Long Island is looking at a possible 21/2 to 31/2 inches of rain, most falling Wednesday into Thursday. But at the end of that cold, rainy tunnel is a forecast of 70 degrees or above for some noncoastal areas on the first day of May, forecasters say.

"Steadier, heavier rain" was expected to move into Nassau in time for Wednesday's early morning commute, spreading eastward, said Tim Morrin, National Weather Service meteorologist in Upton. The heaviest rainfall was expected roughly from 8 p.m. Wednesday to 3 to 4 a.m. Thursday, Morrin said, with Thursday morning's commute also possibly affected by lingering precipitation.

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A flood watch is in effect starting Wednesday afternoon and ending Thursday morning, with potential for flooding of low-lying and poor drainage areas, the weather service said.

Temperatures Wednesday were expected to be in the low 50s, about 10 degrees below normal, said Lauren Nash, also a meteorologist in Upton. As for Thursday? A high of 72 was forecast for Long Island MacArthur Airport, which hasn't seen 70 since Oct. 17, 2013.

Based on data since 1984, April 9 is the average date for temperatures there to crack 70, said Joe Pollina, also a meteorologist in Upton. This year would be the third time that was delayed until May, the first being 1984, when the area had to wait until May 20 for 70 degrees to arrive.