Average Precipitation for Iowa (1981 – 2010)
Author: Bradley Miller
This map shows the average annual precipitation in Iowa over the 30-year period from 1981 to 2010. The data is displayed in inches and illustrates spatial patterns of rainfall across the state, highlighting regional climate variability. Precipitation tends to increase from northwest to southeast, with the driest regions in the far northwest and the wettest areas located in south-central and southeastern Iowa.
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Source:
Iowa Environmental Mesonet
Map generated on 17 Sep 2012 at 12:52 PM
Interpretation:
This map reflects Iowa’s gradient of annual rainfall, which is shaped by topography, storm track patterns, and atmospheric moisture flow. The data is important for understanding trends in crop water availability, drainage planning, hydrologic modeling, and drought risk.
Resolution:
County-level interpolation from long-term weather station data; displayed as a statewide static image
Suggested Use:
Useful for water resource planning, agricultural management, hydrological modeling, and climate research. Also valuable for contextualizing soil moisture variability, irrigation needs, and long-term landscape planning.
References:
Iowa Environmental Mesonet (IEM), Iowa State University
https://mesonet.agron.iastate.edu/