IEM Daily Feature
Friday, 20 May 2022

Severe Warning Departures

Posted: 20 May 2022 05:30 AM

Severe weather mostly stayed outside of Iowa during the daylight hours on Thursday with southern Minnesota having another active day of severe weather this spring. One way to measure the amount of severe weather activity is to total up the number of Severe Thunderstorm Warnings issued by the NWS Weather Forecast Offices. The featured map presents a standardized departure which is the difference of this year's total versus a 21 year average and then divided by standard deviation over those same 21 years. The normalization allows for a bit more equal comparison and regional differences this year become more readily apparent. The NWS offices in Minneapolis and Aberdeen lead the way over the country.

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