Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 121600
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
900 AM PDT Sat Apr 12 2014
A weak system will bring a slight chance of showers and
thunderstorms over the Southern Sierra this afternoon. High
pressure and well above normal temperatures dominate into early
next week, followed by a series of weak troughs that move through
northern California by the middle of next week.
.Short Term Discussion (Today through Monday)...
A good delta breeze overnight brought a few low clouds into the
interior this morning. The low pressure area has moved out of
California and into Arizona and models indicate much less activity
over the Southern Sierra today than compared to yesterday and
activity staying south of our CWA. To the north a weak wave will
be result in a north to northwest flow aloft over the area which
will not be good for thunderstorm development over the Northern
Sierra. Temperatures around Sacramento may only get up into the
lower 70s today to around 80 at Redding.
Northerly winds on Sunday will help to warm temperatures back into
the upper 70s to lower 80s for the interior valley. The delta
breeze is expected to weaken after this evening and winds
eventually turning north Sunday morning in the delta.
.Extended Discussion (Wednesday through Saturday)
Dry northwesterly flow aloft sets up over NorCal Wed/Thur on the
backside of an upper-low digging over the Rocky Mountain states.
The GFS is much more vigorous with the low than the EC, but
either way it will much to far to our east to do much other than
cool temps a bit and bring some dry north winds if the GFS
solution is correct. Model disparity is readily apparent in the
high temperature forecast for Wednesday in the Sac area, where
the raw GFS is > 10F cooler than the raw EC. Current forecast
splits the difference with model consensus.
A Pacific trough is progged to approach the far Northern CA
coastline by the weekend, though model confidence metrics show
little predictability in this feature. Have thus kept near climo
pops for now for areas north of I-80 (which translates to a
chance of showers for the mountains with little to no chance in
the Valley). -DVC
VFR next 24 hours for Interior NorCal TAF sites as an upper low
drifts by to the south with little impact on area weather. Few
isolated showers/thunderstorms over Southern Sierra this
afternoon. Generally light winds around 10 knots or less, except
SW 15-25 knots in the Delta area, and up to 15 kts for airports in
the near vicinity including KSMF and KSAC. -DVC