A dome of hot air will move over the Bay Area Wednesday to bring plenty of 90s and a few isolated 100s. However, onshore winds at the Coast will bring much colder weather. Details on if you need a jacket or shorts in my full forecast.
Wednesday afternoon will be a good time for Livermore residents to fire up their air conditioners as temperatures are expected to climb near record highs.
Livermore could hit 107 degrees, according to the National Weather Service forecast, which would be the city’s hottest day since it reached 109 on June 28, 2009.
It’s not quite record heat, but close. The hottest recorded July day in history came on July 7,1905, when temperatures reached 113 degrees, according to the National Weather Service. The highest temperature ever recorded on July 11 was 111 in 1961.
For the burgeoning wine region, the triple-digit heat is not a welcome presence. It could force grapes to ripen too quickly, which would result in wine with an elevated alcohol content and not enough acid. If the heat sticks around for an extended period of time, it could force winemakers to harvest earlier than they might have otherwise.
Tom Heineman, co-owner of Bent Creek Winery in Livermore, said for now things are OK because at least the nights have been cool. "Fortunately in the Bay Area, we have cool evenings," he said.
If the heat continues, he said, that would be cause for concern. Right now, he's closely monitoring his grapes and making sure they are irrigated.
Watch Kim Tere's full report at 5 p.m and 6 p.m.