Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 261055
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
355 AM PDT Tue May 26 2015
Gradually warmer temperatures this week with mainly afternoon and
evening mountain showers and thunderstorms through mid-week.
Strengthening high pressure brings warmer weather with high temps
peaking at 5 to 10 degrees above normal Thursday and Friday.
Continuing onshore flow along with a marine layer that remains
around 3000 ft deep is once again resulting in a stratus intrusion
into the Sacramento area early this morning. Elsewhere, skies are
clear to partly cloudy and temperatures are generally a little
cooler compared to 24 hours ago with readings in the 50s to lower
60s through most of the valley, the exception being the north end
of the valley where temperatures are currently in the mid 60s to
Very little change in the overall weather pattern is expected for
the region today as the closed low remains nearly stationary over
eastern Washington. The northern mountains and Sierra Nevada south
of Lake Tahoe may see some isolated late day showers and
thunderstorms and high temperatures are expected to be similar to
those of Memorial Day.
By Wednesday, the PacNW low is forecast to begin drifting east
into the northern Rockies, but may still have enough lingering
moisture and instability for an isolated storm near Mt Lassen and
south of Tahoe again. Temperatures will likely begin to warm
across the area as onshore gradients slacken.
After a hiatus for awhile, much warmer summer-like weather is
forecast to return to interior NorCal Thursday and Friday as the
upper ridge moves overhead. 850 mb temps forecast to climb into
the upper teens to lower 20s C, around 1-2 SD`s above normal, and
the northern Sacramento Valley may see high temperatures
approaching the century mark.
.Extended Discussion (Saturday through Tuesday)...
High pressure ridge will shift east on Saturday and Sunday into
the Great Basin in advance of next low pressure system. Dry
weather, mostly sunny skies, and above normal temperatures will
continue for the weekend. Daytime highs will be a few degrees
cooler from Saturday to Sunday as ridge axis shifts east. Next
system, currently around 150W, will slowly shift southeast into
NorCal by Monday. Models in better agreement over past few runs
with best chances for any precip across northern mountain but
moisture looks limited at this point. Regardless, this should
bring cooler temperatures for the start of the work week, with
daytime highs near or slightly below normal. CEO
Marine stratus has again intruded into the Delta and Sacramento
sites early this morning with locally MVFR cigs. Suspect this will
continue until around daybreak with stratus burning off by 16-18z.
Otherwise VFR conditions expected over next 24 hours across the
valley. A few showers and thunderstorms across higher terrain this
afternoon/evening may lead to brief MVFR restrictions. Delta
breeze will continue to cause locally gusty winds with gusts to 30