Questions
Short answers about the figures and the site.
First published · revised
What is a climate normal?
The average of thirty years of observations at a weather station, computed by NOAA every ten years. The current set covers 1991-2020.
Why does my city show an airport?
Most large cities keep their official climate record at the main airport, where the National Weather Service observes around the clock. The page names the station and its distance from the center.
My town has no page. Why?
A place page shows one NOAA station's record, so it needs a station in the place. A place of 50,000 or more without a station has a page with NOAA's gridded normals for it beside its nearest records; a smaller town is listed, with its population and distance, on the page of the nearest station with a full record, and the search finds it there. The ZIP frost lookup gives the nearest stations too.
Are these forecasts?
No. Normals describe a typical year. Each place page links the National Weather Service forecast.
How current are the records and recent years?
They come from NOAA station data served by the Regional Climate Centers, read again each time the database is rebuilt (the methodology page gives the current edition); recent years count only when all twelve months are complete.
Can I reuse the data?
Yes. Each place page with its own NOAA station offers CSV and JSON downloads, and every ranking and the full tables are on the data page; the NOAA, NASA and Census source data are U.S. government works, and PlainClimate's tables are public domain (CC0 1.0). Credit the original source. The USDA 2023 hardiness zone listings belong to Oregon State University and are not in the downloads.