Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 251010
Area Forecast Discussion
National Weather Service Sacramento CA
310 AM PDT WED MAY 25 2016
Showers and isolated thunderstorms again today, mainly over the
higher elevations. Dry and warmer by the weekend.
Clear to partly cloudy skies across interior NorCal early this
morning. Current temperatures are mainly in the 30s and 40s in the
mountains with 50s elsewhere.
The large upper trough that has kept the cool and unsettled
weather pattern going across the region over the past several days
remains overhead NorCal, but most of the energy has consolidated
into a closed low that is now just off the SoCal coast near
Vandenberg. This low will move east into the lower Colorado River
Valley today before lifting out into the central Plains by the end
of the week, gradually replaced over NorCal by ridging from the
With the lack of a larger scale trigger, deep convection today
will likely remain mostly over and near higher terrain. There is
some potential that showers and thunderstorms that initiate over
the Coast Range this afternoon may propagate into western
portions of the valley (mostly to the west and northwest of
Sacramento) late in the day.
The trend will be for less mountain convection each day heading
into the holiday weekend with temperatures returning to around
average late-May readings.
.EXTENDED DISCUSSION (SUNDAY THROUGH WEDNESDAY)...
Mid-range models in general agreement in placing upper trough
axis east of the state by Sunday so have taken shower threat out
of all areas for second half of weekend. Daytime highs should
remain a little above normal Sunday under mainly fair skies.
Models remain in good agreement through the early part of next
week in sliding upper ridge over the west coast for continued fair
and dry conditions. Daytime highs will continue to creep up
reaching to as high as about 10 degrees above normal for late-May
by Tuesday. Long range models hinting at a ridge break down
starting around mid-week but at this time, have left forecast area
under mainly fair and dry conditions as it appears that Norcal
will remain generally under the influence of the upper ridge.
Mainly VFR conditions overnight and in the morning hours with
winds less than 10 kts. There is a chance LCL to areas of low
clouds could form in the valley by morning. MVFR to LCL IFR
conditions still likely over the mountains in scattered showers
and thunderstorms Wednesday afternoon.