IEM Daily Bulletin for May 16 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 16 May 2026

News

No news is good news

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Daily Feature

Needed Drink
Date: 15 May 05:30 AM
Votes: Good: 11   Bad: 1 Abstain: 0

After a very wet April, May has been the exact opposite with very little rainfall to speak of. An unofficial IEM Iowa statewide estimate indicates the first 14 days of May being the driest on record since at least 1893. Thankfully, this situation is about to change and the subject of today's featured map. The map depicts Weather Prediction Center's seven day precipitation forecast along with the latest US Drought Monitor released on Thursday. The entire state is shown in the 1.5 to near three inch range.

The featured media can be generated on-demand here

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NWS Watch/Warning Summary for 12 AM 15 May 2026 - 12 AM 16 May 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	4	2	2	0	1	0	0	0
Svr Tstorm	106	53	8	2	26	11	11	4
Flash Flood	2	0	0	0	0	0	0	---

ARX = LaCrosse, WI DVN = Davenport, IA DMX = Des Moines, IA OAX = Omaha, NE FSD = Sioux Falls, SD

IEM Cow Report

SVR+TOR Warnings Issued: 107 Verified:  38 [35.5%]
Polygon Size Versus County Size            [31.7%]
Average Perimeter Ratio                    [30.1%]
Percentage of Warned Area Verified (15km)  [14.6%]
Average Storm Based Warning Size           [1749 sq km]
Probability of Detection(higher is better) [0.77]
False Alarm Ratio (lower is better)        [0.64]
Critical Success Index (higher is better)  [0.32]

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