'Severe Thunderstorm Watch' Through 10 P.M.

Update 1:58 p.m.:

United Way of Connecticut has advice for safely getting through a severe thunderstorm and the possible flooding and power outages that may come with it.

Update 1:47 p.m.:

In addition to the "Severe Thunderstorm Watch" issued by the National Weather Service, the organization also issued an "Urban and Small Stream Flood Advisory" at 1:02 p.m. for much of southern Connecticut, including Fairfield County.

The advisory is in effect until 2:30 p.m. The weather service says, "Small creeks and streams may flood quickly, possibly covering roads and flooding nearby low areas."

The weather service's "Doppler radar was tracking an area of thunderstorms with heavy rainfall moving northeast at 25 mph. Rainfall rates of around an inch [...] per hour will be possible."

Update 1:34 p.m.:

The National Weather Service at 1:05 p.m. issued a "Severe Thunderstorm Watch" statement covering all of Connecticut, taking effect immediately and lasting until 10 p.m.

Original article:

Flash Flooding Threat for Darien in P.M. & Friday A.M. Thunderstorms

Flash flooding is possible from Thursday afternoon through Friday morning around the New York metropolitan area, including southern Fairfield County, according to the National Weather Service.

Thunderstorms will likely bring rain overnight to Darien (there's an 80 percent chance, they say), and possibly as early as Thursday afternoon (only a 30 percent chance), the weather service predicts.

Some parts of Darien are prone to flooding in very heavy rain, including part of Heights Road in downtown Noroton Heights and under the railroad overpass on the Post Road in downtown Darien (see picture accompanying this article).

"A strong cold front will approach from the west today and move through the area this evening into early Friday morning," the weather service said in a "Hazardous Weather Outlook" statement issued at 5:51 a.m. for the New York metropolitan area and much of Connecticut, including Darien and southern Fairfield County.

"Showers and thunderstorms along and ahead of the cold front will develop late this afternoon to the north and west of New York City and then spread eastward through this evening," the statement continued.

"There is the potential for a few storms to become severe with damaging winds. The best chance for severe weather will be to the north and west of New York City. In addition, the air mass is very moist, increasing the threat of localized flash flooding."

Here's the Darien-specific forecast from the National Weather Service from this afternoon through the weekend:

• Thursday afternoon: A chance of showers and thunderstorms, mainly after 3 p.m. Some of the storms could produce heavy rain. Partly sunny, with a high near 84. Southwest wind around 10 mph. Chance of precipitation is 30 percent.
• Thursday night: Showers and thunderstorms, mainly before 4 a.m. Some of the storms could produce gusty winds and heavy rain. Low around 64. South wind 5 to 8 mph becoming northwest after midnight. Chance of precipitation is 80 percent. New rainfall amounts between a half and three quarters of an inch possible.
• Friday: Mostly sunny, with a high near 76. Northwest wind 10 to 15 mph.
• Friday night: Partly cloudy, with a low around 49. Northwest wind 10 to 13 mph.
• Saturday: Sunny, with a high near 69. Northwest wind around 9 mph.
• Saturday night: Mostly clear, with a low around 47.
• Sunday: Sunny, with a high near 70.
• Sunday night: Partly cloudy, with a low around 56.