Historical weather data, all-time temperature records, and monthly climate averages for Rotterdam, NY. Explore typical weather conditions by week for trip planning, and see how today compares to the historical record.
April 4th in Rotterdam sits at that classic in-between moment: an average high of 51° and low of 33°, with winter not quite done fighting. The date has seen a 65-degree swing across the record books — from a bitter 14° in 1954 to a remarkable 79° in 1950 — and there's still a 1-in-8 chance of snow today.
Rotterdam's weather has real range. The thermometer has hit 100° in July and plunged to -28° in January, a 128-degree spread that speaks to the full force of a continental upstate New York climate. The single wildest day on record was September 16, 1999, when 5.6 inches of rain fell, and the Blizzard of '93 dropped 22 inches of snow in a single day.
Summer is the sweet spot here: highs average 84° in late July, and the wettest stretch of the year arrives right on its heels in late July as well, averaging nearly an inch of rain per week. If you're avoiding the cold, steer clear of mid-January, when average highs barely crack 30°. Spring and fall offer mild relief, with April averaging 58° and October 61°.