Hot start to weekend, isolated storm before cooldown

Today will be the warmest day of the year so far, with readings touching 90 degrees under bright sunshine.

An air quality alert has been issued by the Mid-Ohio Regional Planning Commission for levels of ozone considered unhealthy for sensitive groups ("children, elderly, people with asthma or COPD"), who are advised to "limit prolonged or strenuous outdoor activity."

Today will be the warmest day of the year so far, with readings touching 90 degrees under bright sunshine. The summer heat will continue beneath a sprawling upper-level ridge of high pressure over the central and eastern portions of the country.

Near the surface, high pressure over the Northeast will maintain a dry northeasterly flow of unseasonably warm air and low humidity. A backdoor cold front will slip south through the region Saturday, possibly sparking an isolated storm over the eastern part of the state. Readings will reach the upper 80, before slightly cooler air arrives, under mostly sunny skies.

Noticeably cooler air will filter into the Ohio Valley early next week, with seasonable temperatures in the 70s and mainly sunny skies.

Forecast

• Friday: Sunny, hot. High 92
• Tonight: Moonlit sky, mild. Low 65
• Saturday: Mostly sunny., isolated storms. High 88
• Sunday: Partly sunny. High 85 (63)
• Monday: Mostly sunny. High: 82 (58)
• Tuesday: Mostly sunny, cooler, cooler. High 76 (57)
• Wednesday: Mostly sunny. High 74 (52)
• Thursday: Seasonable sunshine. High 77 (54)