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.


First, select a chart type::


Second, select specific chart options::

Select CONUS-Only State:
Start Timestamp (UTC):
(YYYY/mm/dd HH24MI)
End Timestamp (UTC):
(YYYY/mm/dd HH24MI)
Color Ramp:
  Reverse Colormap?
Image Pixel Size @100 DPI
Image Resolution (DPI) (50 to 500)
Select Output Format:

Plot Description:

This data is courtesy of Vaisala NLDN. The IEM processes a data stream by NLDN to construct this heatmap. The stroke density is computed over a two by two kilometer grid constructed using a US National Atlas Albers (EPSG:9311) projection. You are limited to plot less than 32 days worth of data at a time.

Note: Due to some lame reasons, it is difficult to document what data gaps exist within this dataset. In general, the coverage should be good outside of the major gap on 10 August 2020 due to the derecho power outage.


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!


If you notice plotting issues with the image above, please do let us know by providing the URL address currently shown by your web browser.

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.