Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 271134
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
334 AM PST Thu Nov 27 2014
Mild Thanksgiving will give way to a wet Friday night and
Saturday. Impacts with this first system not looking too bad but
should be limited to elevations above 6000 feet where from 6 to 12
inches of snow is possible late Friday into Sunday morning.
Unfortunately a lot of uncertainty remains with second storm
system arriving sometime in the Monday through Wednesday time
.Discussion...(Today through Sunday Night) First weather system will
move into northern portions of the Valley Friday late afternoon
then push southward to Sacramento area early morning
Saturday..then linger around with some weak upward motion and
moisture through Saturday night. Parallel GFS continues to be
wetter with this system compared to operational GFS. SREF mean and
NAM also coming in wetter than operational GFS. With this in mind
tweaked up QPF values only slightly across the area during this
time. Snow levels will be tricky Saturday but should start around
5,000 feet and rise to around 6,000 feet than back down to around
5,000 feet by Sunday morning. Amounts enough to cause some impacts
but will likely be limited to elevations above 6,000 feet. Amounts
look to be low enough to continue to hold off on any highlights.
Sunday through Sunday night is another tricky period. GFS swings more
moisture and energy up into are for another round of precipitation.
Have kept pops pretty much the same in the 60 and greater area.
Snow levels should remain fairly high at or above 6,000 feet for
again minimal amounts and impacts. ECMWF at this time has more
ridging in the area but keeps some moisture and lift to produce
precipitation so overall looks like a cloudy and wet at times day.
.Extended Discussion (Monday through Thursday)
As noted from day shift yesterday...confidence unfortunately
decreasing with next system originally thought to be stronger of
these 2 systems. This still may be the case as it seems likely
upper low will eventually shift into CA but timing of that system
to arrive continues to be troublesome. GFS is more is deeper and
further east with the upper low Monday afternoon and night brining
miosture into northern valley with ECMWF also unsettled but with
different solution keeping upper low further west.
Tuesday and Tuesday night...GFS moves the upper low to the coast
and into central CA which would bring some nice moisture to the area
(with parallel even wetter again)...with ECMWF again further west
delaying the arrival of it until Wednesday and Wednesday night. At
this time seems best message is that we should get another round
of rain...but when is unsure at this time. Either scenario though
doesn`t look to be much of an impact. Rasch
BKN-OVC high clouds today. Patchy IFR/LIFR fog will persist
through about 18z today across portions of the Central Valley,
otherwise VFR conditions with generally light winds expected
across TAF sites.