Iowa Environmental Mesonet

Iowa State University Department of Agronomy

The GIS page has everything GIS on the IEM

The National Weather Service [NWS] Cooperative Observer Program [COOP] is a nation-wide network of people making daily weather observations. These volunteers are invaluable in times of severe weather and heavy snowfall. Their observations also provide a 'ground truth' to compare against remote sensing techniques.

IEM News Items

Current Plots

Data + Summaries

Download Data:


COOP Data Applications:


High / Low Scatterplot
Scatterplot of high versus low temperatures for a given date and location.
Winter Min Low Temp Frequencies
Histogram showing the number of years that a certain low temperature threshold is exceeded.
Daily Temperature Spread
Histogram showing daily high/low temperatures.
Yearly Average Temperatures
For a date interval of your choice, get the yearly statewide average temperatures.
Observations by Month
View observations and estimates on a per station by per month basis.
Fall Freezing Dates
Statistics of dates for significant first fall freezes.
Snow Depth Duration
For a given date, how long will the snow stick around?
Daily Climate in Tables
Tables of daily temperature and precipitation climatology.
Daily Climate in Maps
Plots of daily extremes and averages with a GIS Ready! download of the data presented.
Daily Average Temperatures
Dynamically produced chart of average daily temperatures.
Yearly Average Temperatures
Plot average daily temperatures for a season or year of your choice.
Accumulated Precipitation Probabilities
Chart of precip probabilities for a time period of your choice.
Daily Temperatures Extremes
Plot average temperatures and extremes throughout a year.
Yearly Departures from Average
Plot average temperatures versus what actually occured during one year.
Accumulated Departures from Average
Plot an accumulated departure from average for rainfall and growing degree days for a time period of your choice!
Map Daily Observations
Generate maps of daily observations.