Wednesday will bring the big warmup we have been talking about as daytime highs inland will rush upwards towards 100 degrees. Along the bayshore, 70s and 80s remain steady. Thursday will be the very hottest day of the forecast with temperatures well into the triple digits.

By noon, the weather service said temperatures in the hottest spots had risen to 94 in Livermore, and 93 in Antioch and Concord; those communities are generally the three hottest spots in the interior East Bay. In the South Bay, Morgan Hill was 94 and San Jose had reached 88.

Large portions of the Bay Area and the Central Coast were under a heat advisory Thursday morning, which has been extended for what could be the hottest days of the year.