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000
FXUS66 KSTO 281752
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
952 AM PST Fri Nov 28 2014

.Synopsis...
Confidence inreasing in both a weekend system and Tuesday-
Wendnesday storm system for some wet weather! The Saturday/Sunday
system may bring travel challenges above 6000 feet with 6 to 12
inches of snow expected. The next system on Tuesday/Wednesday
looks wetter and warmer with higher snow levels but more valley
rain.

&&

.Discussion...(Tonight through Monday)
Dense fog in the delta and along the west side of the Southern
Sacramento and Northern San Joaquin Valleys this morning.
Visibilities a quarter of a mile or less were reported in Fairfield,
Vacaville, Davis, Sacramento, and Stockton this morning. Visibilities
should be improving around 10 am. Temperatures will be cooler this
afternoon with highs in the mid 50s to mid 60s in the Valley and
40s to mid 50s in the mountains which is several degrees cooler
than yesterday. In the northern portion of the area ceilings are
lowering as rain is approaching. Rain has started along the
Northwest California coast this morning and will move inland to
around Redding ans surrounding by around noon then gradually shift
southeast to around the I-80 corridor this evening and into the
Northern San Joaquin Valley by early Saturday morning. Showers
will continue with some locations seeing breaks in the
precipitation Saturday afternoon and evening. Another wave moves
into the area Sunday bringing another round of precipitation.
Temperatures will continue to cool this weekend with highs in the
50s in the Valley and 30s to mid 40s in the mountains. Snow
levels will be around 5000-6000 ft in the Sierra and 4000-5000
over Shasta County this weekend. 6 to 12 inches of snow is
possible above 7000 ft this weekend which may bring some travel
delays over the Sierra and near Mt. Lassen. Precipitation amounts
through Sunday are expected to be around a half an inch to an inch
in the Valley and one to 2 inches for the foothills and lower
mountains. Although locally higher amounts are
possible...especially in the Feather River Basin. Monday may see a
break in the preciptiation especially south of I-80 corridor. The
next system starts moving into the North Monday afternoon and down
into the Sacramento area Tuesday morning.

.Extended Discussion (Tuesday through Friday)

Confidence coming together again for a nice wet system to move
across the area Tuesday into Wednesday. System is pretty warm with
snow levels above 6000 feet most of the time. ECMWF continues to
be wetter than the GFS and parallel GFS is wetter than the lower
res GFS. Total rain amounts range from around an inch with GFS in
the valley to several inches with ECMWF. Surely higher terrain
will get several inches to with up to 5 inches possible looking at
ECMWF which is in line with original thoughts with the
system...just a slower arrival. Rasch

&&

.Aviation...

Areas of IFR/LIFR fog will persist through about 18z today across
much of the Sacramento and northern San Joaquin Valleys. Pacific
storm system will begin to move through the area later today,
bringing rain to KRDD-KRBL by 18-20z and down to Sacramento TAF
sites after 03z Saturday. VFR/MVFR conditions initially in rain
will deteriorate to MVFR/IFR Friday night. Expect snow levels to
be around 6000 ft, with IFR/LIFR conditions over the mountains.

South winds up to 12 kt will be possible this afternoon and
tonight in advance of the front. Over the mountains, SW wind gusts
up to 45 kt possible today.

Dang


&&

.STO Watches/Warnings/Advisories...
winter weather advisory from midnight tonight to 7 pm pst sunday
above 6000 feet in the west slope northern sierra nevada...
western plumas county/lassen park.

dense fog advisory until 10 am pst this morning carquinez strait
and delta...central sacramento valley...northern san joaquin
valley...southern sacramento valley.

&&

$$








000
FXUS66 KSTO 281752
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
952 AM PST Fri Nov 28 2014

.Synopsis...
Confidence inreasing in both a weekend system and Tuesday-
Wendnesday storm system for some wet weather! The Saturday/Sunday
system may bring travel challenges above 6000 feet with 6 to 12
inches of snow expected. The next system on Tuesday/Wednesday
looks wetter and warmer with higher snow levels but more valley
rain.

&&

.Discussion...(Tonight through Monday)
Dense fog in the delta and along the west side of the Southern
Sacramento and Northern San Joaquin Valleys this morning.
Visibilities a quarter of a mile or less were reported in Fairfield,
Vacaville, Davis, Sacramento, and Stockton this morning. Visibilities
should be improving around 10 am. Temperatures will be cooler this
afternoon with highs in the mid 50s to mid 60s in the Valley and
40s to mid 50s in the mountains which is several degrees cooler
than yesterday. In the northern portion of the area ceilings are
lowering as rain is approaching. Rain has started along the
Northwest California coast this morning and will move inland to
around Redding ans surrounding by around noon then gradually shift
southeast to around the I-80 corridor this evening and into the
Northern San Joaquin Valley by early Saturday morning. Showers
will continue with some locations seeing breaks in the
precipitation Saturday afternoon and evening. Another wave moves
into the area Sunday bringing another round of precipitation.
Temperatures will continue to cool this weekend with highs in the
50s in the Valley and 30s to mid 40s in the mountains. Snow
levels will be around 5000-6000 ft in the Sierra and 4000-5000
over Shasta County this weekend. 6 to 12 inches of snow is
possible above 7000 ft this weekend which may bring some travel
delays over the Sierra and near Mt. Lassen. Precipitation amounts
through Sunday are expected to be around a half an inch to an inch
in the Valley and one to 2 inches for the foothills and lower
mountains. Although locally higher amounts are
possible...especially in the Feather River Basin. Monday may see a
break in the preciptiation especially south of I-80 corridor. The
next system starts moving into the North Monday afternoon and down
into the Sacramento area Tuesday morning.

.Extended Discussion (Tuesday through Friday)

Confidence coming together again for a nice wet system to move
across the area Tuesday into Wednesday. System is pretty warm with
snow levels above 6000 feet most of the time. ECMWF continues to
be wetter than the GFS and parallel GFS is wetter than the lower
res GFS. Total rain amounts range from around an inch with GFS in
the valley to several inches with ECMWF. Surely higher terrain
will get several inches to with up to 5 inches possible looking at
ECMWF which is in line with original thoughts with the
system...just a slower arrival. Rasch

&&

.Aviation...

Areas of IFR/LIFR fog will persist through about 18z today across
much of the Sacramento and northern San Joaquin Valleys. Pacific
storm system will begin to move through the area later today,
bringing rain to KRDD-KRBL by 18-20z and down to Sacramento TAF
sites after 03z Saturday. VFR/MVFR conditions initially in rain
will deteriorate to MVFR/IFR Friday night. Expect snow levels to
be around 6000 ft, with IFR/LIFR conditions over the mountains.

South winds up to 12 kt will be possible this afternoon and
tonight in advance of the front. Over the mountains, SW wind gusts
up to 45 kt possible today.

Dang


&&

.STO Watches/Warnings/Advisories...
winter weather advisory from midnight tonight to 7 pm pst sunday
above 6000 feet in the west slope northern sierra nevada...
western plumas county/lassen park.

dense fog advisory until 10 am pst this morning carquinez strait
and delta...central sacramento valley...northern san joaquin
valley...southern sacramento valley.

&&

$$









000
FXUS66 KSTO 281109
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
309 AM PST Fri Nov 28 2014

.Synopsis...
Confidence inreasing in both a weekend system and Tuesday-
Wendnesday storm system for some wet weather! The Saturday/Sunday
system may bring travel challenges above 6000 feet with 6 to 12
inches of snow expected. The next system on Tuesday/Wednesday
looks wetter and warmer with higher snow levels but more valley
rain.

&&

.Discussion...(Tonight through Monday)
Good agreement that wet weather will move into the area later
today through Sunday. This system will come in 2 waves with the
first line of rain pushing from north to south across the valley
starting late this afternoon in the north then south into the
Sacramento area late in the evening to around midnight. Snow will
then start around 6000 feet along with I-80 and I-5. This band has
consistently been forecast to linger a bit through mid morning on
Saturday then with off and on showers in higher terrain through
the day. There may be a little let up in activity overnight
Saturday night then pick back up Sunday as another wave pushes
through again. Snowlevels look to be a bit lower getting closer to
5000 feet but looks like accumulations will mostly remain above
6000 feet. Combining these 2 weather systems will put snow totals
in the 6 to 12 inch mark above 6000 feet...with probably some
higher amounts at some of the ski resorts. We will issue a winter
weather adivory starting at midnight Saturday through Sunday
evening. Rain looks to be heaviest in the southern Valley with a
good chance of mainy areas getting at least a half inch up to 1
inch.


.Extended Discussion (Tuesday through Friday)

Confidence coming together again for a nice wet system to move
across the area Tuesday into Wednesday. System is pretty warm with
snow levels above 6000 feet most of the time. ECMWF continues to
be wetter than the GFS and parallel GFS is wetter than the lower
res GFS. Total rain amounts range from around an inch with GFS in
the valley to several inches with ECMWF. Surely higher terrain
will get several inches to with up to 5 inches possible looking at
ECMWF which is in line with original thoughts with the
system...just a slower arrival. Rasch

&&

.Aviation...

Areas of IFR/LIFR fog will persist through about 18z today across
much of the Sacramento and northern San Joaquin Valleys. Pacific
storm system will begin to move through the area later today,
bringing rain to KRDD-KRBL by 18-20z and down to Sacramento TAF
sites after 03z Saturday. VFR/MVFR conditions initially in rain
will deteriorate to MVFR/IFR Friday night. Expect snow levels to
be around 6000 ft, with IFR/LIFR conditions over the mountains.

South winds up to 12 kt will be possible this afternoon and
tonight in advance of the front. Over the mountains, SW wind gusts
up to 45 kt possible today.

Dang


&&

.STO Watches/Warnings/Advisories...
winter weather advisory from midnight tonight to 7 pm pst sunday
above 6000 feet in the west slope northern sierra nevada...
western plumas county/lassen park.

&&

$$









000
FXUS66 KSTO 280525
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
925 PM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday and weekend.
Slick roads and snow above 6000 feet may cause travel delays.
Unfortunately a lot of uncertainty remains with next storm system
arriving sometime in the Monday through Thursday time frame, periods
of wet weather are possible next week.

&&

.Discussion...(Tonight through Sunday)
Tonight temperatures are running cooler and we dont have the high
clouds that we had last night. Some fog is starting to set up in
places from the Central Sacramento Valley southward. Areas of fog
looks likely to form in the overnight hours and could become dense
in some places...especially near the central part of the valley.

On Friday Some precipitation will be possible over the far
northwestern part of the state in the morning and may spread and
start to precipitate along the coastal range from around Lake
County northward and over northern half of the Sacramento valley.
There continues to be some timing differences but models do agree
on bringing precipitation to the coastal range and far northern
part of the interior. There is agreement on a jet moving over the
far north so would not be surprised to see some rain start early
during the day on Friday for the Northern Sacramento Valley.

Snow levels will be high for the onset of precipitation through
Friday evening but may lower below major pass trans-sierra levels
late Friday night to impact travel with several inches of snow
through Saturday. For Sacramento area and south the models are pointing
towards the start of rain from the evening hours to late at night
or early Saturday morning for the far southern sections of the CWA
in the Northern San Joaquin Valley. What is interesting is that
the Models are in agreement on bringing moderate rainfall to the
southern half of the Sacramento valley late Friday and Saturday
morning as the jet will be aloft over that area during that time
period.

Some colder air will move over the region Saturday night with
scattered showers likely lingering...mostly in the mountains.
Another weaker wave will move through on Sunday and looks to
impact the southern CWA more than the north as far as
precipitation amounts are concerned. This may bring a half foot of
snow below pass levels with slightly higher amounts over the crest.


.Extended Discussion (Monday through Thursday)

Models showing brief ridge building over NorCal Monday...have
lowered precip chances a few percent to show this trend. May need
to lower more in the future if models continue with this drier
solution. Euro and Gfs diverge on Tuesday/Wednesday with GFS
faster and wetter than Euro. Will keep a blend of the two going
with slight weighting to the wetter GFS. Roles are reversed
Thursday/Friday as Euro shows a wet system moving through
California with the GFS much drier. Needless to say much
uncertainty and low confidence exists in the extended forecast
especially with timing. Although...the pattern is shifting to a
much wetter one.


&&

.Aviation...

BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites Thanksgiving. Local MVFR/IFR conditions are possible around
Sacramento and Stockton aft 10z until 18z Friday. Lowering
ceilings and precipitation possible with areas of MVFR conditions by Friday
afternoon around KRDD and KRBL.

&&

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

$$








000
FXUS66 KSTO 280525
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
925 PM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday and weekend.
Slick roads and snow above 6000 feet may cause travel delays.
Unfortunately a lot of uncertainty remains with next storm system
arriving sometime in the Monday through Thursday time frame, periods
of wet weather are possible next week.

&&

.Discussion...(Tonight through Sunday)
Tonight temperatures are running cooler and we dont have the high
clouds that we had last night. Some fog is starting to set up in
places from the Central Sacramento Valley southward. Areas of fog
looks likely to form in the overnight hours and could become dense
in some places...especially near the central part of the valley.

On Friday Some precipitation will be possible over the far
northwestern part of the state in the morning and may spread and
start to precipitate along the coastal range from around Lake
County northward and over northern half of the Sacramento valley.
There continues to be some timing differences but models do agree
on bringing precipitation to the coastal range and far northern
part of the interior. There is agreement on a jet moving over the
far north so would not be surprised to see some rain start early
during the day on Friday for the Northern Sacramento Valley.

Snow levels will be high for the onset of precipitation through
Friday evening but may lower below major pass trans-sierra levels
late Friday night to impact travel with several inches of snow
through Saturday. For Sacramento area and south the models are pointing
towards the start of rain from the evening hours to late at night
or early Saturday morning for the far southern sections of the CWA
in the Northern San Joaquin Valley. What is interesting is that
the Models are in agreement on bringing moderate rainfall to the
southern half of the Sacramento valley late Friday and Saturday
morning as the jet will be aloft over that area during that time
period.

Some colder air will move over the region Saturday night with
scattered showers likely lingering...mostly in the mountains.
Another weaker wave will move through on Sunday and looks to
impact the southern CWA more than the north as far as
precipitation amounts are concerned. This may bring a half foot of
snow below pass levels with slightly higher amounts over the crest.


.Extended Discussion (Monday through Thursday)

Models showing brief ridge building over NorCal Monday...have
lowered precip chances a few percent to show this trend. May need
to lower more in the future if models continue with this drier
solution. Euro and Gfs diverge on Tuesday/Wednesday with GFS
faster and wetter than Euro. Will keep a blend of the two going
with slight weighting to the wetter GFS. Roles are reversed
Thursday/Friday as Euro shows a wet system moving through
California with the GFS much drier. Needless to say much
uncertainty and low confidence exists in the extended forecast
especially with timing. Although...the pattern is shifting to a
much wetter one.


&&

.Aviation...

BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites Thanksgiving. Local MVFR/IFR conditions are possible around
Sacramento and Stockton aft 10z until 18z Friday. Lowering
ceilings and precipitation possible with areas of MVFR conditions by Friday
afternoon around KRDD and KRBL.

&&

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

$$









000
FXUS66 KSTO 272245
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
245 PM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday and weekend.
Slick roads and snow above 6000 feet may cause travel delays.
Unfortunately a lot of uncertainty remains with next storm system
arriving sometime in the Monday through Thursday time frame, periods
of wet weather are possible next week.

&&

.Discussion...
Warm and dry Thanksgiving day today with some mid and high clouds
with a weak ridge over the area. Temperatures will peak in the
mid to upper 60s in the valley and upper 40s to low 60s in the
mountains this afternoon, which is about 6 to 12 degrees above
normal. Friday temperatures will cool with highs in the mid 50s
to mid 60s in the Valley and 40s to mid 50s in the mountains as an
upper level trough approaches the area. Saturday will be cooler
with highs in the low to mid 50s in the Valley and 30s to mid 40s
in the mountains.

Precipitation will start moving into the Coastal range and the
Northern Sacramento Valley Friday by noon and spread southeast to
around the I-80 corridor around midnight and in the Northern San Joaquin
Valley Saturday morning as the jet and 1.3 in Precipitatable water
plume sag south. A band of precipitation may be around the I-80
corridor Saturday morning bringing wet roads and snow over the
Sierra passes for possible travel delays. Precipitation is expected to
continue into Saturday evening with some weak upward motion and moisture.
Snow levels will be around 7500 ft (near pass level in the Sierra)
Friday evening and drop down to around 5500 ft Saturday morning.
Several inches of snow are possible above 6000 ft by Saturday
evening. Rainfall amounts are expected to be around a quarter to
three quarters in the Valley and generally around an inch to an
inch and a half in the mountains by Saturday evening.
Precipitation will probably continue at least at times on Sunday
but there is more uncertainty in the amounts. There is variability
in the models with the ECMWF with the strongest wave but all have
a little lift and some moisture for a chance of precipitation.


.Extended Discussion (Monday through Thursday)

Models showing brief ridge building over NorCal Monday...have
lowered precip chances a few percent to show this trend. May need
to lower more in the future if models continue with this drier
solution. Euro and Gfs diverge on Tuesday/Wednesday with GFS
faster and wetter than Euro. Will keep a blend of the two going
with slight weighting to the wetter GFS. Roles are reversed
Thursday/Friday as Euro shows a wet system moving through
California with the GFS much drier. Needless to say much
uncertainty and low confidence exists in the extended forecast
especially with timing. Although...the pattern is shifting to a
much wetter one.


&&

.Aviation...

BKN-OVC high clouds today with VFR/MVFR conditions with generally
light winds expected across TAF sites on Thanksgiving. Local
MVFR/IFR conditions are possible around Sacramento and Stockton
due to BR/FG aft 10z until 18z Friday. Lowering ceilings and
precipitation possible with areas of MVFR conditions by Friday
afternoon around KRDD and KRBL.

&&

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

$$








000
FXUS66 KSTO 272245
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
245 PM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday and weekend.
Slick roads and snow above 6000 feet may cause travel delays.
Unfortunately a lot of uncertainty remains with next storm system
arriving sometime in the Monday through Thursday time frame, periods
of wet weather are possible next week.

&&

.Discussion...
Warm and dry Thanksgiving day today with some mid and high clouds
with a weak ridge over the area. Temperatures will peak in the
mid to upper 60s in the valley and upper 40s to low 60s in the
mountains this afternoon, which is about 6 to 12 degrees above
normal. Friday temperatures will cool with highs in the mid 50s
to mid 60s in the Valley and 40s to mid 50s in the mountains as an
upper level trough approaches the area. Saturday will be cooler
with highs in the low to mid 50s in the Valley and 30s to mid 40s
in the mountains.

Precipitation will start moving into the Coastal range and the
Northern Sacramento Valley Friday by noon and spread southeast to
around the I-80 corridor around midnight and in the Northern San Joaquin
Valley Saturday morning as the jet and 1.3 in Precipitatable water
plume sag south. A band of precipitation may be around the I-80
corridor Saturday morning bringing wet roads and snow over the
Sierra passes for possible travel delays. Precipitation is expected to
continue into Saturday evening with some weak upward motion and moisture.
Snow levels will be around 7500 ft (near pass level in the Sierra)
Friday evening and drop down to around 5500 ft Saturday morning.
Several inches of snow are possible above 6000 ft by Saturday
evening. Rainfall amounts are expected to be around a quarter to
three quarters in the Valley and generally around an inch to an
inch and a half in the mountains by Saturday evening.
Precipitation will probably continue at least at times on Sunday
but there is more uncertainty in the amounts. There is variability
in the models with the ECMWF with the strongest wave but all have
a little lift and some moisture for a chance of precipitation.


.Extended Discussion (Monday through Thursday)

Models showing brief ridge building over NorCal Monday...have
lowered precip chances a few percent to show this trend. May need
to lower more in the future if models continue with this drier
solution. Euro and Gfs diverge on Tuesday/Wednesday with GFS
faster and wetter than Euro. Will keep a blend of the two going
with slight weighting to the wetter GFS. Roles are reversed
Thursday/Friday as Euro shows a wet system moving through
California with the GFS much drier. Needless to say much
uncertainty and low confidence exists in the extended forecast
especially with timing. Although...the pattern is shifting to a
much wetter one.


&&

.Aviation...

BKN-OVC high clouds today with VFR/MVFR conditions with generally
light winds expected across TAF sites on Thanksgiving. Local
MVFR/IFR conditions are possible around Sacramento and Stockton
due to BR/FG aft 10z until 18z Friday. Lowering ceilings and
precipitation possible with areas of MVFR conditions by Friday
afternoon around KRDD and KRBL.

&&

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

$$









000
FXUS66 KSTO 271720
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
920 AM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday and weekend.
Slick roads and snow above 6000 feet (where from 6 to 12 inches of
snow is possible late Friday into Sunday morning) may cause travel delays.
Unfortunately a lot of uncertainty remains with second storm
system arriving sometime in the Monday through Wednesday time
frame.

&&

.Discussion...
Mostly sunny Thanksgiving day with some mid and high clouds
moving through the area under weak ridge. Temperatures will peak in
the mid to upper 60s in the valley and upper 40s to low 60s in the
mountains this afternoon, which is about 6 to 12 degrees above
normal. Friday temperatures will cool with highs in the upper 50s
to mid 60s in the Valley and 40s to mid 50s in the mountains as
an upper level trough approaches the area. Precipitation will
start moving into the Coastal range and the Northern Sacramento
Valley Friday by noon and spread southeast to around the I-80
corridor in the evening and in the Northern San Joaquin Valley
Saturday morning as the jet and 1.3 in Precipitatable water plume
sag south. Precipitation is expected to continue during the day
Saturday with some weak upward motion and moisture. Saturday will
be cooler with highs in the low to mid 50s in the Valley and 30s
to mid 40s in the mountains. Snow levels will be around 7500 ft
(near pass level in the Sierra) Friday evening and drop down to
around 5500 ft Saturday morning. Several inches of snow are
possible above 6000 ft by Saturday evening. Rainfall amounts are
expected to be around a quarter to three quarters in the Valley and
generally around an inch to an inch and a half in the mountains by
Saturday evening. Precipitation will probably continue at least at
times on Sunday but there is more uncertainty in the amounts.
There is variability in the models with the ECMWF with the
strongest wave but all have a little lift and some moisture for
periods of precipitation.


.Extended Discussion (Monday through Thursday)

As noted from day shift yesterday...confidence unfortunately
decreasing with next system originally thought to be stronger of
these 2 systems. This still may be the case as it seems likely
upper low will eventually shift into CA but timing of that system
to arrive continues to be troublesome. GFS is deeper and further
east with the upper low Monday afternoon and night bringing
moisture into northern valley with ECMWF also unsettled but with
different solution keeping upper low further west.

Tuesday and Tuesday night...GFS moves the upper low to the coast
and into central CA which would bring some nice moisture to the area
(with parallel even wetter again)...with ECMWF again further west
delaying the arrival of it until Wednesday and Wednesday night. At
this time seems best message is that we should get another round
of rain...but when is unsure at this time. Either scenario though
doesn`t look to be much of an impact. Rasch


&&

.Aviation...

BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites Thanksgiving. Local MVFR/IFR conditions are possible around
Sacramento and Stockton aft 10z until 18z Friday. Lowering
ceilings and precipitation possible with areas of MVFR conditions by Friday
afternoon around KRDD and KRBL.

&&

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

$$








000
FXUS66 KSTO 271720
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
920 AM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday and weekend.
Slick roads and snow above 6000 feet (where from 6 to 12 inches of
snow is possible late Friday into Sunday morning) may cause travel delays.
Unfortunately a lot of uncertainty remains with second storm
system arriving sometime in the Monday through Wednesday time
frame.

&&

.Discussion...
Mostly sunny Thanksgiving day with some mid and high clouds
moving through the area under weak ridge. Temperatures will peak in
the mid to upper 60s in the valley and upper 40s to low 60s in the
mountains this afternoon, which is about 6 to 12 degrees above
normal. Friday temperatures will cool with highs in the upper 50s
to mid 60s in the Valley and 40s to mid 50s in the mountains as
an upper level trough approaches the area. Precipitation will
start moving into the Coastal range and the Northern Sacramento
Valley Friday by noon and spread southeast to around the I-80
corridor in the evening and in the Northern San Joaquin Valley
Saturday morning as the jet and 1.3 in Precipitatable water plume
sag south. Precipitation is expected to continue during the day
Saturday with some weak upward motion and moisture. Saturday will
be cooler with highs in the low to mid 50s in the Valley and 30s
to mid 40s in the mountains. Snow levels will be around 7500 ft
(near pass level in the Sierra) Friday evening and drop down to
around 5500 ft Saturday morning. Several inches of snow are
possible above 6000 ft by Saturday evening. Rainfall amounts are
expected to be around a quarter to three quarters in the Valley and
generally around an inch to an inch and a half in the mountains by
Saturday evening. Precipitation will probably continue at least at
times on Sunday but there is more uncertainty in the amounts.
There is variability in the models with the ECMWF with the
strongest wave but all have a little lift and some moisture for
periods of precipitation.


.Extended Discussion (Monday through Thursday)

As noted from day shift yesterday...confidence unfortunately
decreasing with next system originally thought to be stronger of
these 2 systems. This still may be the case as it seems likely
upper low will eventually shift into CA but timing of that system
to arrive continues to be troublesome. GFS is deeper and further
east with the upper low Monday afternoon and night bringing
moisture into northern valley with ECMWF also unsettled but with
different solution keeping upper low further west.

Tuesday and Tuesday night...GFS moves the upper low to the coast
and into central CA which would bring some nice moisture to the area
(with parallel even wetter again)...with ECMWF again further west
delaying the arrival of it until Wednesday and Wednesday night. At
this time seems best message is that we should get another round
of rain...but when is unsure at this time. Either scenario though
doesn`t look to be much of an impact. Rasch


&&

.Aviation...

BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites Thanksgiving. Local MVFR/IFR conditions are possible around
Sacramento and Stockton aft 10z until 18z Friday. Lowering
ceilings and precipitation possible with areas of MVFR conditions by Friday
afternoon around KRDD and KRBL.

&&

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

$$









000
FXUS66 KSTO 271134
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
334 AM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday night and
Saturday. Impacts with this first system not looking too bad but
should be limited to elevations above 6000 feet where from 6 to 12
inches of snow is possible late Friday into Sunday morning.
Unfortunately a lot of uncertainty remains with second storm
system arriving sometime in the Monday through Wednesday time
frame.

&&

.Discussion...(Today through Sunday Night) First weather system will
move into northern portions of the Valley Friday late afternoon
then push southward to Sacramento area early morning
Saturday..then linger around with some weak upward motion and
moisture through Saturday night. Parallel GFS continues to be
wetter with this system compared to operational GFS. SREF mean and
NAM also coming in wetter than operational GFS. With this in mind
tweaked up QPF values only slightly across the area during this
time. Snow levels will be tricky Saturday but should start around
5,000 feet and rise to around 6,000 feet than back down to around
5,000 feet by Sunday morning. Amounts enough to cause some impacts
but will likely be limited to elevations above 6,000 feet. Amounts
look to be low enough to continue to hold off on any highlights.

Sunday through Sunday night is another tricky period. GFS swings more
moisture and energy up into are for another round of precipitation.
Have kept pops pretty much the same in the 60 and greater area.
Snow levels should remain fairly high at or above 6,000 feet for
again minimal amounts and impacts. ECMWF at this time has more
ridging in the area but keeps some moisture and lift to produce
precipitation so overall looks like a cloudy and wet at times day.

.Extended Discussion (Monday through Thursday)

As noted from day shift yesterday...confidence unfortunately
decreasing with next system originally thought to be stronger of
these 2 systems. This still may be the case as it seems likely
upper low will eventually shift into CA but timing of that system
to arrive continues to be troublesome. GFS is more is deeper and
further east with the upper low Monday afternoon and night brining
miosture into northern valley with ECMWF also unsettled but with
different solution keeping upper low further west.

Tuesday and Tuesday night...GFS moves the upper low to the coast
and into central CA which would bring some nice moisture to the area
(with parallel even wetter again)...with ECMWF again further west
delaying the arrival of it until Wednesday and Wednesday night. At
this time seems best message is that we should get another round
of rain...but when is unsure at this time. Either scenario though
doesn`t look to be much of an impact. Rasch


&&

.Aviation...

BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites.

Dang


&&

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

$$








000
FXUS66 KSTO 271134
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
334 AM PST Thu Nov 27 2014

.Synopsis...
Mild Thanksgiving will give way to a wet Friday night and
Saturday. Impacts with this first system not looking too bad but
should be limited to elevations above 6000 feet where from 6 to 12
inches of snow is possible late Friday into Sunday morning.
Unfortunately a lot of uncertainty remains with second storm
system arriving sometime in the Monday through Wednesday time
frame.

&&

.Discussion...(Today through Sunday Night) First weather system will
move into northern portions of the Valley Friday late afternoon
then push southward to Sacramento area early morning
Saturday..then linger around with some weak upward motion and
moisture through Saturday night. Parallel GFS continues to be
wetter with this system compared to operational GFS. SREF mean and
NAM also coming in wetter than operational GFS. With this in mind
tweaked up QPF values only slightly across the area during this
time. Snow levels will be tricky Saturday but should start around
5,000 feet and rise to around 6,000 feet than back down to around
5,000 feet by Sunday morning. Amounts enough to cause some impacts
but will likely be limited to elevations above 6,000 feet. Amounts
look to be low enough to continue to hold off on any highlights.

Sunday through Sunday night is another tricky period. GFS swings more
moisture and energy up into are for another round of precipitation.
Have kept pops pretty much the same in the 60 and greater area.
Snow levels should remain fairly high at or above 6,000 feet for
again minimal amounts and impacts. ECMWF at this time has more
ridging in the area but keeps some moisture and lift to produce
precipitation so overall looks like a cloudy and wet at times day.

.Extended Discussion (Monday through Thursday)

As noted from day shift yesterday...confidence unfortunately
decreasing with next system originally thought to be stronger of
these 2 systems. This still may be the case as it seems likely
upper low will eventually shift into CA but timing of that system
to arrive continues to be troublesome. GFS is more is deeper and
further east with the upper low Monday afternoon and night brining
miosture into northern valley with ECMWF also unsettled but with
different solution keeping upper low further west.

Tuesday and Tuesday night...GFS moves the upper low to the coast
and into central CA which would bring some nice moisture to the area
(with parallel even wetter again)...with ECMWF again further west
delaying the arrival of it until Wednesday and Wednesday night. At
this time seems best message is that we should get another round
of rain...but when is unsure at this time. Either scenario though
doesn`t look to be much of an impact. Rasch


&&

.Aviation...

BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites.

Dang


&&

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

$$









000
FXUS66 KSTO 270514
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
914 PM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...(Tonight through Saturday)
Tonight and Thursday morning the dew points are coming up a
little but there should be a lot of high clouds that could help to
prevent a lot of fog from forming. Patchy fog still looks
possible during the late night and early morning hours. For
Thanksgiving the high pressure ridge will begin to break down and
shift eastward.

On Friday Some precipitation will be possible over the far
northwestern part of the state in the morning and may spread and
start to precipitate along the coastal range from around Lake
County northward and over northern half of the Sacramento valley.
There continues to be some timing differences but models do agree
on bringing precipitation to the coastal range and far northern
part of the interior. There is agreement on a jet moving over the
far north so would not be surprised to see some rain start early
during the day on Friday for the Northern Sacramento Valley. Snow
levels will be high for the onset of precipitation through Friday
daytime but may lower below major pass trans-sierra levels Friday
night to impact travel with snow. For Sacramento area and south
the models are pointing towards the start of rain from the evening
hours to late at night or early Saturday morning for the far
southern sections of the CWA.

Saturday will see the rain and higher elevation snow continuing
but below major trans-sierra pass levels. Major precipitation
discrepancies exist between the models so snowfall could range
from a little more than several inches to a foot or more near the
major trans-sierra pass levels. Stay tuned for updates and be
prepared to carry chains if traveling in the high country this
weekend.

.Extended Discussion (Sunday through Wednesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. The RMOP and the GFS
dprog/dt show a retrogression of the closed low that was to some
extent forecast by earlier runs of the ECMWF. The retrogression of
the upper low has resulted in slower Ewd movement and timing of the
precip for Norcal. Instead of the heaviest QPF expected from Sun
nite into Mon...or near the end of the holiday weekend during the
mass return/exodus of the public...the heaviest QPFs may not occur
until late Mon and/or Tue. This also follows the forecast of the
best period of Water Vapor (WV) transport into Norcal. Thus...the
impacts from the upper low may occur after the holiday period. (This
does not refer to the impacts from the previous (and relatively
weaker) waves bringing precip to our CWA Fri-Sun.)

A high probability of an inch or more of precip is forecast for the
Shasta Co area...and Siernev for the Sat...Sun...Mon periods...with
the highest probabilities in the latter two periods...and a 95%
probability of 2+ inches through Tue. The WPC 7 day QPF indicates
about 7-9 inches over the Siernev...mainly 1-3 inches for the valley
with the highest amounts in the Nrn Sac Vly tapering Swd. These
numbers correlate to a likely 95th probability of precip for the
valley and at least "chance" probability for the higher elevations.
Certainly a "dent" can be made in our precip deficit should this
materialize.

Due to the retrogression/slower timing of the models...Norcal will
be in the WAA zone ahead of the upper low throughout the weekend
with moderately high snow levels. There is a high degree of
uncertainty in the timing and amount of QPF Tue/Wed due to the
slower timing of the ECMWF and the seemingly too progressive GFS.
Thus...later in the EFP is subject to a myriad of changes.   JHM

&&

.Aviation...

BKN-OVC cirrus tonight and Thu. Patchy early morning fog/ST and
local IFR/LIFR conditions in the Central Vly and mtn
valleys/basins mainly from 10z-18z Thu.


&&

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

$$








000
FXUS66 KSTO 270514
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
914 PM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...(Tonight through Saturday)
Tonight and Thursday morning the dew points are coming up a
little but there should be a lot of high clouds that could help to
prevent a lot of fog from forming. Patchy fog still looks
possible during the late night and early morning hours. For
Thanksgiving the high pressure ridge will begin to break down and
shift eastward.

On Friday Some precipitation will be possible over the far
northwestern part of the state in the morning and may spread and
start to precipitate along the coastal range from around Lake
County northward and over northern half of the Sacramento valley.
There continues to be some timing differences but models do agree
on bringing precipitation to the coastal range and far northern
part of the interior. There is agreement on a jet moving over the
far north so would not be surprised to see some rain start early
during the day on Friday for the Northern Sacramento Valley. Snow
levels will be high for the onset of precipitation through Friday
daytime but may lower below major pass trans-sierra levels Friday
night to impact travel with snow. For Sacramento area and south
the models are pointing towards the start of rain from the evening
hours to late at night or early Saturday morning for the far
southern sections of the CWA.

Saturday will see the rain and higher elevation snow continuing
but below major trans-sierra pass levels. Major precipitation
discrepancies exist between the models so snowfall could range
from a little more than several inches to a foot or more near the
major trans-sierra pass levels. Stay tuned for updates and be
prepared to carry chains if traveling in the high country this
weekend.

.Extended Discussion (Sunday through Wednesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. The RMOP and the GFS
dprog/dt show a retrogression of the closed low that was to some
extent forecast by earlier runs of the ECMWF. The retrogression of
the upper low has resulted in slower Ewd movement and timing of the
precip for Norcal. Instead of the heaviest QPF expected from Sun
nite into Mon...or near the end of the holiday weekend during the
mass return/exodus of the public...the heaviest QPFs may not occur
until late Mon and/or Tue. This also follows the forecast of the
best period of Water Vapor (WV) transport into Norcal. Thus...the
impacts from the upper low may occur after the holiday period. (This
does not refer to the impacts from the previous (and relatively
weaker) waves bringing precip to our CWA Fri-Sun.)

A high probability of an inch or more of precip is forecast for the
Shasta Co area...and Siernev for the Sat...Sun...Mon periods...with
the highest probabilities in the latter two periods...and a 95%
probability of 2+ inches through Tue. The WPC 7 day QPF indicates
about 7-9 inches over the Siernev...mainly 1-3 inches for the valley
with the highest amounts in the Nrn Sac Vly tapering Swd. These
numbers correlate to a likely 95th probability of precip for the
valley and at least "chance" probability for the higher elevations.
Certainly a "dent" can be made in our precip deficit should this
materialize.

Due to the retrogression/slower timing of the models...Norcal will
be in the WAA zone ahead of the upper low throughout the weekend
with moderately high snow levels. There is a high degree of
uncertainty in the timing and amount of QPF Tue/Wed due to the
slower timing of the ECMWF and the seemingly too progressive GFS.
Thus...later in the EFP is subject to a myriad of changes.   JHM

&&

.Aviation...

BKN-OVC cirrus tonight and Thu. Patchy early morning fog/ST and
local IFR/LIFR conditions in the Central Vly and mtn
valleys/basins mainly from 10z-18z Thu.


&&

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

$$









000
FXUS66 KSTO 262318
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
318 PM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Ridge of high pressure over the area today bringing above normal
temperatures and mostly sunny skies. Some high clouds ahead of the
approaching storm system are moving through the area. Temperatures
this afternoon should peak in the mid to upper 60s in the Central
Valley and foothills and 50s and 60s in the mountains which is
around 7 to 15 degrees above normal for this time of year. Mostly
clear skies and remnant low level moisture will bring a return of
the patchy fog to the valleys again Thursday morning. Ridge
weakens Thursday as trough approaches the area but will still be warm
with mostly sunny skies. Temperatures for Thanksgiving afternoon
are expected to be in the mid to upper 60s in the Valley and mid
40s to low 60s in the mountains.

The weather will turn cooler and wetter Friday into next week as
several storm systems move through the area. Temperatures start to
cool on Friday as the upper level trough nears the coast. High temperatures
in the upper 50s to mid 60s in the Valley and mid 40s to 50s in
the mountains on Friday and drop in the 50s in the Valley and 30s
and 40s in the mountains on Saturday. Clouds will increase on
Friday with precipitation expected to start moving into the
Coastal range by Friday afternoon. Precipitation will spread
southeast across the area to around the I-80 corridor Friday
evening and farther south into the Northern San Joaquin Valley
Saturday morning. Snow levels are expected to be around 7500 ft
Friday and lower to around 6000 feet Saturday. This will bring
snow down to the Sierra passes this weekend possibly causing
travel delays. A few inches of snow are possible in the Sierra
with around 18 inches possible for the top of Mt. Lassen.
Rainfall totals for Friday and Saturday are expected to be around
a quarter to half an inch in the Central Valley and . Generally
around 0.75 to 1.5 inches for the mountains...mainly north of
I-80. Southerly winds will bring breezy conditions on Saturday also.

.Extended Discussion (Sunday through Wednesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. The RMOP and the GFS
dprog/dt show a retrogression of the closed low that was to some
extent forecast by earlier runs of the ECMWF. The retrogression of
the upper low has resulted in slower Ewd movement and timing of the
precip for Norcal. Instead of the heaviest QPF expected from Sun
nite into Mon...or near the end of the holiday weekend during the
mass return/exodus of the public...the heaviest QPFs may not occur
until late Mon and/or Tue. This also follows the forecast of the
best period of Water Vapor (WV) transport into Norcal. Thus...the
impacts from the upper low may occur after the holiday period. (This
does not refer to the impacts from the previous (and relatively
weaker) waves bringing precip to our CWA Fri-Sun.)

A high probability of an inch or more of precip is forecast for the
Shasta Co area...and Siernev for the Sat...Sun...Mon periods...with
the highest probabilities in the latter two periods...and a 95%
probability of 2+ inches through Tue. The WPC 7 day QPF indicates
about 7-9 inches over the Siernev...mainly 1-3 inches for the valley
with the highest amounts in the Nrn Sac Vly tapering Swd. These
numbers correlate to a likely 95th probability of precip for the
valley and at least "chance" probability for the higher elevations.
Certainly a "dent" can be made in our precip deficit should this
materialize.

Due to the retrogression/slower timing of the models...Norcal will
be in the WAA zone ahead of the upper low throughout the weekend
with moderately high snow levels. There is a high degree of
uncertainty in the timing and amount of QPF Tue/Wed due to the
slower timing of the ECMWF and the seemingly too progressive GFS.
Thus...later in the EFP is subject to a myriad of changes.   JHM

&&

.Aviation...

Becoming BKN-OVC cirrus tonight and Thu. Patchy early morning
fog/ST and local IFR/LIFR conditions in the Central Vly and mtn
valleys/basins mainly from 10z-18z Thu.


&&

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

$$








000
FXUS66 KSTO 262318
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
318 PM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Ridge of high pressure over the area today bringing above normal
temperatures and mostly sunny skies. Some high clouds ahead of the
approaching storm system are moving through the area. Temperatures
this afternoon should peak in the mid to upper 60s in the Central
Valley and foothills and 50s and 60s in the mountains which is
around 7 to 15 degrees above normal for this time of year. Mostly
clear skies and remnant low level moisture will bring a return of
the patchy fog to the valleys again Thursday morning. Ridge
weakens Thursday as trough approaches the area but will still be warm
with mostly sunny skies. Temperatures for Thanksgiving afternoon
are expected to be in the mid to upper 60s in the Valley and mid
40s to low 60s in the mountains.

The weather will turn cooler and wetter Friday into next week as
several storm systems move through the area. Temperatures start to
cool on Friday as the upper level trough nears the coast. High temperatures
in the upper 50s to mid 60s in the Valley and mid 40s to 50s in
the mountains on Friday and drop in the 50s in the Valley and 30s
and 40s in the mountains on Saturday. Clouds will increase on
Friday with precipitation expected to start moving into the
Coastal range by Friday afternoon. Precipitation will spread
southeast across the area to around the I-80 corridor Friday
evening and farther south into the Northern San Joaquin Valley
Saturday morning. Snow levels are expected to be around 7500 ft
Friday and lower to around 6000 feet Saturday. This will bring
snow down to the Sierra passes this weekend possibly causing
travel delays. A few inches of snow are possible in the Sierra
with around 18 inches possible for the top of Mt. Lassen.
Rainfall totals for Friday and Saturday are expected to be around
a quarter to half an inch in the Central Valley and . Generally
around 0.75 to 1.5 inches for the mountains...mainly north of
I-80. Southerly winds will bring breezy conditions on Saturday also.

.Extended Discussion (Sunday through Wednesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. The RMOP and the GFS
dprog/dt show a retrogression of the closed low that was to some
extent forecast by earlier runs of the ECMWF. The retrogression of
the upper low has resulted in slower Ewd movement and timing of the
precip for Norcal. Instead of the heaviest QPF expected from Sun
nite into Mon...or near the end of the holiday weekend during the
mass return/exodus of the public...the heaviest QPFs may not occur
until late Mon and/or Tue. This also follows the forecast of the
best period of Water Vapor (WV) transport into Norcal. Thus...the
impacts from the upper low may occur after the holiday period. (This
does not refer to the impacts from the previous (and relatively
weaker) waves bringing precip to our CWA Fri-Sun.)

A high probability of an inch or more of precip is forecast for the
Shasta Co area...and Siernev for the Sat...Sun...Mon periods...with
the highest probabilities in the latter two periods...and a 95%
probability of 2+ inches through Tue. The WPC 7 day QPF indicates
about 7-9 inches over the Siernev...mainly 1-3 inches for the valley
with the highest amounts in the Nrn Sac Vly tapering Swd. These
numbers correlate to a likely 95th probability of precip for the
valley and at least "chance" probability for the higher elevations.
Certainly a "dent" can be made in our precip deficit should this
materialize.

Due to the retrogression/slower timing of the models...Norcal will
be in the WAA zone ahead of the upper low throughout the weekend
with moderately high snow levels. There is a high degree of
uncertainty in the timing and amount of QPF Tue/Wed due to the
slower timing of the ECMWF and the seemingly too progressive GFS.
Thus...later in the EFP is subject to a myriad of changes.   JHM

&&

.Aviation...

Becoming BKN-OVC cirrus tonight and Thu. Patchy early morning
fog/ST and local IFR/LIFR conditions in the Central Vly and mtn
valleys/basins mainly from 10z-18z Thu.


&&

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

$$









000
FXUS66 KSTO 261752
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
952 AM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Patchy fog in the valleys this morning but starting to dissipate
and visibilities improving around 9 am. Mostly sunny skies (with
some mid and high clouds) and above normal temperatures today with
another day under ridge of high pressure. Temperatures this
afternoon are expected to peak in the mid to upper 60s in the
Central Valley and foothills and 50s to mid 60s in the mountains.
Increasing clouds for Thanksgiving as a storm system approaches
but temperatures will remain above normal. Patchy fog in the
valleys will also return for Thanksgiving morning.

The weather will turn cooler and wetter Friday into next week as
several storm systems move through the area. Temperatures start to
cool on Friday as the ridge shifts east, with temperatures in the upper
50s to mid 60s in the Valley and mid 40s to 50s in the mountains.
Precipitation is expected to start moving into the Coastal range
Friday morning and gradually spread southeast across the area to
around the I-80 corridor Friday evening and farther south into the
Northern San Joaquin Valley Saturday morning. Temperatures will
cool to near normal on Saturday with highs in the mid 50s to low
60s in the Valley and mid 30s to 40s in the mountains. Snow levels
are expected to be around 7500 ft Friday and lower to around 6000
feet Saturday. A few inches of snow are possible in the Sierra
with around a foot possible for the top of Mt. Lassen. Rainfall
totals for Friday and Saturday are expected to be around 1.5
inches around Redding to around 0.75 inches around Sacramento and
around a third of an inch in the Northern San Joaquin Valley.
Generally around 1 to 2.5 inches for the mountains...mainly north
of I-80.
&&

.Extended Discussion (Sunday through Wednesday)

Development of a deep, closed upper level low off the CA coast
late this holiday weekend threatens to bring significant
rain/mountain snow to interior NorCal into early next week. The
NCEP GEFS shows a 70% probability of at least 1 inch of mountain
precipitation, and a 40% probability of at least 2 inches. The
GFS/EC/GEM all show warm frontal type precip Sunday with the main
low still west of 130W.

Mid range models have been showing several inches of rain
from Saturday through Monday; however, the amounts/timing could
be in jeopardy as the models have shown signs of diverging. The
GFS and GEM show the low slowly filling and progressing inside
130W on Monday with decent amounts of precipitation. On the other
hand, the EC cuts off the low west of 130W with little movement
eastward until Tuesday. While a multi-day precip event for NorCal
exists, model differences in timing could result in greater,
lesser, or delayed results/impacts. In spite of the EC diverging,
we have kept precipitation amount relatively constant. For now,
the heaviest precip forecast is still expected to occur from
Sunday night through Monday. Significant snow may accompany this
wet period. Light snow accumulation may occur down to 4500-5000 ft
and 5-10 inches of snow may accumulate above 6000 ft with 12-36
inches above 7000 ft. The higher end amounts would likely occur
over Lassen Park and into western Plumas county.    JClapp

&&

.Aviation...

Early morning patch IFR/LIFR fog/stratus conditions in the
Central Valley and mtn valleys/basins. Dewpoints increased from
yesterday, so expect to see more fog. Most will be patchy and
relatively shallow.     JClapp

&&

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

$$









000
FXUS66 KSTO 261200
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
400 AM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Mainly clear skies across the interior of NorCal early this
morning as only a few high clouds are managing to spill through
the ridge. Early morning temperatures are pretty similar to
readings of 24 hours ago and range from the 20s in the colder
mountain valleys to the upper 30s to mid 40s in the Central Valley
with 50s in the thermal belts. Patchy valley fog will also be
possible through mid-morning.

Strong ridging will maintain dry and mild weather for the region
through Thanksgiving. We`ll begin to see more high clouds on
Thanksgiving as the ridge axis shifts east into the Great Basin.

Precipitation chances will gradually spread south on Friday (but
will likely remain north of I-80) as deeper moisture (TPW over an
inch) moves up from the southwest and warm advection increases.
Frontal system is forecast to push southward into the northern San
Joaquin Valley Saturday as the upper jet shifts south. The higher
elevations of the northern Sierra may begin to see a little
accumulating snow.

More significant potential impacts will hold off until late in the
weekend and early next week.

&&

.Extended Discussion (Sunday through Wednesday)...
Development of a deep, closed upper level low off the CA coast
late this holiday weekend threatens to bring significant
rain/mountain snow to interior NorCal into early next week. The
NCEP GEFS shows a 70% probability of at least 1 inch of mountain
precipitation, and a 40% probability of at least 2 inches. The
GFS/EC/GEM all show warm frontal type precip Sunday with the main
low still west of 130W.

Mid range models have been showing several inches of rain
from Saturday through Monday; however, the amounts/timing could
be in jeopardy as the models have shown signs of diverging. The
GFS and GEM show the low slowly filling and progressing inside
130W on Monday with decent amounts of precipitation. On the other
hand, the EC cuts off the low west of 130W with little movement
eastward until Tuesday. While a multi-day precip event for NorCal
exists, model differences in timing could result in greater,
lesser, or delayed results/impacts. In spite of the EC diverging,
we have kept precipitation amount relatively constant. For now,
the heaviest precip forecast is still expected to occur from
Sunday night through Monday. Significant snow may accompany this
wet period. Light snow accumulation may occur down to 4500-5000 ft
and 5-10 inches of snow may accumulate above 6000 ft with 12-36
inches above 7000 ft. The higher end amounts would likely occur
over Lassen Park and into western Plumas county. JClapp

&&

.Aviation...
Early morning patch IFR/LIFR fog/stratus conditions in the
Central Valley and mtn valleys/basins. Dewpoints increased from
yesterday, so expect to see more fog. Most will be patchy and
relatively shallow. JClapp

&&

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

&&

$$









000
FXUS66 KSTO 261200
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
400 AM PST Wed Nov 26 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Mainly clear skies across the interior of NorCal early this
morning as only a few high clouds are managing to spill through
the ridge. Early morning temperatures are pretty similar to
readings of 24 hours ago and range from the 20s in the colder
mountain valleys to the upper 30s to mid 40s in the Central Valley
with 50s in the thermal belts. Patchy valley fog will also be
possible through mid-morning.

Strong ridging will maintain dry and mild weather for the region
through Thanksgiving. We`ll begin to see more high clouds on
Thanksgiving as the ridge axis shifts east into the Great Basin.

Precipitation chances will gradually spread south on Friday (but
will likely remain north of I-80) as deeper moisture (TPW over an
inch) moves up from the southwest and warm advection increases.
Frontal system is forecast to push southward into the northern San
Joaquin Valley Saturday as the upper jet shifts south. The higher
elevations of the northern Sierra may begin to see a little
accumulating snow.

More significant potential impacts will hold off until late in the
weekend and early next week.

&&

.Extended Discussion (Sunday through Wednesday)...
Development of a deep, closed upper level low off the CA coast
late this holiday weekend threatens to bring significant
rain/mountain snow to interior NorCal into early next week. The
NCEP GEFS shows a 70% probability of at least 1 inch of mountain
precipitation, and a 40% probability of at least 2 inches. The
GFS/EC/GEM all show warm frontal type precip Sunday with the main
low still west of 130W.

Mid range models have been showing several inches of rain
from Saturday through Monday; however, the amounts/timing could
be in jeopardy as the models have shown signs of diverging. The
GFS and GEM show the low slowly filling and progressing inside
130W on Monday with decent amounts of precipitation. On the other
hand, the EC cuts off the low west of 130W with little movement
eastward until Tuesday. While a multi-day precip event for NorCal
exists, model differences in timing could result in greater,
lesser, or delayed results/impacts. In spite of the EC diverging,
we have kept precipitation amount relatively constant. For now,
the heaviest precip forecast is still expected to occur from
Sunday night through Monday. Significant snow may accompany this
wet period. Light snow accumulation may occur down to 4500-5000 ft
and 5-10 inches of snow may accumulate above 6000 ft with 12-36
inches above 7000 ft. The higher end amounts would likely occur
over Lassen Park and into western Plumas county. JClapp

&&

.Aviation...
Early morning patch IFR/LIFR fog/stratus conditions in the
Central Valley and mtn valleys/basins. Dewpoints increased from
yesterday, so expect to see more fog. Most will be patchy and
relatively shallow. JClapp

&&

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

&&

$$








000
FXUS66 KSTO 260506
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
906 PM PST Tue Nov 25 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
High pressure ridge will remain in place for Wednesday.
Temperatures will warm slightly for most locations over today.
Overnight dew points are up by several degrees so a few patches of
fog will be possible for the late night and early morning hours
over the Southern Sacramento and Northern San Joaquin Valley and
delta region.

For Wednesday night and Thursday morning the dew points should
come up a little but there should be a lot of high clouds that
could help to prevent a lot of fog from forming but patchy still
looks possible. For Thanksgiving the high pressure ridge will
begin to break down and shift eastward. Some precipitation will be
possible over the far northwestern part of the state.

On Friday there are timing differences but models do agree on
bringing precipitation to the coastal range and far northern part
of the interior. There is agreement on a jet moving over the far
north so would not be surprised to see some rain start early during
the day on Friday for the Northern Sacramento Valley. Snow levels
will be high for the onset of precipitation through Friday daytime
but may lower below major pass trans-sierra levels Friday night to
impact travel with snow. For Sacramento area and south the models
are pointing towards the start of rain from the evening hours to
late at night or early Saturday morning for the far southern
sections of the CWA.

&&

.Extended Discussion (Saturday through Tuesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. While there is a high
degree of confidence in a multi-day precip event for Norcal...model
differences in timing could result in greater or lesser impacts. For
now...the heaviest QPF is expected to occur from Sun nite into
Mon...or near the end of the holiday weekend during the mass
return/exodus of the public. A high probability (60-70% chance)
of an inch or more of precip is forecast for the Shasta Co
area and Siernev for the Sat...Sun...Mon periods...with the
highest probabilities in the latter two periods. Last nite`s GFS
shows a more substantial TPW plume to work with than the GEFS
ensemble and we are leaning wetter in the EFP due to the slower
timing and multi-day precip event.
Due to the slower timing of the models...Norcal will be in the WAA
zone ahead of the upper low early in the weekend and we have
adjusted the snow levels upwards to account for this timing. In the
later periods...there is more uncertainty in the timing and amount
of QPF into Tue due to the slower movement of the ECMWF positively-
tilted trof. The GFS may be too progressive with the trof and the
slower timing of the GEM/ECMWF for lingering precip into at least
Tue morning is preferred.    JHM

&&

.Aviation...

VFR SKC with light winds tonight thru Wed with the exception of
early morning fog/ST and local IFR/LIFR conditions in the Central
Vly and mtn valleys/basins.

&&

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

$$









000
FXUS66 KSTO 260506
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
906 PM PST Tue Nov 25 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
High pressure ridge will remain in place for Wednesday.
Temperatures will warm slightly for most locations over today.
Overnight dew points are up by several degrees so a few patches of
fog will be possible for the late night and early morning hours
over the Southern Sacramento and Northern San Joaquin Valley and
delta region.

For Wednesday night and Thursday morning the dew points should
come up a little but there should be a lot of high clouds that
could help to prevent a lot of fog from forming but patchy still
looks possible. For Thanksgiving the high pressure ridge will
begin to break down and shift eastward. Some precipitation will be
possible over the far northwestern part of the state.

On Friday there are timing differences but models do agree on
bringing precipitation to the coastal range and far northern part
of the interior. There is agreement on a jet moving over the far
north so would not be surprised to see some rain start early during
the day on Friday for the Northern Sacramento Valley. Snow levels
will be high for the onset of precipitation through Friday daytime
but may lower below major pass trans-sierra levels Friday night to
impact travel with snow. For Sacramento area and south the models
are pointing towards the start of rain from the evening hours to
late at night or early Saturday morning for the far southern
sections of the CWA.

&&

.Extended Discussion (Saturday through Tuesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. While there is a high
degree of confidence in a multi-day precip event for Norcal...model
differences in timing could result in greater or lesser impacts. For
now...the heaviest QPF is expected to occur from Sun nite into
Mon...or near the end of the holiday weekend during the mass
return/exodus of the public. A high probability (60-70% chance)
of an inch or more of precip is forecast for the Shasta Co
area and Siernev for the Sat...Sun...Mon periods...with the
highest probabilities in the latter two periods. Last nite`s GFS
shows a more substantial TPW plume to work with than the GEFS
ensemble and we are leaning wetter in the EFP due to the slower
timing and multi-day precip event.
Due to the slower timing of the models...Norcal will be in the WAA
zone ahead of the upper low early in the weekend and we have
adjusted the snow levels upwards to account for this timing. In the
later periods...there is more uncertainty in the timing and amount
of QPF into Tue due to the slower movement of the ECMWF positively-
tilted trof. The GFS may be too progressive with the trof and the
slower timing of the GEM/ECMWF for lingering precip into at least
Tue morning is preferred.    JHM

&&

.Aviation...

VFR SKC with light winds tonight thru Wed with the exception of
early morning fog/ST and local IFR/LIFR conditions in the Central
Vly and mtn valleys/basins.

&&

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

$$








000
FXUS66 KSTO 252341
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
341 PM PST Tue Nov 25 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Strengthening upper level ridging is going to bring continued mild
weather to the area through Thanksgiving. Afternoon temperatures
will peak well above normal levels on Wednesday, with slightly
cooler highs on Thursday as high clouds begin to spread in. There
could be some patchy morning fog/mist in the Valley and mountain
valleys Wednesday and possibly again early Thursday.

A weak wave will bring some precipitation gradually spreading
into the area from north to south Friday. Models have trended a
little slower with this system. The precipitation should be
mainly north of I80 during the day and should have limited impact
on travel. More substantial moisture arrives on Saturday, with
some accumulating snow beginning early Saturday, with more
significant amounts late Saturday through early Sunday. Snow
levels are projected to drop to around 6000-7000 feet on Saturday
and then down to around 6000 feet by early Sunday. Snow amounts
Saturday should generally be relatively light. More impactful snow
is possible Saturday night into early Sunday. Holiday travelers,
especially those going over Sierra passes, should closely monitor
the forecast as it evolves over the next several days. EK

&&

.Extended Discussion (Saturday through Tuesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. While there is a high
degree of confidence in a multi-day precip event for Norcal...model
differences in timing could result in greater or lesser impacts. For
now...the heaviest QPF is expected to occur from Sun nite into
Mon...or near the end of the holiday weekend during the mass
return/exodus of the public. A high probability of an inch or more
of precip is forecast for the Shasta Co area...and Siernev for the
Sat...Sun...Mon periods...with the highest probabilities in the
latter two periods.

Due to the slower timing of the models...Norcal will be in the WAA
zone ahead of the upper low early in the weekend and we have
adjusted the snow levels upwards to account for this timing. In the
later periods...there is more uncertainty in the timing and amount
of QPF into Tue due to the slower movement of the ECMWF positively-
tilted trof. The GFS may be too progressive with the trof and the
slower timing of the GEM/ECMWF for lingering precip into at least
Tue morning is preferred.    JHM

&&

.Aviation...

VFR SKC with light winds tonight thru Wed with the exception of
early morning fog/ST and local IFR/LIFR conditions in the Central
Vly and mtn valleys/basins.

&&

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

$$









000
FXUS66 KSTO 252341
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
341 PM PST Tue Nov 25 2014

.Synopsis...
Dry and mild weather is expected through Thanksgiving as high
pressure covers the region. Rain is expected to return to the
region by late Friday and continue into early next week. Snow
across the mountains is likely to cause travel difficulties for
the holiday weekend and into early next week.

&&

.Discussion...
Strengthening upper level ridging is going to bring continued mild
weather to the area through Thanksgiving. Afternoon temperatures
will peak well above normal levels on Wednesday, with slightly
cooler highs on Thursday as high clouds begin to spread in. There
could be some patchy morning fog/mist in the Valley and mountain
valleys Wednesday and possibly again early Thursday.

A weak wave will bring some precipitation gradually spreading
into the area from north to south Friday. Models have trended a
little slower with this system. The precipitation should be
mainly north of I80 during the day and should have limited impact
on travel. More substantial moisture arrives on Saturday, with
some accumulating snow beginning early Saturday, with more
significant amounts late Saturday through early Sunday. Snow
levels are projected to drop to around 6000-7000 feet on Saturday
and then down to around 6000 feet by early Sunday. Snow amounts
Saturday should generally be relatively light. More impactful snow
is possible Saturday night into early Sunday. Holiday travelers,
especially those going over Sierra passes, should closely monitor
the forecast as it evolves over the next several days. EK

&&

.Extended Discussion (Saturday through Tuesday)

Development of a deep...closed upper-level low off the CA coast
during the holiday weekend promises to bring significant rain/mtn
snow to interior Norcal into early next week. A strong probability/
measure of predictability is forecast by the NCEP 15 days 500 mbs
height ensemble for this scenario to unfold. While there is a high
degree of confidence in a multi-day precip event for Norcal...model
differences in timing could result in greater or lesser impacts. For
now...the heaviest QPF is expected to occur from Sun nite into
Mon...or near the end of the holiday weekend during the mass
return/exodus of the public. A high probability of an inch or more
of precip is forecast for the Shasta Co area...and Siernev for the
Sat...Sun...Mon periods...with the highest probabilities in the
latter two periods.

Due to the slower timing of the models...Norcal will be in the WAA
zone ahead of the upper low early in the weekend and we have
adjusted the snow levels upwards to account for this timing. In the
later periods...there is more uncertainty in the timing and amount
of QPF into Tue due to the slower movement of the ECMWF positively-
tilted trof. The GFS may be too progressive with the trof and the
slower timing of the GEM/ECMWF for lingering precip into at least
Tue morning is preferred.    JHM

&&

.Aviation...

VFR SKC with light winds tonight thru Wed with the exception of
early morning fog/ST and local IFR/LIFR conditions in the Central
Vly and mtn valleys/basins.

&&

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

$$








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