Twain Harte, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

116
FXUS66 KSTO 162022
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
122 PM PDT Mon Jun 16 2025

For additional details on weather and expected impacts over the
next 7 days, please visit weather.gov/sto/briefing.

.DISCUSSION...

.SYNOPSIS...
Dry weather this week with a warming trend into midweek and
Moderate HeatRisk in the Valley and foothills on Wednesday. Gusty
winds combined with low humidity will bring elevated fire weather
conditions late this week into the weekend.

&&

.KEY MESSAGES...

* Today-Wednesday:

 -Probability of Valley High Temperatures > 95F:
  --Northern/Central Sacramento Valley: 70-90% (85-100% on
   Wednesday)

  --Delta, S. Sac Valley, N. San Joaquin Valley: 40-80% (70-95% on
   Wednesday)

 - Above normal temperatures with areas of Moderate HeatRisk in
   the Valley and foothills by Wednesday as ridging develops.
   Potential for triple digit heat in the northern Sacramento
   Valley and Valley foothills(40-80% probability); mid to upper
   90s in other Valley locations.

 -Onshore flow expected to persist with periods of breezy winds,
  mainly in the afternoons and evenings and strongest across the
  Delta and vicinity. Breezy westerlies over the Sierra.

 -Low humidity may bring a brief period of elevated fire weather
  conditions across western portions of the northern San Joaquin
  Valley this afternoon with gusts up to 20-25 mph.

 -Warming and drying trend by mid-week may bring a brief period of
  elevated fire weather conditions, mainly across the northern
  Sacramento Valley.

*Thursday-Next Weekend:

 -Gradual cooling trend expected with stronger onshore flow
  Thursday-Friday. Strongest winds expected through the Delta and
  over the Sierra.

 -Periods of elevated fire weather conditions possible across the
  northern Sacramento Valley late this week due a combination of
  low humidity in the upper teens to low 20s with breezy winds.

 -Probability of wind gusts > 30 mph: 40-75% Saturday across the
  northern/central Sacramento Valley and Delta.

.Changes from previous forecast...
 -Lower chances for higher end Fire Weather Concerns as Min RHs
  have trended higher although breezy winds and dry conditions
  remain late week into the weekend.

&&

.AVIATION...

VFR conditions with mostly clear skies will continue at TAF sites
over the next 24 hours. Surface winds generally below 12 kts,
except in the vicinity of the Delta area, where there will be
sustained winds around 17 kts with gusts up to 25 kts through 06z
Tuesday.

&&

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

$$