Automated Data Plotter
This application dynamically generates many types of graphs. These graphs are derived from processing of various data sources done by the IEM. Please feel free to use these generated graphics in whatever way you wish. Reset App. The IEM Explorer application offers a simplified frontend to some of these autoplots.
Second, select specific chart options::
Plot Description:
Based on available hourly observation reports by METAR stations, this application presents the frequency of number of hours for a given month or season at a given threshold.If you pick a custom day of the year period that crosses 1 January, the year of the start date is used within the plot.
Updated 18 Sep 2018:Plotting tool was updated to consider dates prior to 1973 and to shade years that have more than 20% missing data. The hourly averages are based on years with sufficient data coverage.
Based on a sampling of recent timings for this application, plot generation time has averaged 6 seconds. Hold on for the plot is generating now!

IEM Daily Features using this plot
The IEM Daily Features found on this website often utilize plots found on this application. Here is a listing of features referencing this plot type.
- 02 May 2023: 30+ MPH Winds
- 03 Nov 2022: November Hours of 70+
- 26 Apr 2022: April Windy Hours
- 25 Jan 2022: January below Zero
- 24 Sep 2021: September 80+
- 06 Oct 2020: October 70+
- 17 Sep 2019: Steamy September
- 15 Feb 2019: Hours Below Zero
- 10 Sep 2018: 70+ Dew Points during September
- 23 Jul 2018: July Sub 60 Dew Points
- 20 Dec 2017: December Hours of 50+
- 29 Sep 2017: September 70+
- 21 Sep 2016: Muggy September