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::

Aggregate Statistics:
Start Date / Time (UTC, inclusive):
(YYYY/mm/dd HH24MI)
End Date / Time (UTC):
(YYYY/mm/dd HH24MI)
Which metric to plot:
Option to plot all or form set VTEC Events:
VTEC Phenomena and Significance 1
VTEC Phenomena and Significance 2
VTEC Phenomena and Significance 3
VTEC Phenomena and Significance 4
Only plot Emergencies / PDS ?
Color Ramp:
  Reverse Colormap?
Image Pixel Size @100 DPI
Image Resolution (DPI) (50 to 500)
Select Output Format:

Plot Description:

This application generates per WFO or state maps of VTEC event counts. The current three available metrics are:
  • Event Count: The number of distinct VTEC events. A distinct event is simply the usage of one VTEC event identifier.
  • Days with 1+ Events: This is the number of days within the period of interest that had at least one VTEC event. A day is defined within the US Central Time Zone. If one event crosses midnight, this would count as two days.
  • Percent of Time: This is the temporal coverage percentage within the period of interest. Rewording, what percentage of the time was at least one event active.
  • Rank of Event Count: The ranking from least to greatest of the given period's event count vs period of record climatology.
  • Departure from Average of Event Count: The number of events that the given period differs from the period of record climatology.
  • Standardized Departure from Average of Event Count: The departure expressed in sigma units of this periods event total vs the period of record climatology.

PLEASE USE CAUTION with the departure from average plots as they are not exactly straight forward to compute. If you are plotting small periods of time, individual events will heavily skew the averages. The exact start date of each event type is not an exact science due to the implementation of some products and other complexities. For Severe Thunderstorm, Tornado, Flash Flood, and Marine Warnings, the IEM has a special accounting of these back to 2002. For other event types, the archive starts with the VTEC implementation, which varies by product.

Note that various VTEC events have differenting start periods of record. Most products go back to October 2005.

Based on a sampling of recent timings for this application, plot generation time has averaged 7 seconds. Hold on for the plot is generating now!


View Data (as csv)   Download as Excel  
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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.