The week-long heat wave in the Bay Area is starting to temper by a few degrees on Thursday but will still remain in the 90s in most places, according to a National Weather Service meteorologist.
It will be four to five degrees cooler on average, but the difference may still be be difficult to fee as it will still be really warm Thursday, NWS meteorologist Rachel Kennedy said.
Most of Santa Clara County will see temperatures in the upper 90s, with San Jose on the watch to see if it will break its previous record for hottest temperature on this day. The “Capital of Silicon Valley” was forecast to reach 98 degrees today; the previous record was set at 97 in 1985. South county cities are expected to reach the low 100s, with Morgan Hill expected to reach a high of 104.
Along the East Bay, temperatures are expected to warm as elevation increases, due to dwindling influence from the San Francisco Bay shore, Kennedy said. Areas along the coastline are expected to reach the upper 80s and mid 90s. Oakland was forecast to reach high of 88, making it slightly cooler Thursday than Wednesday due to the bay’s influence. Berkeley was expected to peak at 86.
Closer inland, most cities might see high temperatures in the low 100s. Livermore was on the watch to see if it might break or come close to its previous record-high temperature on this day of 106 in 1980; temperatures were expected to peak at 103 in the East Bay city. Kennedy said Brentwood and Concord had an excessive heat warning in place until 11 p.m. on Friday, with the former expected to reach 104 degrees while the latter was forecast to hit 103. Pleasanton was forecast to reach 104, Walnut Creek was expected to peak at 103 and Lafayette was predicted to reach 102 degrees.
The San Francisco peninsula area was expected to cool down Thursday, with the excessive heat warning in San Francisco transitioning to a heat advisory. However, Kennedy said inland areas of the peninsula still are under an excessive heat warning. Redwood City was forecast to reach a high of 97. The western coast close to the ocean is also expected to cool down a bit and temperatures were expected range from the 70s to low 80s.
Most areas of the Bay Area are under an excessive heat warning until 11 p.m. Friday, except North Bay. Kentfield in Marin County was expected to peak at 97, just a couple degrees short of a record-setting high of 99 in 2012.
The heat wave is being caused by a ridge of high pressure over the Bay Area, causing heat to build, Kennedy said. Nothing is really forcing the front to move out, but over the weekend, an upper level low pressure system was forecast to develop over off the shore. It was forecast to be making it’s way inland on Monday, and cooler weather is expected to wash over the Bay Area on Monday and Tuesday next week.