Marine Weather and Tide Forecast for Port Costa, CA

DISCUSSION

Warm and dry conditions expected today into Wednesday as ridging remains in control of the large scale pattern over the area. Above normal temperatures will rule with 90s to low 100s across the Valley. This will lead to minor to moderate HeatRisk but no concerns for heat headlines. Delta Breeze will continue to bring evening relief thru the Delta into the Sacramento area. Min RHs will be in the teens to low 20s but wind will remain below RFW criteria. Wednesday afternoon will see a nonzero chance of a mountain shower across the northern Shasta County border but current models keep any developed system north of our area, tracking eastward.

Thursday is a transition day as cooling trend begins and continues into the weekend. A deep trough from the Gulf of Alaska will slowly dig into the Pacific Northwest Friday into the weekend and gradually move east into the Great Basin. This will serve to increase onshore flow for our area Friday into Saturday with breezy southerly winds across the area. This will bring a bit of moisture with it with the chance for a few showers across far northern portions of the area and southern Cascades. At this time, does not look like a big signal for convective activity but will keep an eye on trends. Current precipitation depict a glancing blow for our area over the mountains Friday afternoon into Saturday with still minimal precipitation impacts.

As trough departs, pressure gradient strengthens, leading to the potential for a north wind event Sunday into Monday. Still some uncertainty in ensemble solutions with timing and strength of the trough but will need to monitor for the need for any fire weather headlines as we get closer to the weekend.

AVIATION

VFR conditions are expected to continue through the TAF period.
Winds 6 to 12 kts in the Valley into 06z Wednesday before becoming light and variable overnight outside of winds through the Delta to the Sacramento sites which will gusts up to 15-25 kts until 12z Wednesday but linger in the Delta.

STO WATCHES/WARNINGS/ADVISORIES
None.