Area Forecast Discussion
Issued by NWS Sacramento, CA

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000
FXUS66 KSTO 100945
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
245 AM PDT Sat Apr 10 2021


.SYNOPSIS...
Continued dry and warm conditions are forecast to prevail through
the weekend and into next week. Periods of breezy conditions are
expected tomorrow, as well as early next week.

&&

.DISCUSSION...
Infrared satellite imagery reveals clear skies over interior
northern California this early Saturday morning while marine
stratus blankets the coast and portions of the Bay Area. Fort Ord
profiler near Monterey indicates the marine layer is just north of
2,000 ft deep, and combined with healthy onshore flow (SFO to SAC
surface pressure gradient at +3.0 mb, and decreasing) can`t rule
out some stratus pushing into the Delta by sunrise Saturday. HREF
is rather bullish with painting rather high probabilities of
ceilings making inland as far as the Sacramento area, but due to
the dry airmass, think any stratus in the Valley would be patchy
at most.

Dry, northwest flow aloft with upper level ridging just west of
the California coast will support continued above-normal
temperatures again for the region on Saturday afternoon. Valley
highs will max out in the upper 70s to low 80s, or about 5 to 10
deg F above early April normals.

Surface high pressure will build in Oregon on Sunday, promoting
the development of north-to-south surface pressure gradients over
northern California. This will result in increased northerly winds
across portions of the area on Sunday, particularly in the
northern Sacramento Valley, as well as the wind-prone westside of
the Valley (generally along and west of the I-5). Peak winds gusts
will generally be in the 20 to 30 mph range, but can`t rule out
some isolated higher gusts.

Shortwave through will drop south from the Pacific Northwest
around Tuesday-Wednesday next week. While there remains some
uncertainty with respect to the timing and placement, this type of
synoptic setup would expect favor increased north / east winds
for northern California, as well as a slight chance for mountain
showers. The National Blend of Models presently gives the Sierra
about a 10 to 20 percent chance of precipitation during this
period.

While it is only April, will note that wildland fuels are
significantly drier compared to climatology. The Energy Release
Components (ERCs) for the Sacramento Valley/Foothills is near-
record level for this time of year. The absence of precipitation
along with dry winds will allow fuels to continue to dry out over
the coming days. // Rowe

&&

.EXTENDED DISCUSSION (Wednesday THROUGH Saturday)...
Large upper low centered in the Great Basin Wednesday with
embedded vort lobes rotating through the CWA. Moisture looks
limited, however enough dynamics to support a threat of showers
over the higher terrain of Western Plumas and northern Sierra
Nevada. Some breezy north to east continues into Wednesday
morning.

Models diverge with handling of this feature late next week into
the weekend. Main message is low elongates W-E Thursday into
Friday as it slowly fills, with placement of the low varying.
Short wave trough progged across northern portions of the CWA
late Friday into Saturday where some light showers may occur over
the Shasta and Western Plumas mountains. Slow warming trend with above
normal high temperatures expected through the extended forecast
period.

&&

.AVIATION...
VFR conds ovr intr NorCal nxt 24 hrs. Vcnty of Delta, sfc wnd
gsts to 25 kts poss attm, otrw sfc wnds genly AOB 12 kts.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$


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