Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 241124
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
424 AM PDT Sun Aug 24 2014
High pressure will bring fair skies through the coming week.
Daytime temperatures near to slightly below normal today and
Monday. A little above normal daytime highs Tuesday through
Thursday. Cooler temperatures next weekend as a Pacific through
approaches the coast with a slight chance of precipitation over
the northern mountains.
Fair skies this morning under stable northwest flow between a low
pressure system over the Great Basin and a high pressure ridge
over the eastern Pacific. The marine layer is around 2000 feet
deep this morning with a moderate delta breeze. Some scattered
coastal stratus has moved into the delta this morning but will not
likely make a significant intrusion into the valley. A shortwave
trough dropping down the back side of the low and into the Pacific
northwest will bring a little cooler temperatures and a few high
clouds this afternoon. The high pressure ridge over the eastern
Pacific will slowly shift inland over the western U.S Monday
through Wednesday. This will bring fair skies and a little warmer
temperatures with daytime highs warming on Monday then
temperatures climbing to a few degrees above normal Tuesday and
Wednesday. Wednesday will likely be the warmest day of the week as
the upper ridge axis centers along the west coast.
.Extended Discussion (Thursday through Sunday)
Models begin shifting upper ridge into the Great Basin by
Thursday as a trough begins to form in the eastern Pacific. This
should bring the start of a slow cooling trend as the airmass
cools and a stronger onshore flow develops. This process should
continue on Friday with daytime highs dropping to near normal.
Extended models move the offshore trough into the Pacific
Northwest next Saturday and Sunday. 00Z run of the GFS deepened
this trough enough to produce precip to NORCAL but 06z more shallow
and more in line with the ECMWF and GEM which kept NORCAL dry.
Can not rule out threat of precip over Norcal next weekend but at
this point models indicating it is unlikely. Most likely impact
will be a continued cooling trend with daytime highs a little
One forecast that is a bit more certain is a loss of sleep for
many Sacramentans this morning due to an earthquake which occurred
at 3:20 this morning. The epicenter of this 6.0 earthquake was
reported by USGS 8 miles northwest of Vallejo in Napa county.
NWly flow alf ovr Intr NorCal with VFR conds nxt 24 hrs exc isold
MVFR/IFR conds poss in ST vcnty Delta til arnd 18z Sun. Lcl SW-NW
sfc wnd gsts to 30 kts poss ovr hyr mtn trrn and thru Delta this
aftn into eve.