Cooperative Observer Program

Programs and Information

National Co-op Program & National Co-Op Quarterly Newsletter
WxCoder Program
WxCoder Users Manual (4MB pdf file)
CoCoRahs and State Newsletters

Daily Cooperative Precipitation/Snowfall Messages

NOWData - 2 years of online data including Daily/Monthly/Yearly Cooperative Observations
Daily Hydrometeorological Products
Local Cooperative Observation

Cooperative Observer Equipment

History of the Cooperative Observer Program

The history of taking weather observations dates all the way back to the colonial days. The earliest known records are those of John Campanius Holm who took weather observations in the mid-1600s. After him, weather records by famous people such as George Washington, Thomas Jefferson and Benjamin Franklin have also been found and archived. Thomas Jefferson recorded an unbroken weather record from 1776 until 1816, and George Washington took observations until just days before he died.

However, it was Thomas Jefferson who first envisioned a network of weather observers. He managed to recruit volunteer weather observers in six states including Virginia, Massachusetts, Pennsylvania, Connecticut, New York and North Carolina. In 1849, the Smithsonian Institute set up a system for receiving weather data from telegraph companies, via the telegraph, and used the data to produce weather charts. At the time, there were 150 volunteers sending in their weather observations.

The Weather Bureau (now the National Weather Service) was created under the Organic Act in 1890 and the COOP program was soon transferred into their responsibility. By then, the number of weather observers had grown to around 2,000 stations. However, it wasn't until 1953 that the push was made to expand the network across the country. Dr. Helmut Landsberg conducted a study with Iowa State University and came to the conclusion that an observation site was needed every 25 miles. This is the system that the National Weather Service uses today. By 1990, the number of observers had grown to 10,000 stations, and today there are over 12,000 COOP stations.