Prepare to swoon. Temperatures are expected to reach record-breaking highs today as a warm southwesterly wind swoops through the Northeast.

At New York City, meteorologists predict the thermometer will reach 86 degrees today, more than 20 degrees higher than the mid-April average high.

The Central Park record for April 20 is the 90 degrees recorded on this date in 1927. Temperatures at La Guardia Airport and at Long Island’s Islip Airport – where weather records don’t date back as far – are expected to break the records for the date.

Temperatures at John F. Kennedy International Airport were forecast to hover in the high-70s, and ocean breezes were expected to keep the South Shore of Long Island cool.

“From time to time, we get these spurs of warm air,” a meteorologist at the National Weather Service at Upton on Long Island, Michael Silva, told The New York Sun. “It is not common, but it does occasionally happen.”

Nor does Mr. Silva regard the mid-April heat wave as an indication of the summer to come.

“It is hard to use one specific instance to determine what is going to happen in the course of three or four months,” he said.

But for sun-soakers, the day promised clear skies and cool breezes, with humidity of only 30% but a slight chance of thundershowers in late afternoon. Even if it proves to be a perfect time to venture outdoors or perhaps catch some rays in the park, it may still be too soon to skip off to the beach, as ocean water temperatures promised to remain in the 40s.

Still, Mr. Silva advised taking care to drink plenty of fluids and wear sunscreen.

“Any time the temperatures come close to the 90s, it is better to just be safe,” he said.

Also remaining on the safe side was the National Weather Service, which issued a fire weather watch for today for the tri-state area. The low humidity, coupled with gusty winds, often creates prime conditions for brush fires, Mr. Silva said.

Temperatures are not expected to soar high enough to trigger an emergency response from the city’s Department of Emergency Management. Typically, the decision to use the city’s emergency cooling centers is based on multiple days of 90-degree-and-above weather.

“That threshold is usually determined by ongoing conditions, and 86 is still too cold a day to be taking those precautions,” a spokesman for the city agency, Jarrod Bernstein, said.

The southwesterly wind may instead wage an assault on allergy-sufferers, as pollen counts are expected to rise throughout the region.

Still, allergies or no allergies, Mr. Silva recommends that people get outside. This gust of fortune is not expected to last beyond tomorrow, when temperatures will return to the 60s, he said.