once again on Friday as the
upper ridge to our east strengthens. The ECMWF MOS indicates the
most pronounced warming late in the week, with SFO forecast to
reach 82 on Friday and Livermore 102.

The models agree that a weak upper low will develop off the
southern California coast late in the week and then lift gradually
to the northeast next weekend. The GFS forecasts precip across the
southeast portion of our forecast area by Saturday morning as the
low approaches. The ECMWF maintains dry conditions in all areas
until the following Monday night. Given these model differences
and the fact that this precipitation potential is still out at
day seven and beyond, will hold off on adding any explicit mention
of shower chances to the forecast just yet.

&&

.AVIATION...as of 4:15 AM PDT Sunday...The northerly gradient is
weakening and loosing the battle with the southerly clouds. Latest
satellite imagery shows a low stratus decks charging up the coast.
With the exception of MRY Bay the question is how much of the
stratus deck makes it inland? Latest short range models suggest a
possible intrusion later this morning, but conf is low. Will allow
for some intrusion, but keep it short lived. VFR this afternoon,
but cigs return tonight.

Vicinity of KSFO...Conf is low for any cigs in SF Bay. However,
will forecast a few hours of MVFR cigs and KOAK and a tempo cigs
at KSFO. VFR after 17-18z. Cigs return tonight. after 12Z
possibly later. Confidence is not high as stratus could stay out
all night.

SFO Bridge Approach...less likely for any cigs in the short term.

Monterey Bay Terminals...MVFR/IFR through 18-19z...vfr this
afternoon. cigs return early tonight.

&&

.MARINE...as of 8:20 AM PDT Sunday...High pressure over the
Eastern Pacific and low pressure inland will result in gusty
northerly winds today and tonight. Winds will be strongest over
the outer waters, especially north of Point Reyes. winds will
gradually decrease on Memorial Day with weakening high pressure.
a building southerly swell is anticipated to arrive early next
week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...SF Bay from 12 PM
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm

&&

$$

PUBLIC FORECAST: CW
AVIATION: MM
MARINE: SIMS


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000
FXUS66 KSTO 291530
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
830 AM PDT SUN MAY 29 2016

.SYNOPSIS...
Very warm weather expected this week as high pressure strengthens.
A few afternoon showers or thunderstorms possible along the Sierra
crest today.

&&

.DISCUSSION...
Mainly clear skies across interior NorCal this morning.
Temperatures will inch up a few more degrees today as high
pressure strengthens a bit. Still enough moisture and instability
for another round of afternoon and early evening showers and
thunderstorms over the Sierra to the south of Tahoe. No updates.

&&

.PREVIOUS DISCUSSION...
Another warm day in store for interior NorCal today as high
pressure ridging over the Eastern Pacific begins building into the
West Coast. Highs today: valley in the low 90s, delta in the mid
70s to mid 80s, foothills in the 80s, mountain highs in the 60s
and 70s. There`s another chance for Sierra convection this
afternoon due to low pressure lingering over SoCal. However, any
showers or thunderstorms that develop will likely be limited to
the higher elevations of the Sierra south of Tahoe.

Memorial Day and Tuesday will kick off the week with hot
afternoons. High pressure will strengthen over NorCal on Monday
and Tuesday causing the peak of this current warming trend.
Valley highs will be in the mid to upper 90s. A few locations may
even top out around 100 degrees on Tuesday when daytime highs
measure 10 to 15 degrees above normal.

By Wednesday, the high pressure will begin to shift eastward and
weaken. This will finally allow temperatures to gradually cool,
but only by a few degrees. Residents should still be prepared for
a hot day with valley highs in the mid to upper 90s with 70s and
80s across higher terrain. Keep in mind to stay well hydrated for
the first half of this week as many of us are not used to the hot
afternoons.  JBB

&&

.EXTENDED DISCUSSION (THURSDAY THRU SUNDAY)...
Models continue to show strong high pressure over the western
U.S. bringing above normal temperatures through the extended
period. Daytime highs will climb slowly to more than 15 degrees
above normal by Saturday. Models fairly consistent in positioning
an upper low off the Socal coast Thursday and Friday. This will
result in southeast flow aloft and GFS, ECMWF and GEM models all
painting some convective precipitation over the northern Sierra
each afternoon. Therefore...have included a slight threat of
afternoon and evening thunderstorms in this region Thursday
through Saturday. Models diverge by next Sunday in both dealing
with the Closed low off the Socal coast and a Pacific frontal
system possibly approaching the Pacific Northwest coast. Depending
on the upper lows position...northern Sierra could see another day
of showers next Sunday. The second feature of approaching frontal
system now not looking as likely with 06z run of GFS already
backing off on this idea. Either way, should see a little cooling
most areas early next week.

&&

.AVIATION...
VFR conditions next 24 hours TAF sites. Isolated thunderstorms
possible afternoon and evening hours over the northern Sierra
crest. Sustained winds generally below 15 knots.

&&

.STO Watches/Warnings/Advisories...None.

&&

$$




000
FXUS66 KLOX 291150
AFDLOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
450 AM PDT SUN MAY 29 2016

.SYNOPSIS...
The cut-off low pressure system currently overhead will once
again support the chance for afternoon thunderstorms today in
the mountains and Antelope Valley. High pressure aloft will build
into the area by the middle of next week... supporting much warmer
conditions that will likely persist into next weekend.

&&

.SHORT TERM...(TDY-TUE)

The marine layer is 2500 feet deep and capped by a fairly strong
inversion. Marine layer stratus covers almost all of the coasts
and vlys. Good offshore trends are forecast today as an upper low
moves directly over the area. The offshore trends will allow for
slightly better and slightly faster clearing today compared to
yesterday. There is some uncertainty with this line of thinking
as there are currently onshore trends. If the pressure gradient
fcst is wrong then there will be slow to no clearing across the
coasts again.

The other big issue of the day is the thunderstorm chances. The
upper low and its associated destabilizing cool pool of air aloft
will be overhead this afternoon right at peak heating. This will
make today more unstable than yesterday...but there will be less
PVA today then ydy when the low was just to the west. Without the
PVA there may not be trigger to start the initial lift that will
allow the atmosphere to exploit the instability. Still there is
likely enough differential mtn slope heating in the mtns to kick
off some development. If TSTMs do get started then their outflows
will trigger more TSTMs in sort of an atmospheric chain reaction.
Any TSTMs that do form will be slow moving so the greatest threat
today will be flash flooding but there is not that much water to
work with and the TSTMs should be pretty short lived so the flash
flood threat is on the lower side of things.

The deep marine layer and the falling hgts caused by the upper low
will combine to produce cooler temps than normal...again.

There is a non zero chance that the outflows from the afternoon`s
and evening`s convection will mix the marine layer up a bit...but
its more likely that that will not happen and that there will be
a solid marine layer again tonight.

There should be good onshore trends on Monday and this will result
in another cloudy and cool day across most of the coasts with much
slower than normal clearing in the vlys. The upper low will be too
far away to create any shower threat but partly cloudy skies will
likely develop over the mtns in the afternoon due to sunshine and
some residual low level moisture.

A ridge builds in on Tuesday and hgts climb up to 582 DM. This
kind of warming aloft will really strengthen and squash the
inversion. The lower marine layer depth will not allow as many
clouds into the vlys as previous mornings but the very strong
inversion will be hard to bust up and again many beaches may stay
cloudy. Max temps will leap to above normal readings while coastal
and esp beach temperatures will hardly change at all.

.LONG TERM...(WED-SAT)

The ridge will persist over the area Wed and Thu. Both days will
resemble Tuesday with a shallow marine layer capped by a strong
inversion. The beaches will have a tough time clearing. Above
normal temps will continue inland with much cooling readings near
to the beaches.

Something rather interesting is currently forecast by both the EC
and the GFS for next Friday and Saturday. An upper low moves into
the area to the WSW of Pt Conception. It will bring plenty of
south flow into the area. Not going to anything more than bring in
partly cloudy skies to the fcst now but will have to keep a wary
eye on this time period.

&&

.AVIATION... 29/12Z...

AT 08Z AT KLAX... THE INVERSION WAS ABOUT 1250 FEET DEEP. THE TOP
WAS NEAR 3900 FEET WITH A TEMPERATURE OF 16 DEGREES CELSIUS.

OVERALL... MODERATE TO HIGH CONFIDENCE IN THE 12Z TAFS. THE
SLIGHTLY REDUCED CONFIDENCE IS DUE TO THE GENERAL UNCERTAINTY IN
MARINE INCURSION BEHAVIOR AND BECAUSE THE CATEGORY CHANGES AND
CLEARING TIMES MAY BE OFF BY +/- 1 HOUR. SOME LOCALES MAY NOT
FULLY CLEAR PRIOR TO THE MARINE INCURSION RETURNING THIS EVENING.
ISOLATED THUNDERSTORMS ARE POSSIBLE OVER THE MOUNTAINS AFTER 22Z.
OTHERWISE AND ELSEWHERE VFR CONDITIONS ARE EXPECTED.

KLAX... MODERATE TO HIGH CONFIDENCE IN THE 12Z TAF. THE SLIGHTLY
REDUCED CONFIDENCE IS DUE TO THE GENERAL UNCERTAINTY IN MARINE
INCURSION BEHAVIOR AND BECAUSE THE CATEGORY CHANGES AND CLEARING
TIMES MAY BE OFF BY +/- 1 HOUR. THERE IS A TWENTY PERCENT CHANCE
THAT MVFR CONDITIONS WILL NOT CLEAR TODAY.

KBUR... MODERATE TO HIGH CONFIDENCE IN THE 12Z TAF. THE SLIGHTLY
REDUCED CONFIDENCE IS DUE TO THE GENERAL UNCERTAINTY IN MARINE
INCURSION BEHAVIOR AND BECAUSE THE CATEGORY CHANGES AND CLEARING
TIMES MAY BE OFF BY +/- 1 HOUR. THERE IS A FIFTEEN PERCENT CHANCE
THAT MVFR CONDITIONS WILL NOT CLEAR TODAY.

&&

.MARINE... 29/230 AM...

Conditions will remain below advisory levels through at least
Thursday.  The northwest swell across the coastal waters will
diminish through the middle of the week. A long period south swell
is expected to reach the coastal waters by Tuesday then peak on
Wednesday before gradually diminishing.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&
$$

PUBLIC...Rorke
AVIATION...KJ
MARINE...KJ
SYNOPSIS...Munroe

weather.gov/losangeles




000
FXUS66 KLOX 291035
AFDLOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
335 AM PDT SUN MAY 29 2016

.SYNOPSIS...
The cut-off low pressure system currently overhead will once
again support the chance for afternoon thunderstorms across
the mountains and pushing into the Antelope Valley on Sunday.
High pressure aloft will build in behind into the area by the
middle of next week, supporting much warmer conditions that
will likely persist into next weekend.

&&

.SHORT TERM...(TDY-TUE)

The marine layer is 2500 feet deep and capped by a fairly strong
inversion. Marine layer stratus covers almost all of the coasts
and vlys. Good offshore trends are forecast today as an upper low
moves directly over the area. The offshore trends will allow for
slightly better and slightly faster clearing today compared to
yesterday. There is some uncertainty with this line of thinking
as there are currently onshore trends. If the pressure gradient
fcst is wrong then there will be slow to no clearing across the
coasts again.

The other big issue of the day is the thunderstorm chances. The
upper low and its associated destabilizing cool pool of air aloft
will be overhead this afternoon right at peak heating. This will
make today more unstable than yesterday...but there will be less
PVA today then ydy when the low was just to the west. Without the
PVA there may not be trigger to start the initial lift that will
allow the atmosphere to exploit the instability. Still there is
likely enough differential mtn slope heating in the mtns to kick
off some development. If TSTMs do get started then their outflows
will trigger more TSTMs in sort of an atmospheric chain reaction.
Any TSTMs that do form will be slow moving so the greatest threat
today will be flash flooding but there is not that much water to
work with and the TSTMs should be pretty short lived so the flash
flood threat is on the lower side of things.

The deep marine layer and the falling hgts caused by the upper low
will combine to produce cooler temps than normal...again.

There is a non zero chance that the outflows from the afternoon`s
and evening`s convection will mix the marine layer up a bit...but
its more likely that that will not happen and that there will be
a solid marine layer again tonight.

There should be good onshore trends on Monday and this will result
in another cloudy and cool day across most of the coasts with much
slower than normal clearing in the vlys. The upper low will be too
far away to create any shower threat but partly cloudy skies will
likely develop over the mtns in the afternoon due to sunshine and
some residual low level moisture.

A ridge builds in on Tuesday and hgts climb up to 582 DM. This
kind of warming aloft will really strengthen and squash the
inversion. The lower marine layer depth will not allow as many
clouds into the vlys as previous mornings but the very strong
inversion will be hard to bust up and again many beaches may stay
cloudy. Max temps will leap to above normal readings while coastal
and esp beach temperatures will hardly change at all.

.LONG TERM...(WED-SAT)

The ridge will persist over the area Wed and Thu. Both days will
resemble Tuesday with a shallow marine layer capped by a strong
inversion. The beaches will have a tough time clearing. Above
normal temps will continue inland with much cooling readings near
to the beaches.

Something rather interesting is currently forecast by both the EC
and the GFS for next Friday and Saturday. An upper low moves into
the area to the WSW of Pt Conception. It will bring plenty of
south flow into the area. Not going to anything more than bring in
partly cloudy skies to the fcst now but will have to keep a wary
eye on this time period.

&&

.AVIATION...

29/0600Z

At 0535Z at KLAX the marine layer was 1500 feet deep. The
inversion top was at 2600 feet with a temp of 17 degrees C.

Good confidence in TAFs. Cat changes and clearing times may be
off by +/- 1 hour. There will be isolated TSTMs over the mtns aft
22Z.

KLAX...Good confidence in TAF. There is a 20 percent chc of VFR
conds aft 21Z.

KBUR...Good confidence in TAF. IFR/MVFR transitions and clearing
could occur +/- 1 hour from fcst time.

&&

.MARINE...

29/230 AM

Conditions will remain below advisory levels through at least
Thursday.  The northwest swell across the coastal waters will
diminish through the middle of the week. A long period south swell
is expected to reach the coastal waters by Tuesday then peak on
Wednesday before gradually diminishing.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...Rorke
AVIATION...Rorke
MARINE...KJ
SYNOPSIS...Munroe

weather.gov/losangeles




000
FXUS66 KMTR 291028
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
328 AM PDT SUN MAY 29 2016

.SYNOPSIS...Slightly cooler weather is forecast for today,
especially near the coast where there will be areas of low clouds
and fog. A warming trend is then expected for Memorial Day and
Tuesday. Warmer than normal temperatures will continue through the
end of the week. Dry weather will persist.

&&

.DISCUSSION...As of 3:25 AM PDT Sunday...Coastal low clouds and
fog have been gradually developing northward up the coast
overnight. By 3 am fog and low clouds had reached the Golden
Gate. The north-to-south surface pressure gradient from ACV to
SFO has been slowly decreasing since yesterday, but currently
remains relatively robust at 5.8 mb. Thus, there will probably be
limited additional northward development of fog/low clouds by
sunrise...and little inland development from San Francisco Bay is
expected. Farther to the south...low clouds and fog have developed
well inland from Monterey Bay.

Fort Ord profiler data reveals an increase in the depth of the
marine layer from less than 1000 feet to more than 1500 feet over
the past 24 hours. The deeper marine layer, along with a trend
towards stronger onshore flow, will mean cooler weather for our
region today. Afternoon highs will be as much as ten degrees
cooler at the coast, with more modest cooling expected inland.
Sunny conditions will develop in most areas by midday. However,
some coastal spots, mainly south of the Golden Gate, will see only
partial clearing at best.

Warming is expected on Memorial Day and on into Tuesday as an
upper ridge builds over California, compressing the marine layer.
In addition, onshore flow will decrease by Monday. There should be
more widespread afternoon clearing in coastal areas on Memorial
Day. However, a few persistent fog patches can`t be ruled out.

The upper ridge axis is forecast to move to our east by midweek
as an upper trough develops off the west coast along 135W. This
should result in slight cooling on Wednesday and Thursday.
However, temperatures are expected to remain above normal through
the week. And, the models indicate that temperatures will climb
higher once again on Friday as the upper ridge to our east
strengthens. The ECMWF MOS indicates the most pronounced warming
late in the week, with SFO forecast to reach 82 on Friday and
Livermore 102.

The models agree that a weak upper low will develop off the
southern California coast late in the week and then lift gradually
to the northeast next weekend. The GFS forecasts precip across the
southeast portion of our forecast area by Saturday morning as the
low approaches. The ECMWF maintains dry conditions in all areas
until the following Monday night. Given these model differences
and the fact that this precipitation potential is still out at
day seven and beyond, will hold off on adding any explicit mention
of shower chances to the forecast just yet.

&&

.AVIATION...as of 10:35 PM PDT Saturday...Strong n-s gradients
persisting keeping stratus well away from the SFO Bay Area and
is presently confined to the MRY Bay Area south. Forecast remains
unchanged with stratus expected after 12z but confidence is waning
on whether cigs will get into SFO at all.

Vicinity of KSFO...MVFR cigs after 12Z possibly later. Confidence
is not high as stratus could stay out all night.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...MVFR/IFR through 17z.

&&

.MARINE...as of 2:19 am PDT Sunday...High pressure over the
eastern Pacific and low pressure inland will result in gusty
northerly winds today and tonight. Winds will be strongest over
the outer waters, especially north of Point Reyes. Winds will
gradually decrease on Memorial Day with weakening high pressure. A
building southerly swell is anticipated to arrive late Monday into
Tuesday.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...SF Bay from 12 PM
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm

&&

$$

PUBLIC FORECAST: Dykema
AVIATION: W Pi
MARINE: W Pi


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000
FXUS66 KLOX 290603
AFDLOX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
1100 PM PDT SAT MAY 28 2016

Updated Aviation Discussion

.SYNOPSIS...
The cut-off low pressure system currently overhead will once
again support the slight chance for afternoon thunderstorms
across the mountains and pushing into the Antelope Valley on
Sunday. High pressure aloft will build into the area by the
middle of next week, supporting much warmer conditions that
will likely persist into next weekend.

&&

.UPDATE...

A weak upper low just to the west of Point Conception was in a
good position to rotate a weak lobe of PVA into SBA county this
afternoon. The lift from the PVA interacted with weak instability
over the interior sections to spawn about a half dozen TSTMs. The
TSTMs were short lived pulse storms that likely produced brief
heavy downpours and perhaps some small hail.

The marine layer was slow to clear today and there was no clearing
across the south facing beaches of LA and VTA counties as well as
the central coast. The Marine layer stratus deck will slowly
reform overnight and by dawn low clouds will again cover the
coastal and vly areas.

Moderate onshore flow and the late clearing kept max temps several
degrees blo normal across the coasts and vlys but 574 DM hgts and
plenty of sunshine allowed the interior to warm to near normal
temps.

Forecast is in good shape and no updates are planned. The big
question mark is tomorrow afternoon`s convection. The upper low
will sit right atop of the area. This will mean better instability
but less in the way of low level dynamics. Given the very steep
sun angle think that there will be enough differential heating to
kick of some storms.

&&

.SHORT TERM...(SAT-TUE)

The weak upper level low will drift se across the forecast area
tomorrow morning, then into sern CA for Sun afternoon. An e-w
oriented upper level trof will linger over srn ca Sun night and
Mon, while at the same time upper level ridging builds into
central and nrn CA. The upper ridge will expand into swrn ca Mon
night and Tue.

The marine layer pattern will continue over the next few days, with
the inversion forecast to gradually strengthen and lower each day,
most pronounced Mon night and Tue as the upper ridge builds in and
boundary layer temps warm up. Extensive night and morning low clouds
and fog can be expected to affect the coast and adjacent vlys
tonight thru Tue morning, altho the inland extent of the low clouds
will diminish considerably Mon night due to the shrinking marine
inversion. There will be the possibility of afternoon cu buildups in
the mtns Sun thru Mon, but for Sun there should continue to be
enough moisture and instability for the formation of isolated
showers or thunderstorms in far sern SLO County, Cuyama Vly, the
mtns of SBA/VTU/L.A. Counties and in the Antelope Vly. Any
thunderstorms that develop could drift s into the adjacent vlys over
VTU/L.A. Counties as well by late Sun afternoon or early evening.
The 12Z NAM does indicate the best chance of thunderstorms Sun
afternoon to be over eastern San Gabriel Mtns, but even so a slight
chance of showers and thunderstorms is in the forecast for all of
the above mentioned areas. Otherwise, mostly clear skies are
expected over the forecast area for the most part Sun thru Tue. A
typical onshore flow pattern is expected each afternoon and evening,
with locally gusty sw to nw winds for the foothills, mtns and
Antelope Vly.

Temps for Sun are forecast to be generally 3 to 6 deg below normal
for the cst and adjacent vlys, while inland vlys, mtns and deserts
will be near normal to slightly above seasonal norms. For Mon, temps
will warm a few degrees, especially in the interior areas, mtns and
deserts, where highs should be 4 to 10 deg above normal. For the
coastal plain, Santa Ynez Vly, and vlys of VTU/L.A. Counties, highs
on Mon will be 2 to 6 deg below normal overall. It`ll be warmer
still for Tue with many areas away from the coastal plain warming to
4 to 12 deg above normal. Highs in the warmest vlys on Tue should
reach the upper 80s to mid 90s.


.LONG TERM...(WED-SAT)

The EC and GFS are in decent agreement Wed and Thu with upper
ridging over the area. For Fri and Sat, the EC keeps the fcst area
on the w side of a large upper ridge, while the GFS brings a broad
upper trof to the CA cst Fri, then upper troffiness moves over the
area thru Sat while a weak upper low swings into nrn Baja from the e
Pac. Either solution will keep dry and warm conditions over swrn CA
thru the extended period. Night and morning marine layer clouds will
continue to affect mainly coastal areas Wed, then be confined to the
L.A. County coast Thu thru Sat. Otherwise, mostly clear skies will
prevail across the region Wed thru Sat. There will continue to be
typical onshore flow afternoon and evening hours, with locally gusty
sw to nw winds in the foothills, mtns and deserts.

Temps will warm to about 5 to 12 deg above normal for many areas
away from the coastal plain Wed thru Fri, with slight cooling
expected on Sat. The warmest days should be Thu and Fri, with highs
in the warmest vlys and foothills reaching the upper 80s to mid 90s,
except mid to upper 90s in the Antelope Vly.

&&

.AVIATION...

29/0600Z

At 0535Z at KLAX the marine layer was 1500 feet deep. The inversion
top was at 2600 feet with a temp of 17 degrees C.

Good confidence in TAFs. Cat changes and clearing times may be off
by +/- 1 hour. There will be isolated TSTMs over the mtns aft 22Z.

KLAX...Good confidence in TAF. There is a 20 percent chc of VFR
conds aft 21Z.

KBUR...Good confidence in TAF. IFR/MVFR transitions and clearing
could occur +/- 1 hour from fcst time.

&&

.MARINE...

28/900 PM PDT

Sub small craft advisory level short period waves currently across
portions of the outer waters will gradually diminish overnight.
Small craft conditions for winds or seas are not currently
expected through at least Thursday. The northwest swell currently
across the coastal waters is expected to gradually diminish
through the middle of next week. A long period south swell is
expected to reach the coastal waters by Tuesday, peaking
Wednesday, before gradually diminishing.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
CA...NONE.
PZ...NONE.

&&

$$

PUBLIC...JS/Rorke
AVIATION...Rorke
MARINE...Munroe/30
SYNOPSIS...Munroe

weather.gov/losangeles




000
FXUS66 KMTR 290400
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
900 PM PDT SAT MAY 28 2016

.SYNOPSIS...Dry weather is forecast through the Memorial Day
weekend and through the end of next week. Slight cooling will
occur on Sunday, mainly near the coast. A warming trend is then
expected on Memorial Day and Tuesday. Temperatures are then
expected to remain above normal through the end of next week.

&&

.DISCUSSION...As of 9:00 PM PDT Saturday...Saturday was a warm
day with afternoon highs anywhere from 5 to 15 degrees above
normal. Fog was present along the coast from the Monterey
Peninsula southward, but otherwise most areas experienced sunny
conditions. A weak upper trough moving inland across central and
southern California triggered widespread afternoon and early
evening thunderstorms over the Sierra Nevada, and also produced an
isolated thunderstorms over far southeastern Monterey County at
about 6 pm this evening.

Fog and low clouds remain confined primarily to the Monterey
County coast this evening. Both the NAM and WRF models indicate
increasing coastal fog and low clouds farther north up the coast
overnight. However, given the current robust 6.6 mb north-to-
south surface pressure gradient from ACV to SFO, it`s not likely
fog will develop much farther north than the Golden Gate overnight,
nor will there likely be much development inland from SF Bay. A
forecast update was recently completed to reduce the amount of
inland low clouds and fog late tonight and Sunday morning,
particularly in the East and South Bay.

The models agree on modest cooling for Sunday as onshore flow
increases. Most significant cooling is expected near the coast
where afternoon highs may be as much as 10 degrees cooler than
today.

An upper level ridge over the Eastern Pacific is forecast to build
across California beginning on Monday...resulting in a warming
trend from Memorial Day into Tuesday. Night and morning fog and
low clouds will become less extensive and confined primarily to
areas near the ocean on these two day as the marine layer
compresses.

The upper ridge is forecast to shift to our east by the middle of
next week as an upper trough develops offshore. This will likely
result in a pause in the warming trend for a few days...and
perhaps even slight cooling on Wednesday and Thursday. In any
case, temperatures are projected to remain warmer than normal
through the end of the week.

Both the GFS and ECMWF models indicate the potential for isolated
showers or thunderstorms by next weekend as an upper low
approaches the central/southern California coast.

&&

.AVIATION...as of 5:15 PM PDT Saturday...Strong northerly gradient
is keeping stratus from the Mry Bay Area south. This is expected
to weaken tonight allowing stratus into the SFO Bay Area late
tonight well after the airport evening rush.

Vicinity of KSFO...MVFR cigs after 10Z possibly later.
West winds to 18 kt through 04z.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...Stratus has pulled back from the bay so
it will remain vfr for a while longer. Cigs expected to fill in
after sunset with mvfr cigs by 05z.

&&

.MARINE...as of 2:31 pm PDT Saturday...Gusty northwest winds are
expected to prevail over the waters through the weekend. Winds
will be strongest across the outer coastal waters. These gusty
winds will generate steep fresh swell and choppy sea conditions.
Winds are anticipated to ease beginning early next week with
improving sea conditions. Meanwhile, a building southerly swell is
anticipated to arrive early next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tngt...SCA...Pt Arena to Pigeon Pt 10-60 nm
             SCA...Pt Arena to Pt Reyes 0-10 nm
             SCA...Pigeon Pt to Pt Piedras Blancas 10-60 nm

&&

$$

PUBLIC FORECAST: Dykema
AVIATION: W Pi
MARINE: Larry


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000
FXUS66 KHNX 282252
AFDHNX

Area Forecast Discussion
National Weather Service San Joaquin Valley - Hanford CA
352 PM PDT SAT MAY 28 2016

.SYNOPSIS...
Mountain showers and thunderstorms today and Sunday as a weak upper
level low moves south along the coastline. High pressure will move
in beginning Memorial Day bringing a return to drier and much warmer
conditions through next week.

&&

.DISCUSSION...
A warming trend continues across interior central California
today, with 24 hr temperature trends currently running up around
2-4 degrees. Highs are on track to top out a few degrees above
climo this afternoon. A weak upper level disturbance moving into
the central coast is helping to generate some convection over the
higher elevations. Radar loops indicate scattered showers and a
few thunderstorms developing over the Sierra zones and a few cells
popping over the mountains of Kern County.

This weak low is progged to drop south along the California coast
through tonight and swing inland over southern California Sunday.
Convection will continue over the mountains through the evening,
with a few remnants possibly straying into the foothills in the
southerly steering flow. Expect similar convective conditions
Sunday as the disturbance swings inland, while the general warmup
continues across the area.

An upper level ridge will begin to build in behind the exiting
shortwave trough and Memorial Day will see a bit more warming,
with convection limited to a few cells near the Sierra crest.
The ridge will continue to build overhead through the middle of
next week and temperatures will hit triple digits at most Valley
locations by Tuesday, even warmer by a degree or so Wednesday.

Models begin to slightly weaken and displace the ridge by
Thursday as another pacific upper trough develops. There is not
much model consistency with the evolution of this feature. Current
indications suggest there will be little relief from our heat for
the latter part of next week and the forecast keeps temperatures
well above normal during the period, with no precipitation expected.

&&

.AVIATION...
Areas of MVFR and local IFR in showers and isolated thunderstorms
can be expected over the mountains through 04z Sunday and again
after 18z Sunday. Otherwise, VFR conditions will prevail over the
central California interior during the next 24 hours.

&&

.AIR QUALITY ISSUES...
ON SUNDAY MAY 29 2016... Unhealthy for sensitive groups in Kern
and Tulare Counties.
Further information is available at Valleyair.org

&&

.CERTAINTY...

The level of certainty for days 1 and 2 is high.
The level of certainty for days 3 through 7 is medium.

Certainty levels include low...medium...and high. Please visit
www.weather.gov/hnx/certainty.php for additional information
an/or to provide feedback.

&&

.HNX Watches/Warnings/Advisories...
NONE.
&&

$$

public...JEB
avn/fw...Bean
synopsis...WP

weather.gov/hanford



  [top]

000
FXUS66 KSGX 282143
AFDSGX

AREA FORECAST DISCUSSION
National Weather Service San Diego CA
243 PM PDT SAT MAY 28 2016

.SYNOPSIS...
A trough over northern into central California will dig in across
Southern California on Sunday, departing the area on Monday. This
will lead to a slight chance of showers over the mountains late
this afternoon and along the coast and inland valleys overnight
tonight through early Sunday as the lower levels become nearly
saturated. A ridge will build into the area through mid week with
dry weather and temps rising over inland areas, becoming hot in
the deserts.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

Main potential impacts in the short term for our area are rip
currents along the beaches and the potential for lightning strikes
over the mountains/upper desert region Sunday afternoon. Neither
risk is high, but with so many people out and about it is worth
highlighting.

Uncertainty is high in whether or not showers will develop
anywhere in the mountains this afternoon. Hi-res models have
backed off mostly on this idea. However, a look outside does show
some cumulus building over portions of the mountains, so will
leave a slight chance of showers in the forecast in the mountains
through early this evening.

Hi-res model consensus shows isolated showers developing along the
coast and into the inland valleys overnight through Sunday
morning. Point forecast soundings off the WRF show conditions
becoming nearly saturated below the inversion. For this reason,
have added in a slight chance of showers for the coast and inland
valleys late tonight through Sunday morning.

The forecast trend for the day Sunday will be for any showers to
re-focus over the mountains and perhaps the upper deserts Sunday
afternoon as convergence/lift is favored there by afternoon.
Marginal instability could lead to isolated thunderstorms as well.

The trough/upper low will pull away from the area on Memorial Day
with a transition to ridging Tue-Thu. This will lead to dry
conditions along with increasing temps inland, with 90F+ Wed-Thu
over the Inland Empire and 100F+ over the Coachella Valley. High
confidence on this, but low confidence in whether it will get
excessively hot in the Coachella Valley (possible per ECMWF), and
how long the ridge will hold next week as the trough-ridge
placement from the GFS and ECMWF differ vastly. The latest GFS
brings another trough in by Thu, moving slowly over SoCal through
next weekend, while the ECMWF locks in the ridge tight locally,
keeping the next Pacific trough at bay and really pumping temps up
in the Coachella Valley. Coastal locales will not see nearly the
temp change, remaining relatively cool due to the continued
influence of the cool waters off the Pacific. Thus, am forecastinga
temp difference from the coast to the lower deserts (~70 miles) of
nearly 40F degrees by the middle part of next week! /Gregoria

&&

.AVIATION...
282030Z...Coast/Valleys...Areas of low clouds with bases 2000-2500
ft MSL and tops to 3000 ft MSL currently in the process of clearing.
Clearing will continue for the next 3-5 hrs and coastal TAF sites
should clear, but low clouds will likely linger at the beaches this
afternoon. Low cloud cigs return to coastal TAF sites this evening
after 02Z, spreading inland overnight with bases around 2000 ft MSL.
A Slight chance of showers overnight through Sunday morning.

Mountains/Deserts...SCT-BKN080-100 with isolated shra over the
mountains this afternoon, dissipating by 02Z Sunday. Unrestricted
vis will prevail, except with brief showers. Otherwise SCT clouds at
or above 8000 ft msl with unrestricted vis through Sun morning.

&&

.MARINE...
130 pm...No hazardous marine conditions are expected through
Wednesday.

&&

.SGX Watches/Warnings/Advisories...
CA...None.
PZ...None.
&&

$$

PUBLIC...Gregoria
AVIATION/MARINE...PG




000
FXUS66 KMTR 281752
AFDMTR

Area Forecast Discussion
National Weather Service San Francisco Bay Area
1052 AM PDT SAT MAY 28 2016

.SYNOPSIS...A dry and warm Memorial Day weekend is forecast for
the Bay Area. The trend will continue at least through the middle
of next week with no significant cooling expected until late in
the week at the earliest.

&&

.DISCUSSION...as of 8:52 AM PDT Saturday...Visible satellite
imagery shows only a few low clouds over the northern Monterey
Bay and along the Monterey coastline. There are high clouds over
much of northern California. Morning temperatures are running
warmer than yesterday at this time by several degrees as readings
are ranging from the mid 50s to lower 60s across the district.
Highs today will be warmer than those on Friday with mid to upper
60s at the immediate coast, and 70s, 80s and even 90s well inland.

The 12Z NAM is still indicating a southerly stratus surge on
Sunday, and stratus can already be seen creeping up the coast on
visible satellite. and eddy has formed just west of Cambria due to
differing air flows in that area. The NAM brings low clouds up the
coast to San Francisco by 09Z and along the entire coast by Sunday
morning. This will put a limit on coastal warming for tomorrow,
and an onshore flow will also bring some cooler temps locally
inland. This slight cooling trend is expected to be short lived as
high pressure aloft rebuilds over California. Warmer temperatures
are forecast for Memorial Day and Tuesday, with the upper ridge
slowly edging east over the great basin through the rest of the
week.

&&

.AVIATION...as of 10:52 AM PDT Saturday...Mostly clear skies are
being reported across the forecast area this morning. However, the
current visible satellite image is showing a southerly surge
pushing up the Big Sur coast. The southerly surge will make it
into Monterey bay this afternoon and will impact Salinas and
Monterey by early evening. The big question is how much stratus
will make it into San Francisco bay and when. At this point have
stratus in San Francisco bay for a brief period early Sunday
morning.

Vicinity of KSFO...VFR conditions are expected to prevail through
late tonight with MVFR conditions possible between 1000Z and
1400Z Sunday morning. The sea breaze is expected to reach 18 kt
this afternoon.

Confidence is high.

SFO Bridge Approach...Similar to KSFO.

Monterey Bay Terminals...VFR conditions are expected to prevail
through this afternoon with MVFR returning around 0500z. The sea
breeze is expected to reach 10 to 12 kt this afternoon.

Confidence is moderate.

&&

.MARINE...as of 10:43 AM PDT Saturday...A broad thermal trough
will maintain gusty northwest winds over the waters through the
weekend...winds will be strongest across the outer coastal waters.
Additionally...steep fresh swell and choppy conditions will be
generated by these winds. The gusty winds and fresh seas gradually
subside early next week. Meanwhile...a building southerly swell
is anticipated to arrive early next week.

&&

.MTR WATCHES/WARNINGS/ADVISORIES...
     .Tday...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...SF Bay from 2 PM

&&

$$

PUBLIC FORECAST: Sims
AVIATION: Larry
MARINE: Larry


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