Area Forecast Discussion
Issued by NWS Sacramento, CA
FXUS66 KSTO 271701
Area Forecast Discussion
National Weather Service Sacramento CA
1001 AM PDT WED APR 27 2016
Scattered showers and thunderstorms today. Light snow
accumulations over the higher elevations of the NorCal mountains.
A little breezy behind this system on Thursday, then dry and
An upper level level trough with a surface cold front will
quickly pass through Northern California today. Cool air aloft
with this system will bring unstable conditions with scattered
showers and afternoon thunderstorms. Radar and surface
observations show scattered showers currently along the western
side of the Sacramento Valley pushing eastward. By noon there will
be the potential for showers across the forecast area.
Latest model soundings are showing significant CAPE this afternoon from
the northern Coastal Range and to the southeast through the
southern Sacramento and northern San Joaquin valleys and extending
into the Sierra. This area has the best potential for
thunderstorms, though shear looks like it will fairly limited.
This reduces the potential for stronger, rotating thunderstorms.
Most storms are expected to be more of the relatively short-lived
pulse type. The main concerns are small to moderate size hail and
locally heavy rain. With relatively dry low levels, local gusty
winds near storms could also be an issue. The most favorable
timing for thunderstorms looks like 2-5 pm. Convection over the
Valley will diminish after sunset, with some lingering showers in
Snow showers in the higher mountains could bring a few inches of
wet snow late this afternoon into tonight. Travelers over mountain
passes should use caution. EK
.EXTENDED DISCUSSION (Sunday THROUGH Wednesday)
A ridge of high pressure will dominate the long term forecast
period with warm temperatures and quiet weather. The strongest
portion of the high pressure system will be Sunday and Monday,
which as a result, will bring above normal temperatures to the
region. The Valley could see temperatures in the mid to upper 80s,
which would be 10 to 15 degrees above normal for this time of
A higher amplitude trough of low pressure will slide down into the
eastern Pacific just off shore of California Monday and Tuesday.
High temperatures will cool slightly, but ranges will still be
around 5 degrees above normal. Some slight chances for showers are
possible along the Coastal Range, but otherwise no significant
weather or precipitation is expected during the long term period.
VFR conditions are expected at the terminals for the next 24
Winds will be light out of the south and will generally shift to
the west or northwest direction Wednesday night after an upper
level disturbance moves through the NorCal region. There could be
a few wind gusts during the afternoon hours, mainly for the
Stockton terminal. Showers and isolated thunderstorms are
possible with the vicinity of the terminals, but confidence of
direct influence is lessening at this point with short term model
guidance keeping the Valley mostly dry.