Severe thunderstorm warnings have been issued for Tolland and Windham counties through 6:45 p.m.
The storms are bringing heavy rain, gusty winds, vivid lightning, and even some hail to several towns.
Flash flood warnings have been issued for the Hartford area until 8 p.m. and for southern Windham County until 8:15 p.m.
Severe thunderstorm warnings for Litchfield and Hartford counties have since expired.
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A severe thunderstorm watch has been issued for the entire state through 8 p.m. Friday.
Eversource was reporting more than 4,500 customers without power as of 5:15 p.m.
Friday marked the fifth day of a heat wave with high humidity pushing heat indices above 100 at times.
Scattered thunderstorms are likely this afternoon and heavy rain, lightning and gusty winds are all possible.
The threat of storms forced the PGA Tour to make some changes to Round 2 of the Travelers Championship in Cromwell.
The tour decided to move up tee times by one hour on Friday morning.
The weather will be pretty much the same all weekend and we will have afternoon storms.