Yorktown Weather Station History
by Dr. Jerome S. Thaler
The climate record of Yorktown is based on weather records dating back to 1940. At three different sites in the town since that year, daily temperatures, precipitation and snowfall, as well as other weather events, have been faithfully monitored.
Each weather station was equipped by the National Weather Service and the daily record is sent once a month to the National Weather Records Center in Asheville, North Carolina where it is included in a monthly summary published for all New York State reporting stations. The data supplied is used for climatological purposes but not for forecasting.
The present Yorktown Weather Station is the only official station in northern Westchester and as such represents the climate of that part of the county. In the past, from 1888 to 1980, a station was maintained in Carmel, Putnam County, about 12 miles from the present Yorktown Station.
In 1940, George Hancock of the Yorktown Water Department, in conjunction with his duties, set up the first station near the present Yorktown Town Hall, which is at an elevation of 450 feet above sea level. After ten years of daily weather observations, the station was relocated to Shrub Oak, five miles to the north, near the Water Department building off Sunnyside Street at an elevation of 420 feet. After his retirement in 1967, daily readings were continued by Water Department employees to April 1970, when the station was moved to a home site one mile to the west, off Strawberry Road. Daily readings were taken there till November, 1971.
In June, 1964, Jerome S. Thaler established a weather station behind his home on the northwest slope of French Hill, elevation 670 feet, about one mile west of the Yorktown Heights Post Office. Daily readings have been taken since then to the present time at the location.
A temperature comparison can be made between the Shrub Oak and French Hill sites for the seven years of concurrent daily readings. This shows that daily low temperatures, particularly in winter are often between five and ten degrees colder in Shrub Oak, while daily high temperatures can be one to five degrees colder at the French Hill site. The January averages show Shrub Oak to be only 0.2 degrees colder than French Hill. July averages show French Hill to be 1.3 degrees warmer. Annually for the common period, Shrub Oak had an average temperature of 49.1 degrees Fahrenheit and French Hill was 0.3 degrees Fahrenheit warmer.
In 1985, the weather station of Yorktown Heights 1W, one of three official U.S. Weather Service cooperative stations in Westchester, became part of the National Historical Climate Network of 1200 active weather stations that have monitored temperature, rain and snowfall for at least 80 years. This resulted when the long-term station at Carmel managed by the New York City Water Department ceased to take daily temperature readings in 1981. The Carmel station located 11 miles to the northeast had monitored such readings since 1888 and was considered to be a benchmark climate station highly useful in the determination of long-term climate trends. Employing the 16 years of concurrent records of both stations, the Carmel daily weather observation record was adjusted to that of Yorktown Heights thus maintaining the continuity of an unbroken 111 year record through 1998.
In addition to the present Yorktown Heights station on French Hill, the New York City Water Department monitors precipitation with a rain gauge located just east of the northbound Taconic Parkway on the south side of the Croton Reservoir. This gauge had registered continuous readings since 1860 and is the oldest of the New York City watershed systems of rain gauges.
From long term weather stations, climatic norms are obtained, and climate trends determined. First and last frost of the season can be obtained, as well as all kinds of snowfall data. Weather stations provide information for those who would be weatherwise.