Divisional Annual and Monthly Modified Growing Degree Day Units

Modified growing degree days (MGDD) are a refined version of growing degree days (GDD), which are used to estimate the growth and development of plants and insects during the growing season. MGDDs take into account both lower and upper temperature thresholds to provide a more accurate measure of growth potential.

These charts show annual and monthly modified growing degree day units for Wisconsin’s nine climate divisions, using data from the Midwestern Regional Climate Center. They use 50 and 86 degrees Fahrenheit for the base and cutoff temperatures, respectively, which are commonly used to monitor the development of corn.

Modified growing degree days also help in predicting the emergence and activity of pests, allowing for timely interventions. More broadly, they provide insights into the impact of climate variability on agricultural productivity.

Learn how to calculate growing degree days


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Expanded Tabular Data