With the Labor Day weekend arriving in less than two weeks and with it the unofficial end of summer, the kind of heat that has gone mostly missing this year in the Bay Area seemed prepared to be blast the region.

Yet, even that heat is not expected to be as powerful as originally anticipated.

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“The heat is not going to be as severe as we thought it was going to be,” National Weather Service meteorologist Dylan Flynn said Monday. “It’s not going to be extreme like it initially appeared it would be.”

It sounds a bit like an appropriate turn for for a summer that has been mild in temperatures and absent of long-term heat waves.

This blast will send temperatures into the mid-to upper 90s on Wednesday in the hottest places and then to the upper 90s on Thursday. Some places such as Antioch in far east Contra Costa County, might creep past 100 degrees by a degree or two, Flynn said.

In the South Bay, the hottest day likely will be Friday, with Morgan Hill setting the pace at 97, up 2-3 degrees from Thursday.

Those temperatures — while hot to be sure — are down from original forecast high of 107 that the weather service thought may scorch the region’s hottest places.

That peak will last one day, with the hottest temperatures again reverting to the mid-90s on Friday and then into the upper 80s and low 90s on Saturday. In that sense, this latest blast will mirror other heat-ups this season that have not lasted longer than a day or two.

“The peak for most of the places is going to be Thursday, but it’s going to be warmer than the average on Friday, too,” Flynn said. “We’ll also get some light off-shore winds that we started seeing (Monday), and that trend will continue through the week.”

Those winds aim toward the Pacific Ocean instead of away from it and blow warm, adding slightly to the temperature hike but not adding much to any fire danger, Flynn said.

“The strength of the off-shore won’t be that high,” he said. “There’s still a pretty shallow marine layer that’s an influence. So the off-shore (winds) will be more of a temperature-thing than a fire-weather thing.”

The hike in the temperatures has been caused by a high-pressure ridge building over the southwestern desert. A similar pattern lifted temperatures earlier this month.

That ridge does not appear to be as long-lasting as forecasters originally thought it might be; thus, the lack of staying power for this heat blast. So it is that by Saturday, temperatures are expected to be heading back to the comfortable levels that have marked the 2025 summer.

“The weekend will be closer to what our average normally is this time of year,” Flynn said. “Then as we get into next week, it’s going to be very comfortable again.”