Big River, California 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

946
FXUS66 KSTO 102135
AFDSTO

Area Forecast Discussion
National Weather Service Sacramento CA
235 PM PDT Thu Jul 10 2025

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


.DISCUSSION...

.SYNOPSIS...
Hot weather is expected through Monday with Moderate to locally
Major HeatRisk. Some Delta breeze influence will bring minor
cooling over the weekend and into next week in the Delta and
adjacent Valley locations. Dry and periodically breezy northerly
winds are expected through Friday, with breezy onshore winds next
at times next week.

&&

.KEY MESSAGES...

*  Today-Friday:
 - Upper level high pressure ridge continues to build, resulting
   in dry conditions and warming temperatures
 - Widespread Moderate HeatRisk with areas of Major HeatRisk across
   interior NorCal
 - Smoke will continue to impact areas in the vicinity of the
   Green Fire, with northerly winds spreading smoke and haze
   southward through the Valley into Friday
 - Locally breezy northerly flow in the northern/central
   Sacramento Valley and adjacent terrain, mainly in the overnight
   through morning timeframe
 - Low daytime relative humidity with moderate to poor overnight
   recoveries over foothills and mountains

*  Saturday-Monday:
 - Continued hot and dry conditions, with widespread Moderate
   HeatRisk and areas of Major HeatRisk in the forecast for
   interior NorCal into early next week
 - There will be some Delta breeze influence over the weekend and
   into next week that will allow for minor cooling in the Delta
   vicinity
 - Upper level ridging looks to continue to be the dominating
   weather pattern into next week

* Tuesday
 - Cooling trend begins with Minor to Moderate HeatRisk

.Changes from previous forecast...
 - Temperatures and HeatRisk have trended higher for Monday
 - The Heat Advisory north of Interstate 80 in the Valley,
   foothills and mountains beginning Friday at 11 am PDT has been
   extended and now continues through Monday evening 11 pm PDT.

   &&

.AVIATION...
VFR conditions across interior NorCal next 24 hours. Periods of
breezy onshore winds with gusts up to 15 to 20 knots in the Delta
vicinity through 12z Friday. Elsewhere, sustained speeds generally
less than 12 knots over the next 24 hours, with gusts less than
15 kts. Local MVFR conditions possible at times in HZ/FU vicinity
of Shasta County wildfire, including KRDD.

&&

.STO WATCHES/WARNINGS/ADVISORIES...
Heat Advisory from 11 AM Friday to 11 PM PDT Monday for Burney
Basin / Eastern Shasta County-Central Sacramento Valley-
Mountains Southwestern Shasta County to Western Colusa County-
Northeast Foothills/Sacramento Valley-Northern Sacramento Valley-
Shasta Lake Area / Northern Shasta County-Western Plumas
County/Lassen Park.

&&

$$