Northern CA Forecast Discussion
FXUS66 KSTO 012132
Area Forecast Discussion
National Weather Service Sacramento CA
232 PM PDT Sun Aug 1 2021
Dry weather with near-normal temperatures expected through the
week with dry conditions prevailing. Breezy onshore winds at
The area remains sandwiched between an eastern Pacific trough and
ridging centered over the 4-Corners area. Temperatures started a
few degrees cooler this morning, but are currently about the same
as this time yesterday. Highs this afternoon should be pretty
typical for the start of August. For the Valley, this means around
100 for the northern Sacramento Valley and mid to upper 90s
elsewhere in the Valley, mid 80s to low 90s in the Delta and
Skies have been mostly clear except over the Sierra and southern
Cascades, where some afternoon cumulus have developed. So far
convection has remained east of the crest as expected.
Thunderstorm and show activity should continue to track eastward
away from the area this evening. This looks like the end of the
monsoonal thunderstorm threat for a while, with dry weather even
for the mountains through the rest of this week.
Southwest flow aloft over the area will continue persistent
onshore flow for much of the forecast period with occasional
breezy conditions developing in the afternoons and evenings around
the Delta and portions of the Sacramento and San Joaquin Valleys.
This will bring general near-normal temperatures this week.
Highest temperatures are expected on Tuesday, peaking at around
104 over the northern Sacramento Valley, 99 for the southern
Sacramento Valley. Some cooling is expected for mid week as the
Pacific trough moves onshore Wednesday.
The trough moving onshore will bring some breezy onshore winds.
This could bring some fire weather concerns, though lowest
humidity levels are expected earlier, on Tuesday. The onshore
flow will bring some increasing humidity when winds are breeziest,
late Wednesday afternoon and evening. Winds could gust to 20 to 30
mph over ridges.
(Thursday THROUGH Sunday)
Most ensembles and cluster solutions bring the trough along the
130W meridian onshore near the California-Oregon border on
Thursday. This solution would bring continued onshore flow to the
region, near-normal temperatures, and dry conditions into next