Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 290439
Area Forecast Discussion
National Weather Service Sacramento CA
939 PM PDT THU APR 28 2016
Breezy north winds today then again over the weekend, peaking
Saturday. Isolated showers and thunderstorms over the northern
Sierra today and through the weekend. Otherwise dry with above
normal temperatures through Sunday. Another wave drops down from
High pressure with clear skies this evening over Northern
California will give way to a low pressure area that will drop
into Nevada on Friday night. This will bring some clouds and
cooling to the area Friday with isolated showers possible over the
mountains late in the afternoon.
The center of the low will move into Western Nevada Friday night
and moisture wrapping around the low may bring some showers to the
Sierra Nevada. Snow levels look high above pass level until late
at night and Saturday morning. Windy conditions look to develop
in the valley on Saturday and then taper Saturday evening. The
mountains looks like they could see some decent northeast winds
Saturday night. Any lingering precipitation will be moving south
of the area by late morning.
On Sunday their is a weak wave that forms over Northern Nevada
on the northeast side of the low that will have moved to near the
four corners area. Winds will be much lighter but some additional
showers may occur over the Sierra near the crest. There may be
enough instability on Sunday for some thunderstorms to develop
over the Sierra Nevada.
.EXTENDED DISCUSSION (Monday THROUGH Thursday)
Sunday`s Rex Block near the Four-Corners is forecast to break down
by Mon...with upper ridging building over Norcal. Steering flow
forecast to become SWly which should preclude precip or any thunder
chances in our CWA...while there is a chance E of the Sierra Crest
along the deformation zone extending Wwd across the Great Basin.
Warmer than normal max temps continue Mon/Tue...then a cooling trend
with unsettled/showery weather developing for the middle of the week.
Synoptic cooling from the digging offshore trof and increasing onshore
flow will cool max temps to several degrees below normal Wed/Thu.
Although there are model differences...synoptic pattern suggests
chance of showers increases Wed/Thu as cyclonic flow increases
over Norcal with possible T-storms over the coastal range Thu. JHM
VFR conditions for TAF sites thru Fri. North to Northwesterly
winds at TAF sites with gusts up to 25 kts. Winds less than 10
kts overnight into Friday. Winds will transition Friday afternoon
becoming more West to Southwesterly with locally breezy conditions
possible in the afternoon. JBB