Few things in life are certain but Saturday's sunshine will be followed by rain, mainly after 8 p.m., the Islip-based National Weather Service said, assessing the odds of downpours at 100%.
The rest of the Monday-to-Friday stretch — including Thanksgiving — will be at least partly sunny, though Wednesday also might see some showers, forecasters said.
Bundle up on Saturday morning — the wind chill will feel like 25 to 35 — about 20 degrees below the high for the day.
On Sunday, the odds of showers are 90%, though mostly before midday, and the high should hit 49, the weather service said.
Predicting as much as one inch, the weather service issued a three-hour coastal flood advisory, starting at 8 a.m. on Sunday, for northern Nassau and northwestern Suffolk.
"Shallow flooding is expected in the most vulnerable locations near the waterfront and shoreline," the weather service said, estimating floods as high as two feet.
The odds of rain, it said, dwindle to 20% before midnight on Sunday; the nightime low is 35.
Both Monday and Tuesday should be sunny, with highs in the upper 40s to low 50s, the weather service said.
Wednesday might see rain: the odds are 30%, forecasters said.
Paradegoers or anyone wishing to work off a Thanksgiving feast can look forward to sunshine on Thursday. The holiday and Friday should be clear, with temperatures once again rising to the mid 40s.