Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 211616
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
916 AM PDT Thu Aug 21 2014
Weak trough over the west coast with northwest flow aloft will
bring dry conditions with a little below normal temperatures
through early next week. High pressure moving inland over the west
coast will bring warming to near or a little above normal during
the first half of next week.
High pressure over the Eastern Pacific and a trough over the
Pacific Northwest with Northern California in between them with
Northwest flow aloft today. Low clouds only made it inland to
around Cordelia and Rio Vista in the Delta region this morning
with not as deep of a marine layer (around 2000 ft) and weaker
onshore flow than yesterday morning. Warmer temperatures this
afternoon with higher pressure nudging into the area with weaker
onshore flow and a more shallow marine layer. Temperatures are
expected to be in the mid 80s to mid 90s in the Valley and low 60s
to low 80s in the mountains which is near to several degrees below
normal for this time of year. The upper level trough digs down
into far northern California tomorrow bringing a little cooler
temperatures across the north and breezy westerly winds over the
ridgetops. Temperatures will be similar to a little warmer on
Saturday and be about the same on Sunday as Northern California
lies between ridge of High pressure over the Eastern Pacific and a
trough over the Western U.S.
.Extended Discussion (Monday through Thursday)
An upper level high pressure ridge over the eastern Pacific will
slowly move inland over the western U.S. Monday through Wednesday.
During this timeframe expect fair skies and a slow warming trend.
By Wednesday...daytime highs should rise to right around normal
for this time of year. A fairly large discrepancy exists in the
extended models at this time however with the ECMWF digging a low
over NORCAL during this time as opposed to the ridge advertised by
the GFS and GEM models. Have gone with GFS/GEM solutions which
have had better run to run consistency in latest runs. These
models show a slight cool off towards the end of next week as a
new Pacific system approaches the Pacific Northwest.
NWly flow alf ovr Intr NorCal with VFR conds nxt 24 hrs exc lcl
MVFR/IFR conds poss in ST vcnty Delta til arnd 18z Thu. Lcl SWly
sfc wnd gsts to 25 kts poss ovr hyr mtn trrn and thru Delta this
aftn into eve.