Historical weather data, all-time temperature records, and monthly climate averages for Syosset, NY. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5 in Syosset sits right in the thick of spring's arrival, with average highs of 55° and lows of 40° across 77 years of data. The date has seen some wild swings, though — a balmy 73° back in 1988 and a bitter 24° low in 1995. Snow is nearly off the table at just a 1% chance, but there's still a roughly 1-in-3 shot at rain.
Syosset's weather has real teeth at its extremes — the mercury has soared to 104° (July 3, 1966) and crashed to -2° (January 21, 1985), a 106-degree range that speaks to the full brutality of the Northeast's seasons. The wettest single day on record dumped a remarkable 8.05 inches on September 29, 2023, while the snowiest dropped 30.3 inches in the historic January 2016 blizzard.
Summer is comfortably warm, peaking in the week of July 16–22 with average highs of 85°, while the coldest stretch — mid-January — averages just 38°. The wettest period falls in late July, averaging nearly an inch of rain per week, so pack accordingly for summer travel. Spring and fall offer mild shoulder seasons, with April highs around 59° and October around 65°.