Summer’s official start on Saturday and Father’s Day on Sunday will be accompanied by a heatwave.

The National Weather Service in Hanford is predicting temperatures as high as 10 to 15 degrees above normal for summer’s start in Fresno and other San Joaquin Valley locations.

While Thursday’s afternoon high for Fresno is forecast at 96 degrees, Friday is expected to hit 100, and Saturday 101 degrees.

Father’s Day — traditionally a day for barbecues and swimming — is forecast to top out at 103 degrees, followed by 104 on Monday.

High-Pressure System Will Persist Into Next Week

“High pressure will build over the region over the next few days bringing a warming trend with a return to triple-digit heat in the lower elevations. The pattern will persist well into next week,” says NWS Hanford in its forecast discussion.

Look for warming temperatures through the end of the week and into the start of next week. Sunday and Monday will be the hottest days, with highs as much as 10 to 15 degrees above normal for the beginning of summer. #CAwx pic.twitter.com/fLT3eU0znh

— NWS Hanford (@NWSHanford) June 18, 2020