Heavy Snow and Hail in California, April 23 to 25, 2015

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SACRAMENTO CA
205 PM PDT Thu Apr 23 2015

.Synopsis...
Showers and thunderstorms possible this evening...mainly in the
higher terrain. Can't rule out a roll of thunder though in the
valley mainly through midnight. A fast moving wet system pushes
across the area Friday Night and Saturday morning for a nice shot
of moisture.

&&

.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
conditions. Rasch
&&

.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.

&&

.Aviation...

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.

&&

.STO Watches/Warnings/Advisories...
None.
&&

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE SACRAMENTO CA
232 PM PDT THU APR 23 2015

CAZ017-064-232215-
CLEAR LAKE/SOUTHERN LAKE COUNTY CA-SOUTHERN SACRAMENTO VALLEY CA-
232 PM PDT THU APR 23 2015

THE NATIONAL WEATHER SERVICE IN SACRAMENTO HAS ISSUED A

SIGNIFICANT WEATHER ADVISORY FOR...
  NORTHWESTERN YOLO COUNTY IN CENTRAL CALIFORNIA
  EXTREME SOUTHEASTERN LAKE COUNTY IN NORTHERN CALIFORNIA

UNTIL 315 PM PDT

AT 230 PM PDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
STRONG THUNDERSTORM 5 MILES WEST OF RUMSEY..MOVING SOUTHEAST AT 5
MPH.

HAIL UP TO THE SIZE OF PENNIES AND WIND GUSTS UP TO 40 MPH ARE
EXPECTED WITH THIS STORM...ALONG WITH HEAVY RAIN AND FREQUENT
DANGEROUS LIGHTNING.

THIS STORM MAY INTENSIFY...SO BE CERTAIN TO MONITOR LOCAL RADIO AND
TV STATIONS...AS WELL AS LOCAL CABLE TV OUTLETS...FOR ADDITIONAL
INFORMATION AND POSSIBLE WARNINGS FROM THE NATIONAL WEATHER SERVICE.

LAT...LON 3892 12240 3892 12219 3876 12223 3878 12227
      3883 12230 3883 12239 3884 12241 3890 12241
TIME...MOT...LOC 2132Z 309DEG 3KT 3888 12234

CS