An incessant and dangerous heat wave blistering Northern California was peaking Sunday with another round of record-breaking temperatures expected in the Bay Area and Sacramento Valley before gradual cooling begins.

Northern California's heat wave is expected to continue, with a Heat Advisory potentially extending into Monday and cooling predicted for mid-week.

Though the current heat wave peaked on Wednesday, the outlook going into the weekend doesn't bring much relief, according to the National Weather Service.

Some cities in Northern California are seeing temperatures in the upper 90s and lower 100s. Temperatures are generally in the mid-80s this time of year.