Marine Weather and Tide Forecast for Fairfield, CA

DISCUSSION
Temperatures have trended even higher today (1-4 degrees at noon), and are well above normal. The big change is that winds are generally much lighter than yesterday, though there are still some northerly gusts up to 20 mph through the morning for the northern Sacramento Valley. Humidity levels this afternoon are generally 4 to 8 percent higher, 8 to 10 percent in the Delta, so along with the lighter winds fire concerns are elevated but generally not critical. Low humidity levels and periods of breezy onshore winds will continue into next week. Onshore flow, increasing humidity and cooling temperatures are expected mid to late week, further lessening fire weather concerns.

Triple digit Valley highs are expected this afternoon and continue through at least the early weekend in many locations.
Widespread Moderate HeatRisk is present this afternoon, with areas of Major HeatRisk, mainly for the northern Sacramento Valley and adjacent foothills. Delta breeze influenced locations will see some cooling through the weekend, while the northern Sacramento Valley, mountains, and foothills are forecast to see just slightly lower highs. The Heat Advisory continues for the northern and central Sacramento Valley and adjacent foothills through 11 pm Saturday, June 13th. While other areas in the Valley will benefit from the Delta breeze cooling influence, especially in the evening, it remains important for everyone in interior NorCal to practice heat safety! Stay cool and hydrated, and consider checking in on those more sensitive to heat.

Early next week high temperatures have trended even higher for the northern and central Sacramento Valley, and could see even higher temperatures than for late this week, up to 110 in some northern Sacramento Valley locations. Probability of Major HeatRisk has continued to trend larger there, around 100 percent in some spots, so confidence is high. An Extreme Heat Warning has been issued for the northern Sacramento Valley, adjacent mountains and foothills, and Butte County from 11 am Sunday to 11 pm Tuesday. Temperatures are forecast to trend lower mid to late week, back to near normal Thursday.

Mainly dry weather is expected into next week. Still can't completely rule out a few stray showers or an isolated thunderstorm over the Sierra crest south of US HWY 50 over the weekend into Monday.


AVIATION

VFR conditions with clear skies over the next 24 hours. Winds generally less than 12 kts everywhere this afternoon, except in the vicinity of the Delta, where westerly gusts up to 25 kts remain until around 12z Saturday.

STO WATCHES/WARNINGS/ADVISORIES
Heat Advisory until 11 PM PDT Saturday for Butte County Below 1000 ft-Central Colusa County Incl. I-5-Central Glenn Co & Interstate 5-Eastern Colusa County-Eastern Glenn County-N. Sac Valley in Tehama County-Shasta Metro-Sierra (Tehama-Plumas) 1000- 3000 ft-Sutter/Yuba counties below 1000 ft-W Tehama Co Foothills 1000-3000 ft-W. Glenn/Colusa Foothills 1000-3000 ft-W. Shasta County 1000-3000 ft.
Extreme Heat Warning 11 AM PDT Sunday to 11 PM Tuesday PDT for the northern Sacramento Valley, surrounding mountains and foothills, and Butte County.