These atmospheric conditions produce frequently and rapidly changing weather conditions. The topography of the county also causes varying climatological conditions between the hilly uplands and valley lowlands. The growing season, from the date of the last frost in Spring to the date of the first frost in Autumn, lasts about 150-160 days. Broome County has an average annual precipitation of 37 inches based on 1958-1987 data. Most of this precipitation is derived from moisture-laden air masses originating in the Gulf of Mexico.
Monthly precipitation is distributed relatively evenly throughout the year.
The amount of snowfall varies sharply within Broome County, because of the sharp topographical differences between uplands and valleys. The City of Binghamton and the Towns, including Conklin, located in the river valleys receive about fifty inches annually, while the higher upland elevations commonly receive over ninety inches. Lower temperatures and humidity, combined with the rolling typography mean that tornadoes are a rate occurrence, and that the velocity of tornadoes is relatively low. From 1953-1991, the whole of New York State only had 189 reported tornadoes. Due to the distance from the coast and the intervening hilly typography, hurricanes, also, are almost unheard of.