A man walks through the rain in Sayville on Jan....

A man walks through the rain in Sayville on Jan. 17, 2010. Credit: Newsday File / Ed Betz

A massive storm system stretching from Florida to Canada is expected to drench Long Island with up to 2 inches of rain, prompting a flash flood watch and probably slowing commutes, according to the National Weather Service.

The cold front Sunday resulted in tornado watches across the South and dumped more than 2 inches of rain across Pennsylvania. Farther north in Maine, it's predicted to cause sleet and some snow.

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On Long Island, expect wind gusts Monday of up to 50 mph and possibly thunder and lightning, along with heavy rains throughout the day, said Matt Scalora, a National Weather Service meteorologist in Upton.

Tornado conditions are unlikely, he said.

"We're not expecting anything like that, but it's a pretty strong cold front," Scalora said.

The heaviest rains and wind gusts were likely to come in the middle of the day, but rain could fall during the morning commute and the beginning of the evening journey home, Scalora said.

A flash flood watch that began Sunday night remained in affect Monday morning and would last through the evening, according to the National Weather Service.

There is good news. Temperatures during the storm will be in the mid-50s, the warmest high recorded so far this January, Scalora said.

That means, he said, "It's all rain. No snow, no ice."

>> UPDATES: Click here to see traffic cameras and real-time congestion maps

>> TRACK YOUR FLIGHT: Get live updates on the status of flights out of MacArthur, and other area airports

Get the latest news and more great videos at NewsdayTV Credit: Newsday

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Get the latest news and more great videos at NewsdayTV Credit: Newsday

9 arraigned in missing girl case  ... Romantic spas in the winter ... What's up on Long Island ... Get the latest news and more great videos at NewsdayTV

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