Fog Thursday morning should burn off by 9 a.m. or so as the sun takes over, but it should return before dawn on Friday, when clouds are expected to roll in at night ahead of a possibly rainy Saturday afternoon, the National Weather Service said.
Sunday should be bright and clear — and so should the Monday to Wednesday period.
Temperatures, at least into Saturday, will keep evoking late summer instead of autumn, running from five to 15 degrees higher than usual, the weather service said.
Look for highs in the mid-70s during the day and in the low 60s at night, until clashing weather patterns over the weekend push temperatures down into the mid- to upper 60s during the day and the 50s at night, the weather service said.
Saturday might set a new high record high temperature, though that will depend on how quickly a possible storm arrives.
For Islip, the current record of 80 degrees was set in 1963, the first year the weather service’s records begin for that site.
The record that day at LaGuardia Airport, 82 degrees, was set in 1958. Kennedy Airport's record of 79 degrees dates back to 2008, New York City’s record of 87 was set in 1897, and Newark Liberty International Airport’s record of 84 was hit in 1958.
Stormy Saturday possible
The tri-state's weather over the next week or so will be driven by the weakening of what has been a lingering upper level high pressure system as a strong storm system quits the Rockies and northern Plains and heads north to Canada, according to the weather service’s Weather Prediction Center.
"This intense storm plays a key initial role in eroding the persistent warm ridge that has been anchoring in the eastern U.S.," it said.
At the same time, a low pressure system is "brewing over the southern Plains ahead of an upper trough sliding across the western U.S.," a combination that could help make for a stormy Saturday in the New York metropolitan area.
Before that, the upper level high pressure system, with its falling, drying air, should remain over this area, so both Thursday and Friday will be "mainly dry and unseasonably warm," the weather service said.
A modest cold front will sweep through the metropolitan area Thursday morning.
"Winds become north/northwesterly with the previous frontal passage today, helping to scour out any remaining stratus," the weather service said, referring to the kind of low, grey clouds that tend to appear in patches.
Friday should be mostly sunny, and then the clouds arrive that night.
By Saturday, there is a marginal risk of "isolated severe thunderstorms," according to the weather service’s Storm Prediction Center.
The "main threat at this time would be damaging winds," the weather service said. It predicted half an inch or so of rain as the storm is expected to move fairly quickly, with wind gusts blowing from the south and southwest hitting 30 mph during the afternoon and evening.
The odds of nightime showers, mainly from around 8 p.m. Saturday to 2 a.m. Sunday, are 50%, the weather service said.
"A return to more seasonable weather, if not a few degrees below normal, is forecast Sunday through Tuesday," it said. Then, "Milder temperatures return by mid-week."