Historical weather data, all-time temperature records, and monthly climate averages for Mount Sinai, NY. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 5th in Mount Sinai runs cool but not cold, with an average high of 54° and a low of 36° across 32 years of records. The date has seen a surprising 51-degree swing in extremes — from a 76° scorcher in 2010 to a bitter 25° low in 2016. There's roughly a 4-in-10 chance of rain today, though snow is essentially off the table.
Mount Sinai has seen weather go to genuine extremes — from a sweltering 101° in July 1999 to a brutal -7° in February 2015, a 108-degree range that captures just how wide Long Island's seasonal personality can stretch. The wettest single day on record dumped 6.87 inches on October 15, 2005, while a February 2013 nor'easter buried the area under 30.3 inches of snow.
Summer is the clear sweet spot, with average highs peaking around 84° during the third week of July and staying in the low 80s through August. Winter bottoms out in late January, when highs average just 37° — cold but manageable for the North Shore. If you're rain-averse, avoid mid-December, which is statistically the wettest stretch of the year.