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000
FXUS66 KSTO 011649
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
849 AM PST Sun Feb 1 2015

.Synopsis...
Light precipitation possible in far northern portions late today
through Tuesday night. Above normal temperatures still expected
next week. Night and morning fog possible in the Central Valley
today into early next week. Increasing confidence in wet pattern
returning late in the week.

&&

.Short Term Discussion (Today through Wednesday)...
Patchy Dense Fog in the Northern San Joaquin and Delta area
and West of Sacramento this morning. Dense Fog reported at Davis,
Vacaville and Fairfield and Stockton with visibilities less than a
quarter of a mile at 8 am. Dense fog advisory out until 10 am this
morning. Visibilities should start increasing around 10 am as the
fog and low clouds dissipate. Patchy fog is expected to return to
areas around Sacramento, Delta and the Northern San Joaquin Valley
again the next few mornings.

High pressure weakens over the area with flattening ridge the next few
days bringing cooler temperatures (but still generally 5 to 10
degrees above normal) and possibly some precipitation to the
Northern portion of the Sacramento Valley and surrounding
mountains. The most cooling will be today with temperatures around
5 to 10 degrees cooler than yesterday due to high clouds and a
cooler air mass (850 mb temps drop around 3 degrees C). This will
bring afternoon temperatures down into the 60s in the Valley and
50s in the mountains which is still around 6 to 12 degrees above
normal for the beginning of February. Weak systems moving through
the fairly flat ridge will brush by the north bringing a chance of
precipitation this afternoon into Tuesday for the Northern
Sacramento Valley and surrounding mountains. Precipitation amounts
will be light with a quarter to half inch around Mt. Lassen and Shasta
County mountains, around 0.15 inches around Redding and less then
a tenth of an inch south of Redding in the Valley to around Chico.
Ridge builds up some on Wednesday ahead of a trough. The ridge
will bring a dry day and warmer temperatures up north with less
cloud cover. Patchy Valley fog is expected again in the morning.
The approaching trough may bring wet weather Thursday into the
weekend for Northern California.

.Extended Discussion (Thursday through Sunday)

No major changes in the models for the extended period continues
to lend confidence toward a return of wet weather for much of the
region later this week.

Ridge of high pressure still forecast to shift east into the
Rockies late this week as trough over the Gulf of Alaska edges a
bit closer. Models continue to forecast a period of very moist
southwesterly flow into NorCal late in the week and next weekend
(TPW plume in excess of 1.5 inches).

Heaviest QPF still forecast over northwest California with a shot
of decent precipitation likely extending south to around I-80
Friday into Saturday as strong upper jet noses onto the west coast
and IVT increases to well above normal.

&&

.Aviation...

VFR conditions across interior NorCal except for a band of dense
fog located along waterways. This is mainly impacting the Delta,
just west of KSMF and extending southward into the northern San
Joaquin Valley impacting KMOD with LIFR/IFR conditions. This is
dispersing by around 17-18Z, with lingering BR/HZ. Light
northerly winds this morning shifting to light southerly in the
afternoon. Disturbances passing to the north will bring increasing
mid and high clouds with shower chances limited to the northern
mountains.

&&

.STO Watches/Warnings/Advisories...
dense fog advisory until 10 am pst this morning carquinez strait
and delta...northern san joaquin valley...southern sacramento
valley.

&&

$$









000
FXUS66 KSTO 011649
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
849 AM PST Sun Feb 1 2015

.Synopsis...
Light precipitation possible in far northern portions late today
through Tuesday night. Above normal temperatures still expected
next week. Night and morning fog possible in the Central Valley
today into early next week. Increasing confidence in wet pattern
returning late in the week.

&&

.Short Term Discussion (Today through Wednesday)...
Patchy Dense Fog in the Northern San Joaquin and Delta area
and West of Sacramento this morning. Dense Fog reported at Davis,
Vacaville and Fairfield and Stockton with visibilities less than a
quarter of a mile at 8 am. Dense fog advisory out until 10 am this
morning. Visibilities should start increasing around 10 am as the
fog and low clouds dissipate. Patchy fog is expected to return to
areas around Sacramento, Delta and the Northern San Joaquin Valley
again the next few mornings.

High pressure weakens over the area with flattening ridge the next few
days bringing cooler temperatures (but still generally 5 to 10
degrees above normal) and possibly some precipitation to the
Northern portion of the Sacramento Valley and surrounding
mountains. The most cooling will be today with temperatures around
5 to 10 degrees cooler than yesterday due to high clouds and a
cooler air mass (850 mb temps drop around 3 degrees C). This will
bring afternoon temperatures down into the 60s in the Valley and
50s in the mountains which is still around 6 to 12 degrees above
normal for the beginning of February. Weak systems moving through
the fairly flat ridge will brush by the north bringing a chance of
precipitation this afternoon into Tuesday for the Northern
Sacramento Valley and surrounding mountains. Precipitation amounts
will be light with a quarter to half inch around Mt. Lassen and Shasta
County mountains, around 0.15 inches around Redding and less then
a tenth of an inch south of Redding in the Valley to around Chico.
Ridge builds up some on Wednesday ahead of a trough. The ridge
will bring a dry day and warmer temperatures up north with less
cloud cover. Patchy Valley fog is expected again in the morning.
The approaching trough may bring wet weather Thursday into the
weekend for Northern California.

.Extended Discussion (Thursday through Sunday)

No major changes in the models for the extended period continues
to lend confidence toward a return of wet weather for much of the
region later this week.

Ridge of high pressure still forecast to shift east into the
Rockies late this week as trough over the Gulf of Alaska edges a
bit closer. Models continue to forecast a period of very moist
southwesterly flow into NorCal late in the week and next weekend
(TPW plume in excess of 1.5 inches).

Heaviest QPF still forecast over northwest California with a shot
of decent precipitation likely extending south to around I-80
Friday into Saturday as strong upper jet noses onto the west coast
and IVT increases to well above normal.

&&

.Aviation...

VFR conditions across interior NorCal except for a band of dense
fog located along waterways. This is mainly impacting the Delta,
just west of KSMF and extending southward into the northern San
Joaquin Valley impacting KMOD with LIFR/IFR conditions. This is
dispersing by around 17-18Z, with lingering BR/HZ. Light
northerly winds this morning shifting to light southerly in the
afternoon. Disturbances passing to the north will bring increasing
mid and high clouds with shower chances limited to the northern
mountains.

&&

.STO Watches/Warnings/Advisories...
dense fog advisory until 10 am pst this morning carquinez strait
and delta...northern san joaquin valley...southern sacramento
valley.

&&

$$









000
FXUS66 KSTO 011649
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
849 AM PST Sun Feb 1 2015

.Synopsis...
Light precipitation possible in far northern portions late today
through Tuesday night. Above normal temperatures still expected
next week. Night and morning fog possible in the Central Valley
today into early next week. Increasing confidence in wet pattern
returning late in the week.

&&

.Short Term Discussion (Today through Wednesday)...
Patchy Dense Fog in the Northern San Joaquin and Delta area
and West of Sacramento this morning. Dense Fog reported at Davis,
Vacaville and Fairfield and Stockton with visibilities less than a
quarter of a mile at 8 am. Dense fog advisory out until 10 am this
morning. Visibilities should start increasing around 10 am as the
fog and low clouds dissipate. Patchy fog is expected to return to
areas around Sacramento, Delta and the Northern San Joaquin Valley
again the next few mornings.

High pressure weakens over the area with flattening ridge the next few
days bringing cooler temperatures (but still generally 5 to 10
degrees above normal) and possibly some precipitation to the
Northern portion of the Sacramento Valley and surrounding
mountains. The most cooling will be today with temperatures around
5 to 10 degrees cooler than yesterday due to high clouds and a
cooler air mass (850 mb temps drop around 3 degrees C). This will
bring afternoon temperatures down into the 60s in the Valley and
50s in the mountains which is still around 6 to 12 degrees above
normal for the beginning of February. Weak systems moving through
the fairly flat ridge will brush by the north bringing a chance of
precipitation this afternoon into Tuesday for the Northern
Sacramento Valley and surrounding mountains. Precipitation amounts
will be light with a quarter to half inch around Mt. Lassen and Shasta
County mountains, around 0.15 inches around Redding and less then
a tenth of an inch south of Redding in the Valley to around Chico.
Ridge builds up some on Wednesday ahead of a trough. The ridge
will bring a dry day and warmer temperatures up north with less
cloud cover. Patchy Valley fog is expected again in the morning.
The approaching trough may bring wet weather Thursday into the
weekend for Northern California.

.Extended Discussion (Thursday through Sunday)

No major changes in the models for the extended period continues
to lend confidence toward a return of wet weather for much of the
region later this week.

Ridge of high pressure still forecast to shift east into the
Rockies late this week as trough over the Gulf of Alaska edges a
bit closer. Models continue to forecast a period of very moist
southwesterly flow into NorCal late in the week and next weekend
(TPW plume in excess of 1.5 inches).

Heaviest QPF still forecast over northwest California with a shot
of decent precipitation likely extending south to around I-80
Friday into Saturday as strong upper jet noses onto the west coast
and IVT increases to well above normal.

&&

.Aviation...

VFR conditions across interior NorCal except for a band of dense
fog located along waterways. This is mainly impacting the Delta,
just west of KSMF and extending southward into the northern San
Joaquin Valley impacting KMOD with LIFR/IFR conditions. This is
dispersing by around 17-18Z, with lingering BR/HZ. Light
northerly winds this morning shifting to light southerly in the
afternoon. Disturbances passing to the north will bring increasing
mid and high clouds with shower chances limited to the northern
mountains.

&&

.STO Watches/Warnings/Advisories...
dense fog advisory until 10 am pst this morning carquinez strait
and delta...northern san joaquin valley...southern sacramento
valley.

&&

$$








000
FXUS66 KSTO 011649
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
849 AM PST Sun Feb 1 2015

.Synopsis...
Light precipitation possible in far northern portions late today
through Tuesday night. Above normal temperatures still expected
next week. Night and morning fog possible in the Central Valley
today into early next week. Increasing confidence in wet pattern
returning late in the week.

&&

.Short Term Discussion (Today through Wednesday)...
Patchy Dense Fog in the Northern San Joaquin and Delta area
and West of Sacramento this morning. Dense Fog reported at Davis,
Vacaville and Fairfield and Stockton with visibilities less than a
quarter of a mile at 8 am. Dense fog advisory out until 10 am this
morning. Visibilities should start increasing around 10 am as the
fog and low clouds dissipate. Patchy fog is expected to return to
areas around Sacramento, Delta and the Northern San Joaquin Valley
again the next few mornings.

High pressure weakens over the area with flattening ridge the next few
days bringing cooler temperatures (but still generally 5 to 10
degrees above normal) and possibly some precipitation to the
Northern portion of the Sacramento Valley and surrounding
mountains. The most cooling will be today with temperatures around
5 to 10 degrees cooler than yesterday due to high clouds and a
cooler air mass (850 mb temps drop around 3 degrees C). This will
bring afternoon temperatures down into the 60s in the Valley and
50s in the mountains which is still around 6 to 12 degrees above
normal for the beginning of February. Weak systems moving through
the fairly flat ridge will brush by the north bringing a chance of
precipitation this afternoon into Tuesday for the Northern
Sacramento Valley and surrounding mountains. Precipitation amounts
will be light with a quarter to half inch around Mt. Lassen and Shasta
County mountains, around 0.15 inches around Redding and less then
a tenth of an inch south of Redding in the Valley to around Chico.
Ridge builds up some on Wednesday ahead of a trough. The ridge
will bring a dry day and warmer temperatures up north with less
cloud cover. Patchy Valley fog is expected again in the morning.
The approaching trough may bring wet weather Thursday into the
weekend for Northern California.

.Extended Discussion (Thursday through Sunday)

No major changes in the models for the extended period continues
to lend confidence toward a return of wet weather for much of the
region later this week.

Ridge of high pressure still forecast to shift east into the
Rockies late this week as trough over the Gulf of Alaska edges a
bit closer. Models continue to forecast a period of very moist
southwesterly flow into NorCal late in the week and next weekend
(TPW plume in excess of 1.5 inches).

Heaviest QPF still forecast over northwest California with a shot
of decent precipitation likely extending south to around I-80
Friday into Saturday as strong upper jet noses onto the west coast
and IVT increases to well above normal.

&&

.Aviation...

VFR conditions across interior NorCal except for a band of dense
fog located along waterways. This is mainly impacting the Delta,
just west of KSMF and extending southward into the northern San
Joaquin Valley impacting KMOD with LIFR/IFR conditions. This is
dispersing by around 17-18Z, with lingering BR/HZ. Light
northerly winds this morning shifting to light southerly in the
afternoon. Disturbances passing to the north will bring increasing
mid and high clouds with shower chances limited to the northern
mountains.

&&

.STO Watches/Warnings/Advisories...
dense fog advisory until 10 am pst this morning carquinez strait
and delta...northern san joaquin valley...southern sacramento
valley.

&&

$$








000
FXUS66 KSTO 011144
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
344 AM PST Sun Feb 1 2015

.Synopsis...
Light precipitation possible in far northern portions late today
through Tuesday night. Above normal temperatures still expected
next week. Night and morning fog possible in the Central Valley
today into early next week. Increasing confidence in wet pattern
returning late in the week.

&&

.Short Term Discussion (Today through Wednesday)...
A weak system will move into the Pacific Northwest today. The
tail end will skirt the far northern sections of the state and may
bring a little precipitation through Tuesday to the northern half
of the Sacramento valley and surrounding mountains. The flattening
ridge and increase in high cloud cover will result in several
degrees of cooling over our forecast area today, generally 5-10
degrees.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley with variable mid to high cloudiness.

The disturbances move through by Wednesday, pumping up the ridge
in their wake before troughing takes hold again late in the week.
JClapp/JHM

&&

.Extended Discussion (Thursday through Sunday)
No major changes in the models for the extended period continues
to lend confidence toward a return of wet weather for much of the
region later this week.

Ridge of high pressure still forecast to shift east into the
Rockies late this week as trough over the Gulf of Alaska edges a
bit closer. Models continue to forecast a period of very moist
southwesterly flow into NorCal late in the week and next weekend
(TPW plume in excess of 1.5 inches).

Heaviest QPF still forecast over northwest California with a shot
of decent precipitation likely extending south to around I-80
Friday into Saturday as strong upper jet noses onto the west coast
and IVT increases to well above normal.

&&

.Aviation...
VFR conditions across interior NorCal except for local MVFR/IFR
in the Central Valley from KSMF southward until about 17Z. Lighter
north to east winds today compared to 24 hours ago. Disturbances
passing to the north will bring increasing mid and high clouds
with shower chances limited to the northern mountains.

&&

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

$$








000
FXUS66 KSTO 011144
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
344 AM PST Sun Feb 1 2015

.Synopsis...
Light precipitation possible in far northern portions late today
through Tuesday night. Above normal temperatures still expected
next week. Night and morning fog possible in the Central Valley
today into early next week. Increasing confidence in wet pattern
returning late in the week.

&&

.Short Term Discussion (Today through Wednesday)...
A weak system will move into the Pacific Northwest today. The
tail end will skirt the far northern sections of the state and may
bring a little precipitation through Tuesday to the northern half
of the Sacramento valley and surrounding mountains. The flattening
ridge and increase in high cloud cover will result in several
degrees of cooling over our forecast area today, generally 5-10
degrees.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley with variable mid to high cloudiness.

The disturbances move through by Wednesday, pumping up the ridge
in their wake before troughing takes hold again late in the week.
JClapp/JHM

&&

.Extended Discussion (Thursday through Sunday)
No major changes in the models for the extended period continues
to lend confidence toward a return of wet weather for much of the
region later this week.

Ridge of high pressure still forecast to shift east into the
Rockies late this week as trough over the Gulf of Alaska edges a
bit closer. Models continue to forecast a period of very moist
southwesterly flow into NorCal late in the week and next weekend
(TPW plume in excess of 1.5 inches).

Heaviest QPF still forecast over northwest California with a shot
of decent precipitation likely extending south to around I-80
Friday into Saturday as strong upper jet noses onto the west coast
and IVT increases to well above normal.

&&

.Aviation...
VFR conditions across interior NorCal except for local MVFR/IFR
in the Central Valley from KSMF southward until about 17Z. Lighter
north to east winds today compared to 24 hours ago. Disturbances
passing to the north will bring increasing mid and high clouds
with shower chances limited to the northern mountains.

&&

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

$$









000
FXUS66 KSTO 010645 CCA
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
950 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure and adiabatic warming from breezy Nly winds
brought record/near record max temps to interior Norcal today.

Some records for today (1/31):
Redding Airport 75 set in 2009.........76 today
(78 Redding city record in 1962)
Red Bluff 77 set in 2009..............75 today
Downtown Sacramento 74 set in 1976....73 today
Sacramento Exec 70 set in 1976........74 today
Stockton 70 set in 1976...............70 today
Modesto 70 set in 1976................68 today

A system will be moving into the Pacific Northwest Sunday. The tail
end will skirt the far northern sections of the state and may bring
a little precipitation through Tuesday to the northern half of the
Sacramento valley and surrounding mountains. The flattening ridge
and increase in high cloud cover will result in several degrees of
cooling over our CWA...generally 5-10 degrees. We may need to lower
Max temps especially across the Nrn zones for the Sun morning
issuance.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley.

Low level/surface flow has turned SEly from the central Sac Vly Swd
into the Nrn San Joaquin valley where dewpoints may recover
sufficiently by morning for some patchy stratus/fog. Higher
resolution RH progs suggest the best area would roughly be from
KMOD-KSCK-KSAC-KSMF and continuing Nwd along I-5 to around Tisdale.
Downslope flow over the Siernev will keep the Ern SAC suburbs and
Motherlode ST/Fog free.    /JHM


&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heels of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$










000
FXUS66 KSTO 010645 CCA
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
950 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure and adiabatic warming from breezy Nly winds
brought record/near record max temps to interior Norcal today.

Some records for today (1/31):
Redding Airport 75 set in 2009.........76 today
(78 Redding city record in 1962)
Red Bluff 77 set in 2009..............75 today
Downtown Sacramento 74 set in 1976....73 today
Sacramento Exec 70 set in 1976........74 today
Stockton 70 set in 1976...............70 today
Modesto 70 set in 1976................68 today

A system will be moving into the Pacific Northwest Sunday. The tail
end will skirt the far northern sections of the state and may bring
a little precipitation through Tuesday to the northern half of the
Sacramento valley and surrounding mountains. The flattening ridge
and increase in high cloud cover will result in several degrees of
cooling over our CWA...generally 5-10 degrees. We may need to lower
Max temps especially across the Nrn zones for the Sun morning
issuance.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley.

Low level/surface flow has turned SEly from the central Sac Vly Swd
into the Nrn San Joaquin valley where dewpoints may recover
sufficiently by morning for some patchy stratus/fog. Higher
resolution RH progs suggest the best area would roughly be from
KMOD-KSCK-KSAC-KSMF and continuing Nwd along I-5 to around Tisdale.
Downslope flow over the Siernev will keep the Ern SAC suburbs and
Motherlode ST/Fog free.    /JHM


&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heels of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$










000
FXUS66 KSTO 010645 CCA
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
950 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure and adiabatic warming from breezy Nly winds
brought record/near record max temps to interior Norcal today.

Some records for today (1/31):
Redding Airport 75 set in 2009.........76 today
(78 Redding city record in 1962)
Red Bluff 77 set in 2009..............75 today
Downtown Sacramento 74 set in 1976....73 today
Sacramento Exec 70 set in 1976........74 today
Stockton 70 set in 1976...............70 today
Modesto 70 set in 1976................68 today

A system will be moving into the Pacific Northwest Sunday. The tail
end will skirt the far northern sections of the state and may bring
a little precipitation through Tuesday to the northern half of the
Sacramento valley and surrounding mountains. The flattening ridge
and increase in high cloud cover will result in several degrees of
cooling over our CWA...generally 5-10 degrees. We may need to lower
Max temps especially across the Nrn zones for the Sun morning
issuance.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley.

Low level/surface flow has turned SEly from the central Sac Vly Swd
into the Nrn San Joaquin valley where dewpoints may recover
sufficiently by morning for some patchy stratus/fog. Higher
resolution RH progs suggest the best area would roughly be from
KMOD-KSCK-KSAC-KSMF and continuing Nwd along I-5 to around Tisdale.
Downslope flow over the Siernev will keep the Ern SAC suburbs and
Motherlode ST/Fog free.    /JHM


&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heels of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$











000
FXUS66 KSTO 010551
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
950 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure and adiabatic warming from breezy Nly winds
brought record/near record max temps to interior Norcal today.

Some records for today (1/31):
Redding Airport 75 set in 2009.........76 today
(78 Redding city record in 1962)
Red Bluff 77 set in 2009..............75 today
Downtown Sacramento 74 set in 1976....73 today
Sacramento Exec 70 set in 1976........74 today
Stockton 70 set in 1976...............70 today
Modesto 70 set in 1976................68 today

A system will be moving into the Pacific Northwest Sunday. The tail
end will skirt the far northern sections of the state and may bring
a little precipitation through Tuesday to the northern half of the
Sacramento valley and surrounding mountains. The flattening ridge
and increase in high cloud cover will result in several degrees of
cooling over our CWA...generally 5-10 degrees. We may need to lower
Max temps especially across the Nrn zones for the Sun morning
issuance.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley.

Low level/surface flow has turned SEly from the central Sac Vly Swd
into the Nrn San Joaquin valley where dewpoints may recover
sufficiently by morning for some patchy stratus/fog. Higher
resolution RH progs suggest the best area would roughly be from
KMOD-KSCK-KSAC-KSMF and continuing Nwd along I-5 to around Tisdale.
Downslope flow over the Siernev will keep the Ern SAC suburbs and
Motherlode ST/Fog free.    /JHM


&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heals of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$










000
FXUS66 KSTO 010551
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
950 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure and adiabatic warming from breezy Nly winds
brought record/near record max temps to interior Norcal today.

Some records for today (1/31):
Redding Airport 75 set in 2009.........76 today
(78 Redding city record in 1962)
Red Bluff 77 set in 2009..............75 today
Downtown Sacramento 74 set in 1976....73 today
Sacramento Exec 70 set in 1976........74 today
Stockton 70 set in 1976...............70 today
Modesto 70 set in 1976................68 today

A system will be moving into the Pacific Northwest Sunday. The tail
end will skirt the far northern sections of the state and may bring
a little precipitation through Tuesday to the northern half of the
Sacramento valley and surrounding mountains. The flattening ridge
and increase in high cloud cover will result in several degrees of
cooling over our CWA...generally 5-10 degrees. We may need to lower
Max temps especially across the Nrn zones for the Sun morning
issuance.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the central
part of the valley.

Low level/surface flow has turned SEly from the central Sac Vly Swd
into the Nrn San Joaquin valley where dewpoints may recover
sufficiently by morning for some patchy stratus/fog. Higher
resolution RH progs suggest the best area would roughly be from
KMOD-KSCK-KSAC-KSMF and continuing Nwd along I-5 to around Tisdale.
Downslope flow over the Siernev will keep the Ern SAC suburbs and
Motherlode ST/Fog free.    /JHM


&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heals of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$










000
FXUS66 KSTO 312249
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
249 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure today will bring record and near record heat
to the interior. Breezy northerly winds will decrease this evening
and become light.

Some records for today:
Redding 75 set in 2009
Red Bluff 77 set in 2009
Downtown Sacramento 74 set in 1976
Sacramento Exec 70 set in 1976
Stockton 70 set in 1976
Modesto 70 set in 1976

Sacramento Executive Airport has broken the old record and is
currently at 73 degrees. A system will be moving into the Pacific
Northwest Sunday. The tail end will skirt the far northern
sections of the state and may bring a little precipitation through
Tuesday to the northern half of the Sacramento valley and
surrounding mountains.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the
central part of the valley.

&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heals of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$








000
FXUS66 KSTO 312249
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
249 PM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Above normal temperatures expected to continue
next week. Night and morning fog possible in the Central Valley
Sunday into early next week. Models suggest change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure today will bring record and near record heat
to the interior. Breezy northerly winds will decrease this evening
and become light.

Some records for today:
Redding 75 set in 2009
Red Bluff 77 set in 2009
Downtown Sacramento 74 set in 1976
Sacramento Exec 70 set in 1976
Stockton 70 set in 1976
Modesto 70 set in 1976

Sacramento Executive Airport has broken the old record and is
currently at 73 degrees. A system will be moving into the Pacific
Northwest Sunday. The tail end will skirt the far northern
sections of the state and may bring a little precipitation through
Tuesday to the northern half of the Sacramento valley and
surrounding mountains.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the
central part of the valley.

&&

.Extended Discussion (Wednesday through Saturday)

Ridge of high pressure will be over the region on Wednesday. Some
moisture will continue to ride over the top of the ridge and into
the Pacific Northwest. The ridge will begin to shift to the east
on Thursday and a low pressure system may start to bring
precipitation along the coastal range Thursday afternoon or
Evening. The European model is a little faster with the timing of
this system. Expecting the main part of the storm to impact the
area Friday and Friday night. There may be another system on the
heals of this one Saturday night and Sunday. This system may be
able to bring much needed and decent amounts of rainfall for places
north of I-80. Unfortunately the snow level looks like it will be
very high so only the peaks may end up with snow.


&&

.Aviation...

VFR conditions across interior Norcal except for local MVFR/IFR
developing aft 06z-12z Sun from KSMF Swd into the the Nrn San
Joaquin Valley and Wwd into Solano Co. N winds 10-20 kt along the
Nrn and Wrn Sacramento Valley will diminish to nearly calm in the
Vly overnight. NE winds 25-35 kts also decreasing to light to
moderate Ely flow mainly 5-15 kts overnight.

High pressure over Norcal weakens overnite allowing high cloudiness
with bases AOA 12-15 kft to gradually spread SEwd over Norcal late
tonight and Sun.

&&

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

$$









000
FXUS66 KSTO 311721
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
921 AM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Some breezy north to east wind continues into
early afternoon with above normal temperatures. Night and morning
fog possible in the Central Valley Sunday into early next week.
Models suggest change to a potentially wet weather pattern towards
the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure today will bring record and near record heat
to the interior. A system will be moving into the Pacific
Northwest Sunday. The tail end will skirt the far northern
sections of the state may bring a little precipitation through
Tuesday to the northern half of the Sacramento valley and
surrounding mountains.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the
central part of the valley.

&&

.Extended Discussion (Wednesday through Saturday)

Upper ridge centered along the west coast at mid-week is forecast
to shift into the Rockies by the end of the week setting up a
period of moist southwesterly flow across the area late in the
week. Relative measure of predictability of the large-scale
features (ridge over the Rockies and trough over the Gulf of
Alaska) is high, so confidence in the pattern developing toward
wet late next week is continuing to increase.

Models depict a wide swath of deep TPW (in excess of 1.5 inches)
extending into NorCal late in the week with increasingly strong
forcing coming into play by Friday. At this time, appears the
heaviest QPF is still centered mainly north of I-80 by the GFS.
We`ll continue to monitor trends.

&&

.Aviation...

Mainly VFR conditions across interior NorCal next 24 hours, except
local MVFR/IFR conditions in the Northern San Joaquin Valley early
this morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through midday, then diminish. Over higher
terrain, areas NE winds 25-35 kts decreasing this afternoon.

&&

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

$$









000
FXUS66 KSTO 311721
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
921 AM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Some breezy north to east wind continues into
early afternoon with above normal temperatures. Night and morning
fog possible in the Central Valley Sunday into early next week.
Models suggest change to a potentially wet weather pattern towards
the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Strong high pressure today will bring record and near record heat
to the interior. A system will be moving into the Pacific
Northwest Sunday. The tail end will skirt the far northern
sections of the state may bring a little precipitation through
Tuesday to the northern half of the Sacramento valley and
surrounding mountains.

For the Sacramento region and areas southward expect conditions to
remain dry with patches of night and morning fog through the
central part of the valley.

&&

.Extended Discussion (Wednesday through Saturday)

Upper ridge centered along the west coast at mid-week is forecast
to shift into the Rockies by the end of the week setting up a
period of moist southwesterly flow across the area late in the
week. Relative measure of predictability of the large-scale
features (ridge over the Rockies and trough over the Gulf of
Alaska) is high, so confidence in the pattern developing toward
wet late next week is continuing to increase.

Models depict a wide swath of deep TPW (in excess of 1.5 inches)
extending into NorCal late in the week with increasingly strong
forcing coming into play by Friday. At this time, appears the
heaviest QPF is still centered mainly north of I-80 by the GFS.
We`ll continue to monitor trends.

&&

.Aviation...

Mainly VFR conditions across interior NorCal next 24 hours, except
local MVFR/IFR conditions in the Northern San Joaquin Valley early
this morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through midday, then diminish. Over higher
terrain, areas NE winds 25-35 kts decreasing this afternoon.

&&

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

$$








000
FXUS66 KSTO 311123
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
323 AM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Some breezy north to east wind continues into
Saturday with above normal temperatures. Night and morning fog
possible in the Central Valley Sunday into early next week.
Models suggest change to a potentially wet weather pattern towards
the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Positive-tilt upper ridging continues to build over NorCal today
as upper low to the south digs southeastward. The N-S low level
pressure gradient becomes more E-W dominated today. This will
favor stronger winds over the eastern foothills/mountains and
along the west side of the Sacramento Valley into the Delta.
The airmass undergoes synoptic warming today with increasing
heights/thicknesses. Highs tomorrow approach near records in the
Sacramento Valley with readings in the low to mid 70s. Yesterday
Sacramento Executive Airport tied a record of 69F, set in 1976.

Upper ridging flattens some Sunday as impulses ride over the top of
it into the PacNW. Greater area of morning valley fog possible in
the San Joaquin and possibly into the Southern Sacramento Valley and
Delta Sunday under lighter surface wind and increased subsidence.
Some associated overrunning cloudiness Sunday and Monday will
result in slight cooling over Interior NorCal. Models depict
potential for some light overrunning precip over mainly
Shasta/Plumas/Tehama counties Sunday night into Tuesday.

PCH/JClapp

&&

.Extended Discussion (Wednesday through Saturday)
Upper ridge centered along the west coast at mid-week is forecast
to shift into the Rockies by the end of the week setting up a
period of moist southwesterly flow across the area late in the
week. Relative measure of predictability of the large-scale
features (ridge over the Rockies and trough over the Gulf of
Alaska) is high, so confidence in the pattern developing toward
wet late next week is continuing to increase.

Models depict a wide swath of deep TPW (in excess of 1.5 inches)
extending into NorCal late in the week with increasingly strong
forcing coming into play by Friday. At this time, appears the
heaviest QPF is still centered mainly north of I-80 by the GFS.
We`ll continue to monitor trends.

&&

.Aviation...
Mainly VFR conditions across interior NorCal next 24 hours,
except local MVFR/IFR conditions in the Northern San Joaquin
Valley early this morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through midday, then diminish. Over higher
terrain, areas 25-35 kts decreasing this afternoon.

&&

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

$$








000
FXUS66 KSTO 311123
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
323 AM PST Sat Jan 31 2015

.Synopsis...
Light precipitation possible in far northern portions late Sunday
into Wednesday. Some breezy north to east wind continues into
Saturday with above normal temperatures. Night and morning fog
possible in the Central Valley Sunday into early next week.
Models suggest change to a potentially wet weather pattern towards
the end of next week.

&&

.Short Term Discussion (Today through Tuesday)...
Positive-tilt upper ridging continues to build over NorCal today
as upper low to the south digs southeastward. The N-S low level
pressure gradient becomes more E-W dominated today. This will
favor stronger winds over the eastern foothills/mountains and
along the west side of the Sacramento Valley into the Delta.
The airmass undergoes synoptic warming today with increasing
heights/thicknesses. Highs tomorrow approach near records in the
Sacramento Valley with readings in the low to mid 70s. Yesterday
Sacramento Executive Airport tied a record of 69F, set in 1976.

Upper ridging flattens some Sunday as impulses ride over the top of
it into the PacNW. Greater area of morning valley fog possible in
the San Joaquin and possibly into the Southern Sacramento Valley and
Delta Sunday under lighter surface wind and increased subsidence.
Some associated overrunning cloudiness Sunday and Monday will
result in slight cooling over Interior NorCal. Models depict
potential for some light overrunning precip over mainly
Shasta/Plumas/Tehama counties Sunday night into Tuesday.

PCH/JClapp

&&

.Extended Discussion (Wednesday through Saturday)
Upper ridge centered along the west coast at mid-week is forecast
to shift into the Rockies by the end of the week setting up a
period of moist southwesterly flow across the area late in the
week. Relative measure of predictability of the large-scale
features (ridge over the Rockies and trough over the Gulf of
Alaska) is high, so confidence in the pattern developing toward
wet late next week is continuing to increase.

Models depict a wide swath of deep TPW (in excess of 1.5 inches)
extending into NorCal late in the week with increasingly strong
forcing coming into play by Friday. At this time, appears the
heaviest QPF is still centered mainly north of I-80 by the GFS.
We`ll continue to monitor trends.

&&

.Aviation...
Mainly VFR conditions across interior NorCal next 24 hours,
except local MVFR/IFR conditions in the Northern San Joaquin
Valley early this morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through midday, then diminish. Over higher
terrain, areas 25-35 kts decreasing this afternoon.

&&

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

$$









000
FXUS66 KSTO 310540
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
940 PM PST Fri Jan 30 2015

.Synopsis...
Dry weather expected through the middle of next week except
for some mainly light precipitation possible in far northern
portions late Sunday into Wednesday. Some breezy north to east
wind continues into Saturday with above normal temperatures.
Night and morning fog possible in the Central Valley, becoming more
widespread Sunday into early next week. Models suggest a change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Monday)...
Surface high building into NWrn NV will maintain moderately strong
N and NE gradients tonite and into Sat morning to keep downslope
flow a factor in adiabatic warming and mixing. Have upped mins a few
degrees tonite...mainly in the Nrn Sac Vly and along the W side of
the Sac Vly in deference to a modest Nly barrier jet. Only a strip
of fog was evident this morning...and we expect even less coverage
Sat morning due to the Nly flow.  JHM

.Previous Discussion...

Upper ridging beginning to nose into the PacNW while surface ridging
extends into the Great Basin.

Upper ridging continues to build over NorCal tonight into Saturday
as upper low to the south digs. Low level pressure gradient
strengthens further tonight into early Saturday as it becomes more
E-W oriented over NorCal. This will favor stronger winds over the
eastern foothills/mountains and along the west side of the
Sacramento Valley into the Delta. AMS undergoes synoptic warming
tomorrow with increasing heights/thicknesses. Highs tomorrow
near record values in the Northern Sacramento Valley with
readings in the mid 70s, with upper 60s to lower 70s throughout
the remainder of the Central Valley.

Upper ridging flattens some Sunday as impulses ride over the top of
it into the PacNW. Greater area of morning valley fog possible in
the San Joaquin and possibly into the Southern Sacramento Valley and
Delta Sunday morning under lighter surface wind and increased
subsidence. Some associated overrunning cloudiness Sunday and
Monday will result in slight cooling over Interior NorCal. Models
depict potential for some light overrunning precip over mainly
Shasta county Sunday night into Monday.

PCH

&&

.Extended Discussion (Tuesday through Friday)

A flat ridge of high pressure will remain over most of the area
through the middle of next week, bringing continued dry weather. A
few weak impulses riding over the ridge could bring periods of
precipitation to northern CA, including Shasta County and Lassen
Park.

The more significant pattern change will occur late next week, as
the ridge shifts eastward and an Atmospheric River likely takes
aim at the West Coast. As with many AR events, the plume of
moisture is generally relatively narrow, and the biggest factor of
uncertainty is where the hose is pointed. The latest series of
model runs has this pointed at Northern California Friday through
Sunday. With confidence increasing in the potential for
precipitation toward next weekend, we increased our forecast
chances of precipitation quite a bit.

Dang


&&

.Aviation...

Mainly VFR conditions across interior Northern California the next
24 hours, except local MVFR/IFR conditions in the Northern San
Joaquin Valley early Saturday morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through mid-Saturday then diminish. Over the
Sierra...northeast winds will increase to 15-25 kt tonight, with
locally higher gusts.

Dang


&&

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

$$











000
FXUS66 KSTO 310540
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
940 PM PST Fri Jan 30 2015

.Synopsis...
Dry weather expected through the middle of next week except
for some mainly light precipitation possible in far northern
portions late Sunday into Wednesday. Some breezy north to east
wind continues into Saturday with above normal temperatures.
Night and morning fog possible in the Central Valley, becoming more
widespread Sunday into early next week. Models suggest a change to a
potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Monday)...
Surface high building into NWrn NV will maintain moderately strong
N and NE gradients tonite and into Sat morning to keep downslope
flow a factor in adiabatic warming and mixing. Have upped mins a few
degrees tonite...mainly in the Nrn Sac Vly and along the W side of
the Sac Vly in deference to a modest Nly barrier jet. Only a strip
of fog was evident this morning...and we expect even less coverage
Sat morning due to the Nly flow.  JHM

.Previous Discussion...

Upper ridging beginning to nose into the PacNW while surface ridging
extends into the Great Basin.

Upper ridging continues to build over NorCal tonight into Saturday
as upper low to the south digs. Low level pressure gradient
strengthens further tonight into early Saturday as it becomes more
E-W oriented over NorCal. This will favor stronger winds over the
eastern foothills/mountains and along the west side of the
Sacramento Valley into the Delta. AMS undergoes synoptic warming
tomorrow with increasing heights/thicknesses. Highs tomorrow
near record values in the Northern Sacramento Valley with
readings in the mid 70s, with upper 60s to lower 70s throughout
the remainder of the Central Valley.

Upper ridging flattens some Sunday as impulses ride over the top of
it into the PacNW. Greater area of morning valley fog possible in
the San Joaquin and possibly into the Southern Sacramento Valley and
Delta Sunday morning under lighter surface wind and increased
subsidence. Some associated overrunning cloudiness Sunday and
Monday will result in slight cooling over Interior NorCal. Models
depict potential for some light overrunning precip over mainly
Shasta county Sunday night into Monday.

PCH

&&

.Extended Discussion (Tuesday through Friday)

A flat ridge of high pressure will remain over most of the area
through the middle of next week, bringing continued dry weather. A
few weak impulses riding over the ridge could bring periods of
precipitation to northern CA, including Shasta County and Lassen
Park.

The more significant pattern change will occur late next week, as
the ridge shifts eastward and an Atmospheric River likely takes
aim at the West Coast. As with many AR events, the plume of
moisture is generally relatively narrow, and the biggest factor of
uncertainty is where the hose is pointed. The latest series of
model runs has this pointed at Northern California Friday through
Sunday. With confidence increasing in the potential for
precipitation toward next weekend, we increased our forecast
chances of precipitation quite a bit.

Dang


&&

.Aviation...

Mainly VFR conditions across interior Northern California the next
24 hours, except local MVFR/IFR conditions in the Northern San
Joaquin Valley early Saturday morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through mid-Saturday then diminish. Over the
Sierra...northeast winds will increase to 15-25 kt tonight, with
locally higher gusts.

Dang


&&

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

$$










000
FXUS66 KSTO 302240
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
240 PM PST Fri Jan 30 2015

.Synopsis...
Dry weather expected through the middle of next week except
for some mainly light precipitation possible in far northern
portions late Sunday into Wednesday. Some breezy north to east
wind continues into Saturday with above normal temperatures.
Night and morning fog possible in the Central Valley, becoming
more widespread Sunday into early next week. Models suggest change
to a potentially wet weather pattern towards the end of next week.

&&

.Short Term Discussion (Today through Monday)...
Water vapor imagery showing vort max sliding south along the
California coast ATTM is beginning to drop into backside of main
upper low and will help deepen and dig it over the next 24 hours.
Meanwhile upper ridging beginning to nose into the PacNW while
surface ridging extends into the Great Basin. KMFR-KRDD surface
pressure gradient is at 8.1 MB as KRDD-KSAC gradient is beginning
to trend up. Breezy conditions occurring in portions of the
Northern half of the Sacramento Valley with the strongest winds
observed so far at KRDD, speeds there are near low end advisory
criteria. Wind is trending up throughout the remainder of the
Sacramento and Northern San Joaquin valleys. Increased mixing will
help lower dew points and hinder fog development tonight. Expect
fog formation limited to patchy in our portion of the San Joaquin
valley Saturday morning.

Upper ridging continues to build over NorCal tonight into Saturday
as upper low to the south digs. Low level pressure gradient
strengthens further tonight into early Saturday as it becomes more
E-W oriented over NorCal. This will favor stronger winds over the
eastern foothills/mountains and along the west side of the
Sacramento Valley into the Delta. AMS undergoes synoptic warming
tomorrow with increasing heights/thicknesses. Highs tomorrow
near record values in the Northern Sacramento Valley with
readings in the mid 70s, with upper 60s to lower 70s throughout
the remainder of the Central Valley.

Upper ridging flattens some Sunday as impulses ride over the top of
it into the PacNW. Greater area of morning valley fog possible in
the San Joaquin and possibly into the Southern Sacramento Valley and
Delta Sunday morning under lighter surface wind and increased
subsidence. Some associated overrunning cloudiness Sunday and
Monday will result in slight cooling over Interior NorCal. Models
depict potential for some light overrunning precip over mainly
Shasta county Sunday night into Monday.

PCH

&&

.Extended Discussion (Tuesday through Friday)

A flat ridge of high pressure will remain over most of the area
through the middle of next week, bringing continued dry weather. A
few weak impulses riding over the ridge could bring periods of
precipitation to northern CA, including Shasta County and Lassen
Park.

The more significant pattern change will occur late next week, as
the ridge shifts eastward and an Atmospheric River likely takes
aim at the West Coast. As with many AR events, the plume of
moisture is generally relatively narrow, and the biggest factor of
uncertainty is where the hose is pointed. The latest series of
model runs has this pointed at Northern California Friday through
Sunday. With confidence increasing in the potential for
precipitation toward next weekend, we increased our forecast
chances of precipitation quite a bit.

Dang


&&

.Aviation...

Mainly VFR conditions across interior Northern California the next
24 hours, except local MVFR/IFR conditions in the Northern San
Joaquin Valley early Saturday morning.

North winds 10-20 kt along the northern and western Sacramento
Valley will continue through mid-Saturday then diminish. Over the
Sierra...northeast winds will increase to 15-25 kt tonight, with
locally higher gusts.

Dang


&&

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

$$








000
FXUS66 KSTO 301650
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
850 AM PST Fri Jan 30 2015

.Synopsis...
Mainly dry weather expected into the weekend with local night and
morning valley fog and above normal temperatures. Some breezy north
wind today into Saturday. A slight chance of showers northern areas
Monday and Tuesday...otherwise mostly dry weather likely to continue
through mid week. A chance of precipitation over much of northern
California is possible towards the end of next week.

&&

.Short Term Discussion (Today through Monday)...
Areas of fog developed again this morning in the Northern San
Joaquin Valley with patchy fog in the Southern Sacramento Valley.
The fog is not as dense as yesterday morning and is expected to
dissipate later this morning. Upper low off the SoCal coast attm
with short wave, currently over the Bay area, dropping south towards
the low will help deepen it over the next 24 hours. Lingering
cloudiness near the Sierra Nevada crest today but any light shower
activity expected to remain outside of the forecast area. Meanwhile
upper ridging beginning to nose into the PacNW while surface ridging
extends into the Great Basin. KMFR-KRDD surface pressure gradient is
trending up which will result in some breezy north to east wind
today. Wind speeds already in the teens in the Northern Sacramento
Valley with speeds expected to trend up farther southward in the
Central Valley by the afternoon. High temperatures today expected
to be similar to Thursday.

Upper ridging continues to build over NorCal tonight into Saturday
as upper low to the south digs. Low level pressure gradient
strengthens further tonight into early Saturday as it becomes more
E-W oriented over NorCal. This will favor stronger winds over the
eastern foothills/mountains and along the west side of the
Sacramento Valley into the Delta. Any fog that develops Saturday
morning will be limited to the San Joaquin Valley. AMS undergoes
synoptic warming Saturday with increasing heights/thicknesses. Highs
tomorrow approach near records in the Northern Sacramento Valley
with readings in the mid 70s, with upper 60s to lower 70s throughout
the remainder of the Central Valley.

Upper ridging flattens some Sunday as impulses ride over the top of
it into the PacNW. Greater area of morning valley fog possible in
the San Joaquin and possibly into the Southern Sacramento Valley and
Delta Sunday under lighter surface wind and increased subsidence.
Some associated overrunning cloudiness Sunday will result in slight
cooling over Interior NorCal. Models depict potential for some light
overrunning precip over mainly Shasta county Sunday night into
Monday.

PCH

&&

.Extended Discussion (Tuesday through Friday)

The ridge is flattened enough Tuesday to potentially allow the
southern periphery of a trough to bring a slight chance of light
rain to Shasta county. But that`s as far south as the rain
extends. The dominant ridge builds back up over the west coast
Wednesday, keeping the area dry.

However, a broad, deep upper trough is taking shape over the
eastern Pacific. The models show promising signs of the upper ridge
shifting into inter-mountain west, allowing the trough to creep
closer to the coast with increased chances of much needed
precipitation late Thursday through Friday. This system is
looking like an Atmospheric River (AR) event, but the main swath of
moisture still looks to remain just north of our forecast area on
Friday, across northwest California and western Oregon. We need
the ridge to continue to shift east to allow the AR to settle over
California.    JClapp

&&

.Aviation...

Genly VFR ovr Intr NorCal nxt 24 hrs exc lcl IFR/LIFR in fog til
arnd 19z this mrng in ptns of Srn Sac/Nrn San Joaquin vlys. Nly sfc
wnd gsts to 25 kts poss in Cntrl Vly this aftn.



&&

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

$$











000
FXUS66 KSTO 301126
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
326 AM PST Fri Jan 30 2015

.Synopsis...
Dry weather expected through the weekend with night and morning
valley fog and above normal temperatures. Some breezy north wind
today into Saturday. A slight chance of showers northern areas
Monday and Tuesday...otherwise mostly dry weather likely to continue
through mid week. A chance of precipitation much of northern
California the end of next week.

&&

.Discussion...
Axis of Weak trough now over California has shifted east of the
forecast area and should now be of little impact other than some
scattered clouds over the Sierra. Otherwise skies are clear this
morning as upper level high pressure begins pushing back inland.
Northerly surface gradient starting to develop over far Norcal as
surface high pressure system over the Pacific Northwest shifts
southward. Light north winds over the northern Sacramento valley
keeping north valley fog free. The rest of the valley is seeing
lighter winds this morning and as a result...patchy fog has
developed from about Sacramento southward. Fog has not become
significant yet but will need to watch for denser fog formation as
dense fog has formed just to the south of the CWA. Surface
gradient tightens this afternoon for breezy north to east winds
across most of the forecast area. At this time it appears
wind speeds will remain below advisory criteria. North to east
surface gradient maxes out across Norcal tonight with good upper
level support. Therefore...expect breezy to gusty north to east
winds to continue through the night although decoupling will bring
some decrease in winds some valley locations. Should keep enough
wind in the valley however to keep overnight valley fog to a
minimum. Winds drop off quickly on Saturday as upper level high
pressure ridge pushes inland and gradients relax. Overall airmass
warms under the ridge on Saturday so should see warmer daytime
highs most areas with close to record for the date high
temperatures expected.

Lighter winds Sunday morning will allow valley fog to push
northward again although light north winds will minimize fog
chances for the northern Sacramento valley. A shortwave trough
riding over the west coast ridge and into the Pacific Northwest
will bring cloud cover to most of the CWA during the day on
Sunday. Cloud cover and cooler airmass will bring cooler daytime
temperatures on Sunday. The tail end of this trough will bring a
slight threat of showers over Shasta county Sunday night and
Monday. Cloud cover will bring a bit more cooling elsewhere
although daytime highs will remain well above normal.

&&

.Extended Discussion (Tuesday through Friday)

The ridge is flatten enough Tuesday to potentially allow the
southern periphery of a trough to bring a slight chance of light
rain to Shasta county. But that`s as far south as the rain
extends. The dominant ridge builds back up over the west coast
Wednesday, keeping the area dry.

However, a broad, deep upper trough is taking shape over the
eastern Pacific. The models show promising signs of the upper ridge
shifting into inter-mountain west, allowing the trough to creep
closer to the coast with increased chances of much needed
precipitation late Thursday through Friday. This system is
looking like an Atmospheric River (AR) event, but the main swath of
moisture still looks to remain just north of our forecast area on
Friday, across northwest California and western Oregon. We need
the ridge to continue to shift east to allow the AR to settle over
California.    JClapp

&&

.Aviation...

Expect some patchy dense fog to develop this morning, most likely
around KSCK but also possible near Sacramento TAF sites.

North winds will increase to 5-15 kt by late morning/early
afternoon, spreading from north to south down the valley. Local
gusts up to 25 kt will be possible along the northern and western
Sacramento Valley after 20z.    JClapp


&&

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

$$








000
FXUS66 KSTO 301126
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
326 AM PST Fri Jan 30 2015

.Synopsis...
Dry weather expected through the weekend with night and morning
valley fog and above normal temperatures. Some breezy north wind
today into Saturday. A slight chance of showers northern areas
Monday and Tuesday...otherwise mostly dry weather likely to continue
through mid week. A chance of precipitation much of northern
California the end of next week.

&&

.Discussion...
Axis of Weak trough now over California has shifted east of the
forecast area and should now be of little impact other than some
scattered clouds over the Sierra. Otherwise skies are clear this
morning as upper level high pressure begins pushing back inland.
Northerly surface gradient starting to develop over far Norcal as
surface high pressure system over the Pacific Northwest shifts
southward. Light north winds over the northern Sacramento valley
keeping north valley fog free. The rest of the valley is seeing
lighter winds this morning and as a result...patchy fog has
developed from about Sacramento southward. Fog has not become
significant yet but will need to watch for denser fog formation as
dense fog has formed just to the south of the CWA. Surface
gradient tightens this afternoon for breezy north to east winds
across most of the forecast area. At this time it appears
wind speeds will remain below advisory criteria. North to east
surface gradient maxes out across Norcal tonight with good upper
level support. Therefore...expect breezy to gusty north to east
winds to continue through the night although decoupling will bring
some decrease in winds some valley locations. Should keep enough
wind in the valley however to keep overnight valley fog to a
minimum. Winds drop off quickly on Saturday as upper level high
pressure ridge pushes inland and gradients relax. Overall airmass
warms under the ridge on Saturday so should see warmer daytime
highs most areas with close to record for the date high
temperatures expected.

Lighter winds Sunday morning will allow valley fog to push
northward again although light north winds will minimize fog
chances for the northern Sacramento valley. A shortwave trough
riding over the west coast ridge and into the Pacific Northwest
will bring cloud cover to most of the CWA during the day on
Sunday. Cloud cover and cooler airmass will bring cooler daytime
temperatures on Sunday. The tail end of this trough will bring a
slight threat of showers over Shasta county Sunday night and
Monday. Cloud cover will bring a bit more cooling elsewhere
although daytime highs will remain well above normal.

&&

.Extended Discussion (Tuesday through Friday)

The ridge is flatten enough Tuesday to potentially allow the
southern periphery of a trough to bring a slight chance of light
rain to Shasta county. But that`s as far south as the rain
extends. The dominant ridge builds back up over the west coast
Wednesday, keeping the area dry.

However, a broad, deep upper trough is taking shape over the
eastern Pacific. The models show promising signs of the upper ridge
shifting into inter-mountain west, allowing the trough to creep
closer to the coast with increased chances of much needed
precipitation late Thursday through Friday. This system is
looking like an Atmospheric River (AR) event, but the main swath of
moisture still looks to remain just north of our forecast area on
Friday, across northwest California and western Oregon. We need
the ridge to continue to shift east to allow the AR to settle over
California.    JClapp

&&

.Aviation...

Expect some patchy dense fog to develop this morning, most likely
around KSCK but also possible near Sacramento TAF sites.

North winds will increase to 5-15 kt by late morning/early
afternoon, spreading from north to south down the valley. Local
gusts up to 25 kt will be possible along the northern and western
Sacramento Valley after 20z.    JClapp


&&

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

$$









000
FXUS66 KSTO 300609
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
1005 PM PST Thu Jan 29 2015

.Synopsis...
Dry weather expected into the weekend with night and morning
valley fog and above normal temperatures. Some breezy wind
possible Friday into Saturday. A slight chance of showers northern
areas Monday...otherwise mostly dry weather likely to continue
through mid week.

&&

.Discussion...

Satellite imagery now shows stratocumulus banked-p along the E side
of the Siernev to the Crest. Given the current and forecast NEly
flow/trajectory from the upper air pattern...the clouds should
persist through Fri. Upper air impulse over the Pac NW forecast to
move over Norcal on Fri. This impulse will be associated with some
high cloud cover with the cyclonic circulation possibly triggering
some cumulus development over the Siernev during the afternoon
similar to today with a similar feature that tracked a little
farther W than Fri`s feature is forecast to track. Increasing Nly
flow is forecast with this feature mainly in the afternoon when
gusty/breezy Nly winds should develop over most of the CWA.

ST/Fog developing over MCE...likely to have a difficult time
spreading Nwd past the Nrn San Joaquin Vly Fri morning. Have limited
the Fog to Sac area Swd due to the Nly flow above the radiative
inversion.   JHM


.Previous Discussion...

Closed upper low deepens over SoCal Friday as EPAC upper ridging
builds into the PacNW. At surface, inverted trough extends
northward along the CA coast into OR as surface high builds into
the Great Basin. This pattern will result in some breezy N to E
winds over Interior NorCal Friday. Gradient suggests wind speeds
will generally remain below advisory criteria. Increase in low
level northerly flow Friday morning may help limit valley fog
development or allow for faster clearing for areas that do have
some.

Upper ridging builds into NorCal over the weekend with some breezy
wind continuing into Saturday, strongest along the west side of
the Sacramento Valley. Some patchy fog possible in our portion of
the San Joaquin Valley Saturday morning but should be limited.
More widespread valley fog possible Sunday under lighter surface
wind and increased subsidence. Above normal temperatures continue
over the weekend with highs ranging from upper 50s to lower 60s in
the Northern San Joaquin Valley to lower to mid 70s in the
Northern Sacramento Valley. Highs in the mountains and foothills
forecast in the 50s and 60s.

PCH

&&

.Extended Discussion (Monday through Thursday)

Models differ slightly in amplitude of ridging over NorCal
Monday...with Euro just flat enough to bring disturbance and
moisture into far northern California and the GFS keeping things
mainly dry. Will keep slight shower chances Coastal Range and
Shasta county Monday/Tuesday to blend with Euro and surrounding
offices. A stronger system is possible late Thursday into
Friday...especially over northern areas(Coastal Range/Shasta
county/Nrn Sierra). Temperatures will range from the low/upper
60`d through the period warmest north.

&&

.Aviation...

VFR conditions with generally light winds are prevalent this
afternoon across northern California. Expect some patchy dense fog
to redevelop again tonight into Friday morning, mostly likely
around KSCK but also possible near Sacramento TAF sites.

Light north winds will increase to 5-15 kt by mid to late Friday
morning. Local gusts up to 25 kt will be possible along the
northern and western Sacramento Valley after 18z Friday.

Dang


&&

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

$$













000
FXUS66 KSTO 300049 AAA
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
440 PM PST Thu Jan 29 2015

.Synopsis...
Dry weather expected into the weekend with night and morning
valley fog and above normal temperatures. Some breezy wind
possible Friday into Saturday. A slight chance of showers northern
areas Monday...otherwise mostly dry weather likely to continue
through mid week.

&&

UPDATED...

.Discussion...

Satellite imagery showing some CU developing along mountains of
Interior NorCal this afternoon in response to elongated upper
trough/low moving into the area. HRRR/local WRF-ARW showing
potential for a few showers from the Sierra Nevada crest eastward
and on the west slopes. UPDATED THE ZONES TO ACCOUNT FOR CLOUDS AND
ISOLATED TO SCATTERED SHOWERS ON OUR SIDE OF THE CREST THIS EVENING
IN DEFERENCE TO RADAR RETURNS AND HIGH RES MODEL QUIDANCE.
Otherwise...mostly clear skies expected for Interior NorCal
overnight with some fog returning for the San Joaquin Valley
overnight into Friday morning.

Closed upper low deepens over SoCal Friday as EPAC upper ridging
builds into the PacNW. At surface, inverted trough extends
northward along the CA coast into OR as surface high builds into
the Great Basin. This pattern will result in some breezy N to E
winds over Interior NorCal Friday. Gradient suggests wind speeds
will generally remain below advisory criteria. Increase in low
level northerly flow Friday morning may help limit valley fog
development or allow for faster clearing for areas that do have
some.

Upper ridging builds into NorCal over the weekend with some breezy
wind continuing into Saturday, strongest along the west side of
the Sacramento Valley. Some patchy fog possible in our portion of
the San Joaquin Valley Saturday morning but should be limited.
More widespread valley fog possible Sunday under lighter surface
wind and increased subsidence. Above normal temperatures continue
over the weekend with highs ranging from upper 50s to lower 60s in
the Northern San Joaquin Valley to lower to mid 70s in the
Northern Sacramento Valley. Highs in the mountains and foothills
forecast in the 50s and 60s.

PCH

&&

.Extended Discussion (Monday through Thursday)

Models differ slightly in amplitude of ridging over NorCal
Monday...with Euro just flat enough to bring disturbance and
moisture into far northern California and the GFS keeping things
mainly dry. Will keep slight shower chances Coastal Range and
Shasta county Monday/Tuesday to blend with Euro and surrounding
offices. A stronger system is possible late Thursday into
Friday...especially over northern areas(Coastal Range/Shasta
county/Nrn Sierra). Temperatures will range from the low/upper
60`d through the period warmest north.

&&

.Aviation...

VFR conditions with generally light winds are prevalent this
afternoon across northern California. Expect some patchy dense fog
to redevelop again tonight into Friday morning, mostly likely
around KSCK but also possible near Sacramento TAF sites.

Light north winds will increase to 5-15 kt by mid to late Friday
morning. Local gusts up to 25 kt will be possible along the
northern and western Sacramento Valley after 18z Friday.

Dang


&&

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

$$











000
FXUS66 KSTO 292300
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
300 PM PST Thu Jan 29 2015

.Synopsis...
Dry weather expected into the weekend with night and morning
valley fog and above normal temperatures. Some breezy wind
possible Friday into Saturday. A slight chance of showers northern
areas Monday...otherwise mostly dry weather likely to continue
through mid week.

&&

.Discussion...
Satellite imagery showing some CU developing along mountains of
Interior NorCal this afternoon in response to elongated upper
trough/low moving into the area. HRRR/local WRF-ARW showing
potential for some showers from Sierra Nevada crest eastward and
on the west slopes, south of our portion, near Yosemite through
this evening. Mostly clear skies expected for Interior NorCal
overnight with some fog returning for the San Joaquin Valley
overnight into Friday morning.

Closed upper low deepens over SoCal Friday as EPAC upper ridging
builds into the PacNW. At surface, inverted trough extends
northward along the CA coast into OR as surface high builds into
the Great Basin. This pattern will result in some breezy N to E
winds over Interior NorCal Friday. Gradient suggests wind speeds
will generally remain below advisory criteria. Increase in low
level northerly flow Friday morning may help limit valley fog
development or allow for faster clearing for areas that do have
some.

Upper ridging builds into NorCal over the weekend with some breezy
wind continuing into Saturday, strongest along the west side of
the Sacramento Valley. Some patchy fog possible in our portion of
the San Joaquin Valley Saturday morning but should be limited.
More widespread valley fog possible Sunday under lighter surface
wind and increased subsidence. Above normal temperatures continue
over the weekend with highs ranging from upper 50s to lower 60s in
the Northern San Joaquin Valley to lower to mid 70s in the
Northern Sacramento Valley. Highs in the mountains and foothills
forecast in the 50s and 60s.

PCH

&&

.Extended Discussion (Monday through Thursday)

Models differ slightly in amplitude of ridging over NorCal
Monday...with Euro just flat enough to bring disturbance and
moisture into far northern California and the GFS keeping things
mainly dry. Will keep slight shower chances Coastal Range and
Shasta county Monday/Tuesday to blend with Euro and surrounding
offices. A stronger system is possible late Thursday into
Friday...especially over northern areas(Coastal Range/Shasta
county/Nrn Sierra). Temperatures will range from the low/upper
60`d through the period warmest north.

&&

.Aviation...

VFR conditions with generally light winds are prevalent this
afternoon across northern California. Expect some patchy dense fog
to redevelop again tonight into Friday morning, mostly likely
around KSCK but also possible near Sacramento TAF sites.

Light north winds will increase to 5-15 kt by mid to late Friday
morning. Local gusts up to 25 kt will be possible along the
northern and western Sacramento Valley after 18z Friday.

Dang


&&

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

$$








000
FXUS66 KSTO 292300
AFDSTO

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
300 PM PST Thu Jan 29 2015

.Synopsis...
Dry weather expected into the weekend with night and morning
valley fog and above normal temperatures. Some breezy wind
possible Friday into Saturday. A slight chance of showers northern
areas Monday...otherwise mostly dry weather likely to continue
through mid week.

&&

.Discussion...
Satellite imagery showing some CU developing along mountains of
Interior NorCal this afternoon in response to elongated upper
trough/low moving into the area. HRRR/local WRF-ARW showing
potential for some showers from Sierra Nevada crest eastward and
on the west slopes, south of our portion, near Yosemite through
this evening. Mostly clear skies expected for Interior NorCal
overnight with some fog returning for the San Joaquin Valley
overnight into Friday morning.

Closed upper low deepens over SoCal Friday as EPAC upper ridging
builds into the PacNW. At surface, inverted trough extends
northward along the CA coast into OR as surface high builds into
the Great Basin. This pattern will result in some breezy N to E
winds over Interior NorCal Friday. Gradient suggests wind speeds
will generally remain below advisory criteria. Increase in low
level northerly flow Friday morning may help limit valley fog
development or allow for faster clearing for areas that do have
some.

Upper ridging builds into NorCal over the weekend with some breezy
wind continuing into Saturday, strongest along the west side of
the Sacramento Valley. Some patchy fog possible in our portion of
the San Joaquin Valley Saturday morning but should be limited.
More widespread valley fog possible Sunday under lighter surface
wind and increased subsidence. Above normal temperatures continue
over the weekend with highs ranging from upper 50s to lower 60s in
the Northern San Joaquin Valley to lower to mid 70s in the
Northern Sacramento Valley. Highs in the mountains and foothills
forecast in the 50s and 60s.

PCH

&&

.Extended Discussion (Monday through Thursday)

Models differ slightly in amplitude of ridging over NorCal
Monday...with Euro just flat enough to bring disturbance and
moisture into far northern California and the GFS keeping things
mainly dry. Will keep slight shower chances Coastal Range and
Shasta county Monday/Tuesday to blend with Euro and surrounding
offices. A stronger system is possible late Thursday into
Friday...especially over northern areas(Coastal Range/Shasta
county/Nrn Sierra). Temperatures will range from the low/upper
60`d through the period warmest north.

&&

.Aviation...

VFR conditions with generally light winds are prevalent this
afternoon across northern California. Expect some patchy dense fog
to redevelop again tonight into Friday morning, mostly likely
around KSCK but also possible near Sacramento TAF sites.

Light north winds will increase to 5-15 kt by mid to late Friday
morning. Local gusts up to 25 kt will be possible along the
northern and western Sacramento Valley after 18z Friday.

Dang


&&

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

$$









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