Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 010645 CCA
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
950 PM PST Sat Jan 31 2015
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
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.
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.