The purpose of this page is to provide a one-stop view of summarized IEM Climodat data for a period of your choice. Once you have configured your favorite sites, please bookmark the page. There are options presented on this page on how to compute Growing Degree Days. Here is a description of the three options.
- base: This is the base temperature (F) to substract the daily average [(high + low) / 2] temperature from. The resulting value is always non-negative.
- floor: If the high or low temperature is below this value, the temperature is set to this value before the averaging is done. Delete the entry to remove this calculation.
- ceiling: If the high temperature is above this value, the high temperature is set to this value prior to averaging. Delete the entry to remove this calculation.
Updated 4 Oct 2018: Model based solar radiation values are now included. These values are based on the combination of NASA MERRA, NARR, and HRRR data. See IEM Autoplot 38 for a bias assessment of these values.
Available States with Data
Available Stations within Selected State
The following table is valid for a period from 01 May 2023 to 26 Sep 2023 (inclusive).
"Climo" is the climatology value, which is computed over the period of record since 1951.