Fresno may have seen its last triple-digit high temperature of the year with Monday’s high of 104.
Fresno recorded a 100-degree reading on Oct. 14, 1978 – the latest date for that kind of heat ever recorded in the city, said National Weather Service meteorologist Kevin Durfee.
Chance are slim that will happen again, though, he said. The reason is the calendar. With each passing day, the sun is getting lower in the sky and daylight is growing shorter. Thursday marks the first day of autumn, the equinox when daylight and night are in equal measure. After Thursday, the nights will grow longer until the winter solstice at Christmastime.
“To say whether it gets to 100 degrees or not again – it can still happen, but we are not expecting it,” said Durfee.
When falls arrives, it will feel more like late October. A cold front blowing in Wednesday will bring chilled air that will cool Thursday to a high in the 70s. Based on historical data, Fresno’s projected high of 73 degrees is average for Oct. 29, Dufree said.
“When autumn arrives Thursday morning, it will be blustery, cool, beautiful and refreshing,” Durfee said.
But conditions will warm up again as the highs head back into the 90s by the weekend, he said.
Monday’s air quality was unhealthy for all groups, and Fresno had the worst air quality in the nation, with Visalia a close second. Winds that begin blowing Wednesday night and continue Thursday will help scour the air of pollutants. Gusts Wednesday night could blow to 25 mph in the Valley.