Updated 3:24 p.m.
FAIRFIELD COUNTY, Conn. Fairfield County is set to be hit by heavy showers, thunderstorms and damaging winds this evening, the National Weather Service said Thursday.
An isolated tornado is possible, the weather service said.
"At this time this appears to be a significant impact event with the potential for widespread tree damage in some areas and a significant number of power outages," says a statement on the state Department of Emergency Management and Homeland Security's website.
The severity of the storms depends on how warm it gets Thursday afternoon, the statement says.
"Towns can expect that any severe storms may contain strong winds, large hail and dangerous lightning," the statement says. "Torrential rainfall in these storms has the potential to result in a quick 2 to 4 inches of rain in a few towns that may result in urban and some small stream flooding."
Connecticut Light & Power says it is making preparations to respond to the storms. The utility already has requested assistance from crews in nearby states. Gov. Dannel Malloy has partially activated the state's Emergency Operations Center on Thursday afternoon to quicken the response to power outages and any damage.
The threat of severe weather would "slowly decrease" after 10 p.m. though storms may continue throughout the night, the Department of Emergency Management says.
Rain may return Friday afternoon, along with temperatures in the low 90s. There also is a chance of showers Saturday, and the weekend won't be as hot, with temperatures around 83, the National Weather Service says.