Marine Weather and Tide Forecast for American Canyon, CA

Discussion
Current GOES-West visible satellite imagery shows clear skies and abundant sunshine being observed across interior northern California on this Thursday afternoon. Temperature observations are currently in the 90s to around 100 in the Valley and lower foothills, with 70s to low 90s in the upper foothills and mountains, valid at 2 PM PDT.

Unseasonably hot temperatures continue today and over the next several days across the area, with widespread Moderate to Major HeatRisk in the Valley, Delta, and foothills, especially from Interstate 80 southward. HeatRisk has trended higher over the weekend, and the Heat Advisory has been extended through Saturday evening at 11 PM PDT for the southern Sacramento Valley, Delta area, northern San Joaquin Valley and Motherlode. High temperatures will be trending around 15 degrees above normal for early October climatology. Forecast highs are expected to be in the 90s to around 101 degrees in the Valley through Sunday.

A shortwave moves across the region on Friday, bringing along increased westerly winds mainly to the higher terrain and ridges of the Coast Range, northern mountains, Sierra and into the Burney Basin. Dry conditions with low relative humidity, combined with the increased winds will lead to elevated fire weather conditions over the aforementioned locations on Friday. Increased mid level clouds are also expected across interior NorCal with this shortwave on Friday.

.EXTENDED DISCUSSION (Monday THROUGH Thursday)...
Temperatures will be slightly cooler but still above-normal Monday into Tuesday, as weak upper-level troughing moves through the area. This synoptic feature will result in increased onshore flow through the Delta, with the NBM indicating gusts 15 to 20 mph in the afternoon and evening hours. Otherwise, light periods of northerly winds are expected through the northern half of the Sacramento Valley. Ensembles and clusters are in good agreement that additional cooling is expected by mid week, bringing more seasonable temperatures, breezy onshore flow, and continued dry weather.

AVIATION
VFR conditions over interior Northern California for the next 24 hours. Surface winds are expected to remain below 12 knots except locally southwesterly direction surface wind up to 20 knots gusting up to 30 knots in foothills/mountains after Friday 08z.

STO WATCHES/WARNINGS/ADVISORIES
Heat Advisory until 11 PM PDT Saturday for Carquinez Strait and Delta-Motherlode-Northern San Joaquin Valley-Southern Sacramento Valley.