'Rare Summer Rainstorm' To Drench Long Island

Rain is expected to fall on Long Island for a solid 12-hour stretch Friday afternoon into Saturday morning, according to the National Weather Service.

It will be a "rare summer rainstorm," AccuWeather says, noting that most summer rainfall is limited to a few hours.

The storm will roll eastward along a zone of temperature contrast with unusually cool air to the north and warm, sticky air to the south, according to AccuWeather.

"This type of setup has the potential to deliver very heavy rainfall and raise the risk of flooding," AccuWeather Chief Meteorologist Elliot Abrams says.

Winds on Friday night and Saturday could be in the 30-mph range and the NWS says it can't "rule out a few gusts to 40 mph."

"If this were winter time, the winter storm watches would be going up!" says Joe Cioffi, a meteorologist for WPIX-TV and FiOS1 News.

The rain is expected to end Saturday morning as high pressure builds in from the north.

The full forecast:

Thursday- Mostly cloudy, with a high near 77. Southwest wind 6 to 11 mph.

Thursday Night- A 50 percent chance of showers and thunderstorms. Mostly cloudy, with a low around 72. Southwest wind 6 to 11 mph.

Friday- A chance of showers and thunderstorms, then showers likely and possibly a thunderstorm after 2pm. Cloudy, with a high near 81. Southwest wind 5 to 9 mph becoming southeast in the afternoon. Chance of precipitation is 60%. New rainfall amounts between a quarter and half of an inch possible.

Friday Night- Rain likely and possibly a thunderstorm. Cloudy, with a low around 67. Northeast wind 8 to 14 mph. Chance of precipitation is 70%. New rainfall amounts between three quarters and one inch possible.

Saturday- A 40 percent chance of rain before 9am. Mostly cloudy, with a high near 78. Breezy.

Saturday Night- Partly cloudy, with a low around 64.

Sunday- Sunny, with a high near 79.

Photo: Flickr/CreativeCommons/CGP Grey