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000
FXUS66 KSTO 292222
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
322 PM PDT FRI APR 29 2016

.Synopsis...
A chance of showers over the Sierra this evening through Saturday,
with light snow accumulations. Thunderstorms possible over the
Sierra Sunday afternoon and evening. Breezy north winds developing
this evening through Saturday. Above normal daytime temperatures
through mid week. Cooler with showers and thunderstorms possible
next Thursday and Friday.

&&

.Discussion...
High pressure ridging today will give way as an upper level shortwave
with a surface cold front moves southward. Moisture is limited,
BUT some showers have begun developing over Shasta County and into
the Sierra. A few thunderstorms could pop up in those areas into
this evening, so have added them to the forecast. The Sierra
south of I80 could see around an inch of snow at and above pass
levels.

Dry, warm, and sunny weather is expected on Saturday, except for a
few lingering showers over the Sierra crest south of Highway 50.

The main issue tonight and Saturday is wind. Winds will be shifting
to the north by this evening. Surface high pressure will build
over Oregon, with the pressure gradient tightening and winds
increasing. Winds will increase tonight and become breezy, with
windy conditions on Saturday, especially on the west side of the
Valley and over the Coastal Range. A Wind Advisory remains in
effect from 11 pm tonight to 5 pm Saturday.

Another disturbance drops down Sunday, and this will bring the
potential for mountain showers and thunderstorms in the afternoon
and evening. Some breezy north to east winds continue, but will be
quite a bit weaker than the Saturday winds. Highs in the Valley
should peak into mid 80s. EK

&&

.EXTENDED DISCUSSION (Tuesday THROUGH Friday)

A cooling trend with unsettled/showery weather developing for the
EFP as the synoptic pattern is dominated by a digging offshore trof
and increasing onshore flow. Model consensus suggests the closed
upper low will slide into Socal by/around Fri.

Near normal max temps Tue/Wed are forecast to cool several degrees
below normal Thu/Fri especially over the Srn portion of our CWA...
which is closer to the core of the upper low over Socal. Synoptic
pattern suggests chance of showers increases during the EFP as
cyclonic flow increases over Norcal. Possible T-storms mainly
over the mtns Thu/Fri as instability increases over our CWA.  JHM

&&
&&

.AVIATION...

VFR conditions over interior Norcal thru 06z Sat except for
BKN-OVC AOA 200-250 moving SEwd over the area through 21z Fri.
Upper air feature moves over Norcal tonite and Sat bringing
strong Nly winds and local MVFR/IFR conditions in -SHRA/SHSN to
the Shasta Co mtns and Siernev. Nly barrier jet winds forecast to
develop on the W side of the Valley with areas 25g40kts 06z-18z
Sat and local NE-E g45 kts winds over Siernev.


&&

.STO Watches/Warnings/Advisories...
Wind Advisory from 11 PM this evening to 5 PM PDT Saturday for
Carquinez Strait and Delta-Central Sacramento Valley-Clear
Lake/Southern Lake County-Mountains Southwestern Shasta County
to Northern Lake County-Northern Sacramento Valley-Northern San
Joaquin Valley-Southern Sacramento Valley.

&&

$$





000
FXUS66 KSTO 291644
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
944 AM PDT FRI APR 29 2016

.Synopsis...
A chance of showers over the Sierra this evening through Saturday.
Thunderstorms possible over the Sierra Sunday afternoon and
evening. Breezy north winds developing this evening through
Saturday. Showers possible most areas by next Thursday. Above
normal daytime temperatures.

&&

.Discussion...
High pressure ridging today will give way as an upper level shortwave
with a surface cold front moves southward. Moisture is limited,
though could see some showers early this evening and into tonight
over the Sierra. The Sierra south of I80 could see around an inch
of snow at and above pass levels overnight. The rest of the area
will be dry, warm, and sunny today, and this will continue into
Saturday.

The main issue over the next 2 days is wind. Winds are currently shifting
to the north over the northern Sacramento, and this shift will
move down the Valley behind the cold front. Surface high pressure
will build over Oregon, with the north to south surface pressure
gradient tightening and winds increasing. Winds will increase
tonight and become breezy, with windy conditions on Saturday,
especially on the west side of the Valley and over the Coastal
Range as a barrier jet develops. A Wind Advisory remains in
effect from 11 pm tonight to 5 pm Saturday.

Another disturbance drops down Sunday, and this will bring the
potential for mountain showers and thunderstorms in the afternoon
and evening. Some breezy north to east winds continue, but will be
quite a bit weaker than the Saturday winds. EK

&&

.EXTENDED DISCUSSION (Tuesday THROUGH Friday)

Upper low in EPAC slowly approaches NorCal Tuesday into Wednesday
bringing synoptic cooling and a threat of showers over the
mountains. Models differ with track of low but pattern suggests
increased potential for showers over Interior NorCal Thursday
into Friday with possible afternoon thunderstorms over the
mountains.

&&
&&

.AVIATION...

VFR conditions over interior Norcal thru 06z Sat except for
BKN-OVC AOA 200-250 moving SEwd over the area through 21z Fri.
Upper air feature moves over Norcal tonite and Sat bringing
strong Nly winds and local MVFR/IFR conditions in -SHRA/SHSN to
the Shasta Co mtns and Siernev. Nly barrier jet winds forecast to
develop on the W side of the Valley with areas 25g40kts 06z-18z
Sat and local NE-E g45 kts winds over Siernev.


&&

.STO Watches/Warnings/Advisories...
Wind Advisory from 11 PM this evening to 5 PM PDT Saturday for
Carquinez Strait and Delta-Central Sacramento Valley-Clear
Lake/Southern Lake County-Mountains Southwestern Shasta County
to Northern Lake County-Northern Sacramento Valley-Northern San
Joaquin Valley-Southern Sacramento Valley.

&&

$$





000
FXUS66 KSTO 290951
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
251 AM PDT FRI APR 29 2016

.Synopsis...
A chance of showers over the Sierra this evening through Saturday.
Thunderstorms possible over the Sierra Sunday afternoon and
evening. Breezy north winds developing this evening through
Saturday. Showers possible most areas by next Thursday. Above
normal daytime temperatures.

&&

.Discussion...
High pressure over the west coast bringing fair skies most areas
this morning. Early morning temperatures are running a bit warmer
than 24 hours ago. A weak frontal band now moving into the Pacific
Northwest is bringing some cloud cover to the far north state this
morning. This system is forecast to clip the north state today
dropping into the Great Basin by Saturday morning. A few showers
may be possible over the Sierra this evening but with high snow
levels and minimal QPF, impacts over the Sierra will be minimal.
The weak system will likely not even have much impact on daytime
highs today with max temperatures remaining above normal. Surface
high pressure pushing in behind todays system combined with
northerly flow aloft will produce breezy north winds tonight and
Saturday. The strongest winds are expected along the west side of
the Sacramento valley and coastal range. A wind advisory will be
issued for late tonight and Saturday for this area. These winds
should drop off by Saturday night and early Sunday as high
pressure aloft pushes in over the west coast. The low over the
southern Great Basin is expected to remain in place however with
the GFS, ECMWF and GEM models all pivoting an upper shortwave
westward around the top of the low and into eastern California on
Sunday afternoon. Models show enough instability for a threat of
thunderstorms over the northern Sierra into the evening hours.
Elsewhere will remain dry with warming temperatures on Sunday.
Wrap around moisture from the Great Basin low will continue to
bring a threat of showers over the Sierra Cascade range on Monday
while the remainder of the forecast area remains dry with slightly
lower daytime highs.

&&

.EXTENDED DISCUSSION (Tuesday THROUGH Friday)

Upper low in EPAC slowly approaches NorCal Tuesday into Wednesday
bringing synoptic cooling and a threat of showers over the
mountains. Models differ with track of low but pattern suggests
increased potential for showers over Interior NorCal Thursday
into Friday with possible afternoon thunderstorms over the
mountains.

&&

.AVIATION...

NWly flow alf as upr low movs acrs NE CA this aftn into Sat. VFR
conds for Intr NorCal nxt 24 hrs exc lcl MVFR/IFR conds poss in
shwrs acrs NE and E mtns tngt into Sat. Areas of Nly sfc wnd gsts
to 30 kts or gtr tngt into Sat.

&&

.STO Watches/Warnings/Advisories...
Wind Advisory from 11 PM this evening to 5 PM PDT Saturday for
Carquinez Strait and Delta-Central Sacramento Valley-Clear
Lake/Southern Lake County-Mountains Southwestern Shasta County
to Northern Lake County-Northern Sacramento Valley-Northern San
Joaquin Valley-Southern Sacramento Valley.

&&

$$





000
FXUS66 KSTO 290439
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
939 PM PDT THU APR 28 2016

.Synopsis...
Breezy north winds today then again over the weekend, peaking
Saturday. Isolated showers and thunderstorms over the northern
Sierra today and through the weekend. Otherwise dry with above
normal temperatures through Sunday. Another wave drops down from
the north

&&

.Discussion...
High pressure with clear skies this evening over Northern
California will give way to a low pressure area that will drop
into Nevada on Friday night. This will bring some clouds and
cooling to the area Friday with isolated showers possible over the
mountains late in the afternoon.

The center of the low will move into Western Nevada Friday night
and moisture wrapping around the low may bring some showers to the
Sierra Nevada. Snow levels look high above pass level until late
at night and Saturday morning. Windy conditions look to develop
in the valley on Saturday and then taper Saturday evening. The
mountains looks like they could see some decent northeast winds
Saturday night.  Any lingering precipitation will be moving south
of the area by late morning.

On Sunday their is a weak wave that forms over Northern Nevada
on the northeast side of the low that will have moved to near the
four corners area. Winds will be much lighter but some additional
showers may occur over the Sierra near the crest. There may be
enough instability on Sunday for some thunderstorms to develop
over the Sierra Nevada.

&&

.EXTENDED DISCUSSION (Monday THROUGH Thursday)

Sunday`s Rex Block near the Four-Corners is forecast to break down
by Mon...with upper ridging building over Norcal. Steering flow
forecast to become SWly which should preclude precip or any thunder
chances in our CWA...while there is a chance E of the Sierra Crest
along the deformation zone extending Wwd across the Great Basin.

Warmer than normal max temps continue Mon/Tue...then a cooling trend
with unsettled/showery weather developing for the middle of the week.
Synoptic cooling from the digging offshore trof and increasing onshore
flow will cool max temps to several degrees below normal Wed/Thu.
Although there are model differences...synoptic pattern suggests
chance of showers increases Wed/Thu as cyclonic flow increases
over Norcal with possible T-storms over the coastal range Thu. JHM

&&
&&

.AVIATION...

VFR conditions for TAF sites thru Fri. North to Northwesterly
winds at TAF sites with gusts up to 25 kts. Winds less than 10
kts overnight into Friday. Winds will transition Friday afternoon
becoming more West to Southwesterly with locally breezy conditions
possible in the afternoon. JBB
&&

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

$$





000
FXUS66 KSTO 290439
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
939 PM PDT THU APR 28 2016

.Synopsis...
Breezy north winds today then again over the weekend, peaking
Saturday. Isolated showers and thunderstorms over the northern
Sierra today and through the weekend. Otherwise dry with above
normal temperatures through Sunday. Another wave drops down from
the north

&&

.Discussion...
High pressure with clear skies this evening over Northern
California will give way to a low pressure area that will drop
into Nevada on Friday night. This will bring some clouds and
cooling to the area Friday with isolated showers possible over the
mountains late in the afternoon.

The center of the low will move into Western Nevada Friday night
and moisture wrapping around the low may bring some showers to the
Sierra Nevada. Snow levels look high above pass level until late
at night and Saturday morning. Windy conditions look to develop
in the valley on Saturday and then taper Saturday evening. The
mountains looks like they could see some decent northeast winds
Saturday night.  Any lingering precipitation will be moving south
of the area by late morning.

On Sunday their is a weak wave that forms over Northern Nevada
on the northeast side of the low that will have moved to near the
four corners area. Winds will be much lighter but some additional
showers may occur over the Sierra near the crest. There may be
enough instability on Sunday for some thunderstorms to develop
over the Sierra Nevada.

&&

.EXTENDED DISCUSSION (Monday THROUGH Thursday)

Sunday`s Rex Block near the Four-Corners is forecast to break down
by Mon...with upper ridging building over Norcal. Steering flow
forecast to become SWly which should preclude precip or any thunder
chances in our CWA...while there is a chance E of the Sierra Crest
along the deformation zone extending Wwd across the Great Basin.

Warmer than normal max temps continue Mon/Tue...then a cooling trend
with unsettled/showery weather developing for the middle of the week.
Synoptic cooling from the digging offshore trof and increasing onshore
flow will cool max temps to several degrees below normal Wed/Thu.
Although there are model differences...synoptic pattern suggests
chance of showers increases Wed/Thu as cyclonic flow increases
over Norcal with possible T-storms over the coastal range Thu. JHM

&&
&&

.AVIATION...

VFR conditions for TAF sites thru Fri. North to Northwesterly
winds at TAF sites with gusts up to 25 kts. Winds less than 10
kts overnight into Friday. Winds will transition Friday afternoon
becoming more West to Southwesterly with locally breezy conditions
possible in the afternoon. JBB
&&

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

$$





000
FXUS66 KSTO 282243
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
343 PM PDT THU APR 28 2016

.Synopsis...
Breezy north winds today then again over the weekend, peaking
Saturday. Isolated showers and thunderstorms over the northern
Sierra today and through the weekend. Otherwise dry with above
normal temperatures through Sunday. Another wave drops down from
the north

&&

.Discussion...
There has been a big change in the weather today, with mainly
sunny, dry and much warmer temperatures. Some showers and
thunderstorms are developing this afternoon over the Sierra and
Motherlode, with the back end of the upper low still wrapping some
moisture and instability. This convection is expected to be
isolated and short lived before ending by this evening.

Friday will be dry and slightly warmer, but this will just be a
short intermission between systems. A quick moving inside-slider
type wave will drop down over the Sierra by Friday evening. This
will bring showers over the higher Sierra, with snow showers
around 8000 feet and above.

By Saturday during the day this system will be dropping to the
south of the area, with just a few lingering showers over the
Sierra south of Highway 50. Most locations will be sunny and
warmer. North winds will increase through the day, breezy and
becoming windy by afternoon in some Valley locations. Temperatures
peak on Sunday, with Valley highs in the mid 80s. North winds
continue, but not as strong as on Saturday. EK

&&

.EXTENDED DISCUSSION (Monday THROUGH Thursday)

Sunday`s Rex Block near the Four-Corners is forecast to break down
by Mon...with upper ridging building over Norcal. Steering flow
forecast to become SWly which should preclude precip or any thunder
chances in our CWA...while there is a chance E of the Sierra Crest
along the deformation zone extending Wwd across the Great Basin.

Warmer than normal max temps continue Mon/Tue...then a cooling trend
with unsettled/showery weather developing for the middle of the week.
Synoptic cooling from the digging offshore trof and increasing onshore
flow will cool max temps to several degrees below normal Wed/Thu.
Although there are model differences...synoptic pattern suggests
chance of showers increases Wed/Thu as cyclonic flow increases
over Norcal with possible T-storms over the coastal range Thu. JHM

&&
&&

.AVIATION...

VFR conditions for TAF sites thru Fri. Possible MVFR/IFR
conditions over western Sierra slopes (south of Tahoe) and
Motherlode as lingering showers persist until about 00z Fri.
North to Northwesterly winds at TAF sites with gusts up to 25 kts.
Wind gusts will diminish between 0-3z with TAF site winds being
less than 10 kts overnight through Friday morning. Winds will
transition Friday afternoon becoming more West to Southwesterly.
JBB
&&

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

$$





000
FXUS66 KSTO 281729
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1029 AM PDT THU APR 28 2016

.Synopsis...
Breezy north winds today then again over the weekend. Isolated
showers possible over the northern Sierra today and through the
weekend with a slight chance of thunderstorms there. Otherwise dry
with above normal temperatures through Sunday.

&&

.Discussion...
Mainly dry weather expected today as the upper low which brought
thunderstorms yesterday and some mountain snow overnight. Showers
wrapping around the back of the low possible through today over
the Sierra. A few isolated thunderstorms may develop over the
Motherlode this afternoon. Several meso models are showing these
centered over Caleveras and Tuolumne counties around noon to 3 pm.
Temperatures today will be much warmer this afternoon, reaching
around 80 in the Valley. Breezy north winds expected throughthe
day, gusting up to 30-35 mph. Current forecast is on track, no
update needed.

Considerable photographic, video, and eye witness evidence from
law enforcement and the public have lead us to confirm an EF0
tornado touched down in the Waterford/Hickman area yesterday
around 3:45 pm. This was a brief touch down, with relatively minor
damage.

In addition to the tornado, there were numerous funnel clouds
reported. There is no evidence that any of this touched down.
Large amounts of small hail were reported in several locations,
notably just north of Oakdale, causing damage to mobile home
carports and covering roads.

Snow fell over Sierra passes yesterday afternoon and overnight.
About an inch fell at Donner Pass Wednesday afternoon, with
another inch overnight. This caused some travel difficulties. EK

&&

.EXTENDED DISCUSSION (Monday THROUGH Thursday)

Models showing upper ridging over NorCal Monday which shifts east into
the Great Basin Tuesday as offshore upper low approaches. Upper
low progged inside of 130 W Wednesday with potential for showers
mainly over the mountains. Models differ with track of low
Thursday but overall pattern suggests deformation zone sets up
over Interior NorCal with potential for more widespread showers
and possibly isolated thunderstorms. High temperatures in the
Central Valley cool from the low to mid 80s Monday to 70s
Thursday.
&&

.AVIATION...

VFR conditions over Norcal TAF sites thru Fri. Possible MVFR/IFR
conditions over hyr elevations of the Sierra and Motherlode as
NEly (backwash) flow spreads low clouds and possible showers from
Wrn NV over the Sierra Crest til 03z Fri. Nly sfc wind gusts up to 25
kts in the Central Valley til 03z Fri.
&&

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

$$





000
FXUS66 KSTO 281051
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
351 AM PDT THU APR 28 2016

.Synopsis...
Breezy north winds today then again over the weekend. Isolated
showers possible over the northern Sierra today and through the
weekend with a slight chance of thunderstorms there. Otherwise dry
with above normal temperatures through Sunday.

&&

.Discussion...
Upper low that brought active weather to Norcal on Wednesday has
now moved eastward with its center now over the southern Great
Basin. IR Satellite shows some scattered clouds over the Sierra
Cascade crest this morning but showers remain east of the crest.
Shortwaves rotating around back side of low still may bring some
scattered showers over the northern Sierra today with enough
instability for a threat of afternoon or evening thunderstorms.
Circulation around back side of low combined with a 7 mb surface
gradient from MFR to SAC bringing breezy north winds to the
northern CWA this morning and this wind likely to spread
southward during the day although not strong enough to warrant
wind advisory. A fairly significant warm up is expected today as
upper ridging builds in along with the northerly winds with
daytime highs coming in several degrees above normal. Friday looks
mainly dry and continued warm as a small inside slider low drops
into the Pacific Northwest. This system drops into the Great Basin
on Saturday bringing just a threat of showers to the Northern
Sierra crest. The rest of the forecast area will see continued
warm and dry conditions with another round of breezy north winds
behind the low. GFS, ECMWF AND GEM all show a wave rotating
southwest around top of Great Basin low and into eastern
California on Sunday. With this model consistency, have included
chance of showers and thunderstorms along the entire Sierra
Cascade range Sunday afternoon.

&&

.EXTENDED DISCUSSION (Monday THROUGH Thursday)

Models showing upper ridging over NorCal Monday which shifts east into
the Great Basin Tuesday as offshore upper low approaches. Upper
low progged inside of 130 W Wednesday with potential for showers
mainly over the mountains. Models differ with track of low
Thursday but overall pattern suggests deformation zone sets up
over Interior NorCal with potential for more widespread showers
and possibly isolated thunderstorms. High temperatures in the
Central Valley cool from the low to mid 80s Monday to 70s
Thursday.
&&

.AVIATION...

Upr low movs into Desert SW tda as upr rdg alg W Cst blds inld. VFR
conds ovr Intr NorCal nxt 24 hrs exc isold MVFR/IFR conds poss in
shwrs ovr Siernev til arnd 03z Fri. Areas Nly sfc wnd gsts up to
25 kts poss in Cntrl Vly tda btwn 15z Thu and 02z Fri.
&&

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

$$





000
FXUS66 KSTO 280405
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
905 PM PDT WED APR 27 2016

.Synopsis...
Scattered showers over the mountains with light snow
accumulations over the higher elevations. A little breezy behind
this system on Thursday, then dry and warmer.

&&

.Discussion...
Active day earlier has been calming down throughout the evening.
Earlier Thunderstorms produced hail up to 3/4 inch was reported,
a number of funnel clouds, heavy rain that produced some local
flooding. There was also a report of a tornado touchdown near
Waterford in Stanislaus County. We haven`t been able to
confirm the touchdown as of yet but reports seem promising.

Scattered showers are lingering over the mountains but will
continue to taper overnight. The morning looks dry at this time
but Thursday afternoon some showers and possible thunderstorms may
pop up near the crest south of I-80...other than that everywhere
else looks dry, warmer and breezy.

On Friday and Friday night there will be a low pressure area that
drops down from the north and into Nevada that may bring some
showers to the western slopes including the Burney Basin. The NAM
is indicating fairly dry conditions with just isolated showers
while the GFS is a lot wetter through Saturday so some uncertainty
still exists for that area and precipitation. As a result of that
low pressure area temperatures for the interior are not expected
to change a lot through Saturday with the main warm up occurring
Thursday.

&&

.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)

A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
year.

A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.
&&

.AVIATION...

VFR conditions should persist for the next 24 hours. Shower activity
from earlier this evening has diminished in the valley so TAF
sites should remain dry although light snow showers will continue
over the Sierra tonight. Winds have also diminished and will be
around 10 kts or less overnight. North to northwest winds will
pick up tomorrow around 18z with sustained winds at TAF sites
ranging 10-15 kts and gusts up to 22 kts. Those enhanced winds
will begin to lessen after 00z Fri. JBB
&&

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

$$





000
FXUS66 KSTO 280405
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
905 PM PDT WED APR 27 2016

.Synopsis...
Scattered showers over the mountains with light snow
accumulations over the higher elevations. A little breezy behind
this system on Thursday, then dry and warmer.

&&

.Discussion...
Active day earlier has been calming down throughout the evening.
Earlier Thunderstorms produced hail up to 3/4 inch was reported,
a number of funnel clouds, heavy rain that produced some local
flooding. There was also a report of a tornado touchdown near
Waterford in Stanislaus County. We haven`t been able to
confirm the touchdown as of yet but reports seem promising.

Scattered showers are lingering over the mountains but will
continue to taper overnight. The morning looks dry at this time
but Thursday afternoon some showers and possible thunderstorms may
pop up near the crest south of I-80...other than that everywhere
else looks dry, warmer and breezy.

On Friday and Friday night there will be a low pressure area that
drops down from the north and into Nevada that may bring some
showers to the western slopes including the Burney Basin. The NAM
is indicating fairly dry conditions with just isolated showers
while the GFS is a lot wetter through Saturday so some uncertainty
still exists for that area and precipitation. As a result of that
low pressure area temperatures for the interior are not expected
to change a lot through Saturday with the main warm up occurring
Thursday.

&&

.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)

A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
year.

A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.
&&

.AVIATION...

VFR conditions should persist for the next 24 hours. Shower activity
from earlier this evening has diminished in the valley so TAF
sites should remain dry although light snow showers will continue
over the Sierra tonight. Winds have also diminished and will be
around 10 kts or less overnight. North to northwest winds will
pick up tomorrow around 18z with sustained winds at TAF sites
ranging 10-15 kts and gusts up to 22 kts. Those enhanced winds
will begin to lessen after 00z Fri. JBB
&&

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

$$





000
FXUS66 KSTO 272331
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
431 PM PDT WED APR 27 2016

.Synopsis...
Scattered showers and thunderstorms through early evening, some of
them severe. Light snow accumulations over the higher elevations
of the NorCal mountains tonight. A little breezy behind this
system on Thursday, then dry and warmer.

&&

.Discussion...
An upper level level trough with a surface cold front and cool
air aloft has brought very unstable conditions with scattered
showers and afternoon thunderstorms. As expected, Some of the
thunderstorms have dropped large amounts of small hail and heavy
rain over portions of the northern San Joaquin and southern
Sacramento Valley. Large amounts of small hail caused several mobile
home carports to collapse in Oakdale. Funnel clouds have been
observed in multiple locations. Law enforcement reports a possible
tornado touchdown near Waterford in Stanislaus County. We will be
investigating further see if there was a confirmed touchdown.

The most favorable timing for thunderstorms is winding down,
though several storms continue in the Sacramento area and
southward. Low pressure is centered over the Sacramento area, with
slow moving storms rotating around the low. Some of these storms
near Sloughhouse and Rancho Murieta have been dropping heavy rain
over a period of time. Rancho Cordova received about 0.82 inches
of rain in about an hour. Heavy rain has caused ponding on roads
in some spots and and could lead to local flooding. Motorists
should avoid driving through water; "Turn around don`t drown!"

Convection over the Valley will diminish after sunset, with some
lingering showers in the mountains. Some mountain snow is falling,
and there could be a few inches of snow over the Sierra passes
this evening. Travelers over mountain passes should use caution.

Some afternoon thunderstorms may develop over the Sierra Thursday
afternoon, mainly south of I80. Drier and much warmer temperatures
are expected elsewhere, reaching around 80 in the Valley. This
warming will continue through the weekend, with Valley highs
approaching 90 on Sunday.

EK

&&

.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)

A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
year.

A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.
&&

.AVIATION...

VFR conditions are expected at the terminals for the next 24
hour period.

Winds will be light out of the south and will generally shift to
the west or northwest direction Wednesday night after an upper
level disturbance moves through the NorCal region. There could be
a few wind gusts during the afternoon hours, mainly for the
Stockton terminal. Showers and isolated thunderstorms are
possible with the vicinity of the terminals, but confidence of
direct influence is lessening at this point with short term model
guidance keeping the Valley mostly dry.
&&

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

$$





000
FXUS66 KSTO 271701
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
1001 AM PDT WED APR 27 2016

.Synopsis...
Scattered showers and thunderstorms today. Light snow
accumulations over the higher elevations of the NorCal mountains.
A little breezy behind this system on Thursday, then dry and
warmer.

&&

.Discussion...
An upper level level trough with a surface cold front will
quickly pass through Northern California today. Cool air aloft
with this system will bring unstable conditions with scattered
showers and afternoon thunderstorms. Radar and surface
observations show scattered showers currently along the western
side of the Sacramento Valley pushing eastward. By noon there will
be the potential for showers across the forecast area.

Latest model soundings are showing significant CAPE this afternoon from
the northern Coastal Range and to the southeast through the
southern Sacramento and northern San Joaquin valleys and extending
into the Sierra. This area has the best potential for
thunderstorms, though shear looks like it will fairly limited.
This reduces the potential for stronger, rotating thunderstorms.
Most storms are expected to be more of the relatively short-lived
pulse type. The main concerns are small to moderate size hail and
locally heavy rain. With relatively dry low levels, local gusty
winds near storms could also be an issue. The most favorable
timing for thunderstorms looks like 2-5 pm. Convection over the
Valley will diminish after sunset, with some lingering showers in
the mountains.

Snow showers in the higher mountains could bring a few inches of
wet snow late this afternoon into tonight. Travelers over mountain
passes should use caution. EK
&&
.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)

A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
year.

A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.
&&

.AVIATION...

VFR conditions are expected at the terminals for the next 24
hour period.

Winds will be light out of the south and will generally shift to
the west or northwest direction Wednesday night after an upper
level disturbance moves through the NorCal region. There could be
a few wind gusts during the afternoon hours, mainly for the
Stockton terminal. Showers and isolated thunderstorms are
possible with the vicinity of the terminals, but confidence of
direct influence is lessening at this point with short term model
guidance keeping the Valley mostly dry.
&&

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

$$





000
FXUS66 KSTO 271031
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
331 AM PDT WED APR 27 2016

.Synopsis...
Scattered showers and isolated thunderstorms today. Light snow
over the higher elevations of the NorCal mountains. A little
breezy behind this system on Thursday, then dry and warmer.

&&

.Discussion...
Water vapor imagery shows incoming trough with tightly wound vort
just off the southwest coast of Oregon. A line of showers
associated with this feature is nearing the NW coast of
California. Higher resolution models continue to indicate that
scattered showers, and perhaps a few thunderstorms, will spread
inland into the northern mountains and northern Sacramento Valley
by late morning.

The models have been pretty consistent tracking the strong vort
southward toward the Bay Area and Sacramento region by 00Z, so
expect to see shower and thunderstorm chances increase in the
Sacramento metro area and northern Sierra Nevada during the
afternoon. Forecast soundings for the Sac area indicate some
pretty healthy CAPE and steep mid-level lapse rates, so moderate
size hail along with brief heavy rain and gusty winds may
accompany stronger storms late today.

An inch or two of snow will be possible later this afternoon into
this evening across the northern Sierra passes which may lead to
some travel impacts for a period of time before showers taper off
later this evening.

The low shifts east into the lower Colorado River Valley by early
Thursday with perhaps a few lingering wrap-around showers
remaining over the Sierra, mainly south of Tahoe. The remainder of
the area will return to dry and milder weather with breezy north
winds.

Dry and milder weather is expected on Friday with short-wave
ridging overhead. Another system is forecast to clip the region
Friday night as it drops southward through Nevada perhaps bringing
some showers to the northern Sierra crest.

&&

.Extended Discussion (Sunday thru Wednesday)...
A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
year.

A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.

&&

.Aviation...
VFR conditions are expected at the terminals for the next 24 hour
period.

Winds will be light out of the south and will generally shift to
the west or northwest direction Wednesday night after an upper
level disturbance moves through the NorCal region. There could be
a few wind gusts during the afternoon hours, mainly for the
Stockton terminal. Showers and isolated thunderstorms are
possible with the vicinity of the terminals, but confidence of
direct influence is lessening at this point with short term model
guidance keeping the Valley mostly dry.

&&

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

&&

$$





000
FXUS66 KSTO 271031
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
331 AM PDT WED APR 27 2016

.Synopsis...
Scattered showers and isolated thunderstorms today. Light snow
over the higher elevations of the NorCal mountains. A little
breezy behind this system on Thursday, then dry and warmer.

&&

.Discussion...
Water vapor imagery shows incoming trough with tightly wound vort
just off the southwest coast of Oregon. A line of showers
associated with this feature is nearing the NW coast of
California. Higher resolution models continue to indicate that
scattered showers, and perhaps a few thunderstorms, will spread
inland into the northern mountains and northern Sacramento Valley
by late morning.

The models have been pretty consistent tracking the strong vort
southward toward the Bay Area and Sacramento region by 00Z, so
expect to see shower and thunderstorm chances increase in the
Sacramento metro area and northern Sierra Nevada during the
afternoon. Forecast soundings for the Sac area indicate some
pretty healthy CAPE and steep mid-level lapse rates, so moderate
size hail along with brief heavy rain and gusty winds may
accompany stronger storms late today.

An inch or two of snow will be possible later this afternoon into
this evening across the northern Sierra passes which may lead to
some travel impacts for a period of time before showers taper off
later this evening.

The low shifts east into the lower Colorado River Valley by early
Thursday with perhaps a few lingering wrap-around showers
remaining over the Sierra, mainly south of Tahoe. The remainder of
the area will return to dry and milder weather with breezy north
winds.

Dry and milder weather is expected on Friday with short-wave
ridging overhead. Another system is forecast to clip the region
Friday night as it drops southward through Nevada perhaps bringing
some showers to the northern Sierra crest.

&&

.Extended Discussion (Sunday thru Wednesday)...
A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
year.

A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.

&&

.Aviation...
VFR conditions are expected at the terminals for the next 24 hour
period.

Winds will be light out of the south and will generally shift to
the west or northwest direction Wednesday night after an upper
level disturbance moves through the NorCal region. There could be
a few wind gusts during the afternoon hours, mainly for the
Stockton terminal. Showers and isolated thunderstorms are
possible with the vicinity of the terminals, but confidence of
direct influence is lessening at this point with short term model
guidance keeping the Valley mostly dry.

&&

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

&&

$$





000
FXUS66 KSTO 270417
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
917 PM PDT TUE APR 26 2016

.Synopsis...
Valley showers and isolated thunderstorms tomorrow. Light snow
accumulations at pass level. A little breezy behind this system on
Thursday, then dry and warming weather.

&&

.Discussion...
Trough of low pressure will be deepening over the region. Not much
in the way of showers is expected until the afternoon hours with
most showers occurring over the mountains at least at first.
Instability is pretty good so some thunderstorms could develop
during the afternoon and evening hours and that could bring some
activity to the valley. Snow levels look high near pass levels
during the afternoon and precipitation amounts look light so there
may not be much of an impact if travel over the passes.

The low will move into Nevada Wednesday night into Thursday. The
activity will die down with some lingering showers possible near
the crest on Thursday. Breezy northerly winds will develop early
Thursday morning and continue into the early evening hours.
Temperatures will be noticeably warmer on Thursday.

High pressure will strengthen over the area on Friday with
continued warming of temperatures for the region.

&&


.EXTENDED DISCUSSION (Saturday THROUGH Tuesday)

High pressure will remain in control for the weekend into early next week.
This will bring dry weather, mostly clear skies, and warming
temperatures. A period of breezy northerly flow is likely over the
weekend as well. High temperatures will near the 90 degree mark in
the Valley by Sunday with widespread 90s (10 to 15 degrees above
normal) possible by Monday.

CEO

&&

.AVIATION...

VFR conditions next 24 hours. Light winds generally under 10 kts
overnight into early Wednesday for TAF sites. Light rain/snow will
begin to impact interior NorCal overnight thru Wednesday with a
slight chance of thunderstorms Wed afternoon/evening. Winds will
also become a bit breezy in the afternoon/early evening hours
with gusts 15-20 mph, especially near any thunderstorm
development.


&&

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

$$





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