Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 240544
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
1044 PM PDT Thu Apr 23 2015
Showers and thunderstorms possible overnight in the higher
terrain. A fast moving wet system pushes across the area Friday
Night and Saturday morning for a nice shot of moisture.
Update 1045 pm...
Trough dropping south and outflow boundaries from earlier
convection have been enough to initiate shower and thunderstorm
development farther south including the northern Sac metro area.
Have reintroduced precip chances for the valleys through 4 am as a
Disturbance dropping southeast has enhanced showers and
thunderstorms this evening with hail up to pennies possible.
Strongest activity will be over the Sierra and diminish after
3am. Have updated forecast to place the emphasis of precip chances
over this area. Rainfall amounts up to 0.50 inches will be
possible with the strongest storms. Dry weather will prevail in
the valley overnight and have removed chances Redding to
.Previous Discussion (Today through Sunday)...
Some activity starting to fire early this afternoon up along the
coastal range and also south of I-80. Don`t expect activity to be
as strong as yesterday given less upper forcing. However...a weak
wave does push across the area later this evening and overnight
which will bring a chance of convection to the valley up to around
midnight. This is covered well in the current forecast.
Emphasis then shifts to the next strong system which pushes across
the area Friday night and Saturday morning. This isn`t a
particularly strong system...but will be in a good location for
our area to pick up a shot of valley rain and mountain snow. Will
be nice area of large scale ascent with placement of the low.
Expect a nice line of precipitation and snowfall rates may be
around 2" an hour early Saturday morning. This will likely cause
some traffic issues so we have issued a partner email to highlight
this. A highlight...maybe a snow advisory may be needed tomorrow
to further highlight the event.
Sunday...ridging does build back into the area for warming and dry
.Extended Discussion (Monday through Thursday)
High amplitude upper ridging modeled to move through Interior
NorCal Monday into early Tuesday of next week resulting in dry
weather with well above normal temperatures. Upper 80s expected
for high temps in the Central Valley with lower 90s possible in
the Northern Sacramento Valley Monday. Short wave trough pushes
into the PacNW late Wed into Thur bringing some synoptic cooling
with increasing onshore flow. Main threat of precip looks to
remain north of the forecast area attm.
Mnly VFR conds ovr Intr NorCal thru Fri aftn exc lcl MVFR conds poss
til arnd 06z Fri in mtn shwrs/tstms with isold shwrs/tstms poss
in Cntrl Vly this eve. Lcl SWly sfc wnd gsts to 25 kts poss in
Delta tngt with areas Wly sfc wnd gsts to 30 kts poss ovr hyr trrn
erly this eve and agn Fri aftn/eve.