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000 FXUS66 KSTO 061858 AFDSTO Area Forecast Discussion National Weather Service Sacramento CA 1158 AM PDT Sat Jun 6 2026For additional details on weather and expected impacts over the next 7 days, please visit weather.gov/sto/briefing.KEY MESSAGES
-Cooler, near normal temperatures start today, and drop below normal early next week.
-Breezy afternoon and evening onshore winds today, becoming northerly overnight into Sunday, with low humidity bringing a few areas of brief elevated fire conditions.
-Mostly dry weather for the next week, except for slight chances of light mountain showers Monday and Tuesday.
-Potential increase of gusty north winds, areas of low humidity, and above normal temperatures by late next week.
DISCUSSION
Main change to the forecast continues to be decreasing rainfall amounts for early next week
..Today and Sunday
An approaching system brings cooler, near normal temperatures through the weekend, with mid to upper 80s expected in the Valley, Delta, and lower foothills. Daytime humidities remain low, primarily in the teens to low 20s (though areas in the northern Sacramento Valley may dip down into single digits on Sunday). This, in combination with gusty winds will bring a few intermittent hours of elevated fire weather concerns in the northern Sacramento Valley. On Sunday, strongest winds will occur overnight into the early morning, tempering some of the risk for elevated fire weather concerns since they do not coincide with minimum daytime humidities.
..Monday and Tuesday
A secondary trough will move in behind the first early next week. The primary impacts expected from this system at this point are below normal maximum daytime temperatures (low to mid 80s for the Valley) and increased daytime relative humidities. There is still a slight chance (15 to 40%, highest near Lassen National Park) for a quarter inch of rain or more in the mountains and portions of Shasta County, but chances continue to diminish as we get closer to the early parts of next week.
..Wednesday through Friday
Northerly winds increase as the early-week trough shifts into the Great Basin. Gusty winds and low humidity will bring increased fire weather concerns across the Valley, Delta, and lower foothills, especially Thursday and Friday. Temperatures trend higher late in the week, with hints of mid 90s to potential triple digit highs in the Valley by the weekend.
AVIATION
VFR conditions over the next 24 hours. Northwest surface wind gusts 15 to 23 kts in the northern San Joaquin Valley until 05Z Sunday and in the northern Sac Valley through 19Z Sunday. West to south winds sustained 10 to 15 kts with gusts to 20 kts in the southern Sac Valley and gusts up to 25 kts in the Delta vicinity through 18Z Sunday.
STO WATCHES / WARNINGS / ADVISORIES
None.