The heat is on — but not for long!

The Big Apple shattered an 85-year-old heat record Wednesday with sunny, summer-like temperatures that soared to 90 degrees, fit for a day at the beach, meteorologists said.

The mercury in Central Park hit a high of 90 degrees at around 2:15 p.m. — making it the hottest April 15 on record in the city since 1941, when it reached 87 degrees.

“It would be a nice day to go to the beach — but not to jump into the water because it’s still very cold,” AccuWeather Senior Meteorologist Matt Benz said Wednesday morning.

Thursday is also expected to be blissfully warm with a high of 89 degrees — and the steamy spring heat will stick around until Friday, which will reach a high of 80, according to forecasters.

But the dreamy dose of summer is will likely plunge back into the 50s and 60s over the weekend and into Monday, Benz said.

“This weekend, it’s back to a more April-like reality,” he said.“It will feel much cooler.”

New Yorkers flocked outside Wednesday to bask in the warm rays after shivering through a historically brutal winter and a recent cold snap.

The unseasonably high temps are fueled by stormy weather across the western US, which has caused pressure to keep cold air from cooling parts of eastern US.

“There’s a large ridge of high pressure,” Benz said. “That’s favorable for us in terms of warmth.”

Areas just north of New York City, such as Westchester County,  may also be struck by stormy weather on Wednesday evening with strong winds and downpours, Benz said. 

Monday and Tuesday are forecast to fall into the 50s and the rest of the month will largely be back to “average” April temperatures in the 60s, Benz said.

“We do have a cold shot on Monday and Tuesday,” he said.  “That will be a shock to the system after the heat.”