Update 7:08 p.m.:
The National Weather Service has issued a "Severe Thunderstorm Watch" through 10 p.m. for Fairfield and New Haven counties.
The weather service's specific forecast for Darien was updated at 6:12 p.m. The forecast for tonight states:
"Showers and thunderstorms before 3am, then showers likely and possibly a thunderstorm between 3am and 5am, then a chance of showers and thunderstorms after 5am. Some storms could be severe, with hail, damaging winds, gusty winds, heavy rain, and frequent lightning. Low around 66. West wind between 6 and 11 mph. Chance of precipitation is 80 percent. New rainfall amounts between a quarter and half of an inch possible."
The forecast for tomorrow:
"A chance of showers and thunderstorms before noon, then a slight chance of showers and thunderstorms after 3 p.m. Mostly cloudy, with a high near 71. Northeast wind around 5 mph becoming south. Chance of precipitation is 40 percent."
Original article, 2:19 p.m.:
Damaging winds, large hail, frequent lightning and heavy rain could all be part of some severe thunderstorms that may hit Darien and the New York metropolitan region tonight, the National Weather Service warns.
At higher elevations in southwest Connecticut, thunderstorms could come this afternoon, according to the weather service's meteorologists.
The actual chance of a severe thunderstorm may not be so great, however. According to a "Hazardous Weather Outlook" issued by the National Weather Service at 10:15 a.m., the chance for severe thunderstorms is only "slight":
"The Storm Prediction Center has placed the entire [New York Metropolitan] area under a slight risk for severe weather today into this evening. The most probable impacts with thunderstorms during this period will be heavy downpours, but there is also a chance of strong, damaging winds and hail."
Could be bad
In a "Special Weather Statement" issued at 1:32 p.m., forecasters at the service announced:
"Severe thunderstorms are possible this afternoon and tonight. An approaching cold front will help trigger showers and thunderstorms in the very warm, humid and unstable air mass in place. Some thunderstorms could be severe, with damaging winds and large hail. Heavy rain and frequent cloud-to-ground lighting are also likely.
"The best chance for severe thunderstorms this afternoon will be across the lower Hudson Valley and the higher elevations of interior northeast New Jersey and southwest Connecticut, as scattered thunderstorms develop well in advance of the approaching front. Tonight this threat should then expand eastward to include all of northeast New Jersey, the New York City Metropolitan Area, western Long Island and southwest Connecticut as the front draws closer.
"Keep an eye to the sky for threatening weather this afternoon and evening, and keep informed [...]"
According to the National Weather Service's specific forecast for Darien, issued at 1:26 p.m., there is "a chance of showers and thunderstorms, mainly after 5 p.m. Mostly sunny, with a high near 80. South wind around 10 mph. Chance of precipitation is 30 percent."
For tonight, the weather service predicts "Showers and thunderstorms likely before 2 a.m., then showers likely and possibly a thunderstorm between 2 a.m. and 5 a.m., then a chance of showers and thunderstorms after 5 a.m.
"Some of the storms could produce small hail, gusty winds, and heavy rain. Mostly cloudy, with a low around 68. West wind between 5 and 9 mph. Chance of precipitation is 60 percent. New rainfall amounts between a quarter and half of an inch possible."