A heat record that had stood since 1896 was broken on Tuesday when the thermometer at Napa State Hospital reached 99 degrees.
This was one degree hotter than the record for May 26 that had stood for well over a century, said Roger Gass, a meteorologist with the National Weather Service.
While the heat in south Napa was less than 100 degrees on Tuesday, it reached over 100 degrees at many locations farther inland.
The heat moderated a bit on Wednesday, then drop some more on Thursday, before plunging into the 70s and low 80s on Friday, with the possibility of showers Friday night, Gass said.
Wednesday's Napa high was expected to be 95, with 91 forecast for Thursday. The mid- and upper-valley will be hotter, he said.
The record for Wednesday, May 27, is 102 degrees at Napa State set in 1984.
You can reach City Editor Kevin Courtney at email@example.com or at 707-256-2217.
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