Hot and dry weather through the weekend. Temperatures will peak on today and Saturday with areas of Major Heat Risk. Heat Advisory in effect 11 AM Friday until 11 PM Saturday. Dry fuels and very low humidity may lead to easier fire starts. Areas of breezy southwest winds in the afternoon and evening. Not as hot next week.

Major Risk for heat-related illnesses for pets, livestock, and much of the population, especially anyone without effective cooling and/or adequate hydration. Impacts likely in some health systems, heat-sensitive industries and infrastructure. Today: 10-40% chance of exceeding 110° F in the Central/Southern Sacramento Valley, 40-75% chance in the northern Sacramento Valley. Saturday: 20-55% chance of exceeding 110° F in the northern Sacramento Valley

Discussion

Skies were clear early this morning. The marine layer is being suppressed by strengthening high pressure over the region (profilers show the depth has lowered below 1k ft). Onshore surface pressure gradient continues to wane, though a weak Delta Breeze persists at Travis AFB with southwesterly winds around 20 mph.

Current temperatures are milder compared to 24 hours ago with most locations running about 2-6 degrees warmer. At the lower elevations, readings range from the mid 60s in the Delta to around 80 in some spots across the northern Sacramento Valley.

Heat will continue to build over NorCal, peaking today and Saturday, as high pressure builds up from the southeast. Hottest readings are expected in the northern Sacramento Valley this afternoon as light to moderate northerly breezes enhance warming. Highs in Redding and Red Bluff are expected to top out around 110-113 degrees.

Maximum temperatures will once again be in the triple digits.

Elsewhere, most of the Central Valley will see highs from 105-110.

Overnight lows will also be warm across the valley tonight and Saturday night with lows only in the mid 60s to around 80.

The result will be widespread moderate heat risk with areas of major heat risk. A Heat Advisory will be in effect from 11 AM today to 11 PM Saturday.

A modest cooling trend is forecast to begin Sunday as trough over the Gulf of Alaska approaches and brings a return to stronger onshore flow.

Breezy southwest winds are possible Sunday evening through the Delta and over higher terrain, especially the northern Sierra.

Fire weather concerns this weekend. Hot temperatures along with low daytime humidity will lead to increased fire weather conditions. Moderate to poor overnight recoveries in the foothills.

Hot temperatures may cause heat related illnesses, especially for those spending prolonged periods outside during the hottest part of the day. People should continue to practice heat safety, especially during the Friday through Saturday time-frame where temperatures will be the hottest.

Additionally, rivers are still running fast and cold across portions of interior NorCal, and people should wear a life jacket and be cautious around waterways!

Extended Discussion (Tuesday through Friday)

Interior NorCal sandwiched between upper troughing to the NW and upper high over Desert SW through the extended forecast period. Dry weather will result with high temperatures near to slightly below normal.

Locally gusty wind at times, mainly near the Delta and over higher terrain.