Marine Weather and Tide Forecast for American Canyon, CA

DISCUSSION

Today and Monday

Current satellite continues to show the low stratus deck across the Central Valley and adjacent foothills. A few areas in the northern Sacramento Valley have gotten clouds to clear out and temperatures to warm. This is not the case for other areas within the Valley. This lingering stratus deck is thanks to ridge of high pressure over the eastern Pacific and southwestern CONUS.
Temperatures underneath the stratus have been well below normal, and areas above the stratus continue to be at or above normal.
This will continue into Monday as winds remain light and the upper level wave moving into the region slows and reaches CA by Tuesday. Look for continued low ceilings, mist, and foggy conditions through Monday. Fog may become dense overnight into Monday morning, with visibility reductions to a quarter mile or less for areas within the Central Valley.

Midweek

An upper level wave moves out of the eastern Pacific Monday night and into Tuesday increasing precipitation chances and breezy conditions to the region. Precipitation begins late Monday night and into early Tuesday morning for the Coastal Range and Shasta county area. Later, precip spreads east and south, but remains along and north of the I-80 area for Tuesday. Coverage will be isolated for the showers for much of Tuesday. By the afternoon, instability and moisture increase giving way to thunderstorm chances (10-25 percent) for areas north of I-80. Best chances will be within the Sierra, Sacramento Valley, and Coastal Range.
By Wednesday, coverage will be scattered to widespread across the entire forecast area for precipitation, with snow levels above 8000 feet. Thunderstorm chances will be 10-25 percent. A brief lull in precipitation Thursday morning and afternoon, before another round of precipitation moves into the region bringing breezier conditions.

Friday Onward

An active pattern continues for CA Friday and into next weekend, with another upper level wave moving out of the eastern Pacific.
This system has trended cooler over the past couple of runs of the NBM. Snow levels are looking to be above 7500 feet by Friday afternoon and evening and remaining so through the weekend.
Chances for widespread precipitation with the system as it moves through. Along with the precipitation, conditions will be breezy for the forecast area. Confidence remains low on the full development, track, and snow levels with the system.

AVIATION

Persistent low ceilings and reductions to visibility across the Valley and lower foothills through the TAF period. RDD and RBL have started to see some clearing, but this is expected to be brief before stratus redevelops this evening creating lower ceilings and visibility reductions. LIFR to IFR conditions are expected overnight and into Monday morning, with light and variable winds. Quarter mile or less visibilities for areas in the Sacramento Valley. Areas in SCK and MOD will see visibility reductions but down to half mile or less.

STO WATCHES/WARNINGS/ADVISORIES
None.