It's going to be quite hot all over the Bay today, with thermometers hitting 90 degrees and above in multiple spots. But the National Weather Service notes that this may not be a record-breaker of a day for most locales, because the records around here for April 7 are pretty high.

San Francisco should see temps in the 80s today, and if you're in Napa, Sonoma, or Walnut Creek, you're looking at 90 and above. Santa Clara Valley may see a high of 95. These numbers are 15 to 25 degrees above normal for this time of year, but that's not to say they've never happened.

"It should be noted that a similar heat wave occurred in early April back in 1989 and many of those records may still stand," the National Weather Service said in a statement, per KPIX. “Therefore, it is uncertain how many records may or may not be broken."

The record for April 7 in downtown San Francisco is 92 degrees, set in 1989. In Redwood City it hit 90, and in Gilroy it was 96 on that day. The next highest-degree record for April 7 in SF was 81 degrees, and that was set 50 years earlier in 1939 — so today may edge in to second place behind 1989, at least in SF.

That's not to say some records may be broken, but we'll see.

Daniel Swain of Weather West says this mini heatwave is most likely to have its biggest impact in the Sierra, accelerating snowmelt that has already been happening ahead of schedule.

Almost immediately on Friday, temperatures are expected to return closer to normal for early April.

"We’ll start to see the high-pressure system that’s causing this heat start to erode [on Friday] and move off to the east,” says National Weather Service meteorologist Sarah McCorkle, speaking to Bay Area News Group. “A trough is coming down from the north and we’ll see temperatures get back to normal.”

It still should be a pleasant weekend, but temps will be back in the 60s in SF. And then on Monday, expect gustier weather, possible rain, and much cooler temperatures.