Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 221602
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
902 AM PDT Fri May 22 2015
Mild weather with mainly mountain showers and thunderstorms will
continue today. Warmer temperatures with scattered mountain showers
expected this weekend into next week.
A longwave trough remains situated along the West Coast, with
embedded closed upper low moving inland over Southern California.
Easterly flow off the Sierra this morning brought a few sprinkles
down into the southern Sacramento and northern San Joaquin
Valleys. Otherwise, weather is relatively quiet early this
morning with some reports of low clouds and locally dense fog
along the mountains.
Scattered afternoon and evening showers and thunderstorms will
continue over the mountains today and through the Memorial Day
Weekend. Upper level flow will be shifting to a northerly
direction today and through the weekend. Interestingly, the HRRR
is showing some showery development over the Shasta-Trinitys
advecting over the northern Valley later today. Otherwise, most of
the convection is likely to remain confined over the mountains
through the holiday weekend.
Seasonably cool temperatures will continue today under a moist
airmass. However, a slow and gradual warming trend is expected
through the holiday weekend. Temperatures should generally be
within a few degrees of normal for the weekend.
.Extended Discussion (Tuesday through Friday)
Trough pattern forecast to linger, albeit weaker, through the
extended period continuing a chance of daily diurnal deep
convection over the mountains while temperatures return to near
General VFR conditions expected next 24 hours except areas of MVFR
with local IFR conditions over the northern Sierra Nevada vicinity
showers. Scattered thunderstorms over the mountains 20Z-02Z.
Chance for MVFR ceilings in the Delta through about 17Z. Local
westerly wind gusts 20-25 kts after 20Z in the Delta and northern
San Joaquin Valley.