IEM Daily Bulletin for May 28 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 28 May 2026

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
May 27 1:56 PM	iem,main	✨ Allow time period to cross 1 Jan https://mesonet.agron.iastate.edu/plotting/auto/?q=73	Link

Daily Feature

2026 Corn Planting Progress
Date: 27 May 05:30 AM
Votes: Good: 13   Bad: 0 Abstain: 0

USDA NASS published their weekly crop progress update yesterday and estimated 94% of Iowa's corn crop now planted. The featured map presents the statewide estimates with a departures against a simple and linear interpolated ten year average valid 24 May. All of the major corn producing states are shown in good shape. The mostly dry weather this week will likely push Iowa's value to near 100% by next week as the spring planting season draws to a close.

The featured media can be generated on-demand here

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NWS Watch/Warning Summary for 12 AM 27 May 2026 - 12 AM 28 May 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	3	0	0	0	0	0	0	0
Svr Tstorm	105	0	3	0	0	0	0	1
Flash Flood	26	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: 108 Verified:  52 [48.1%]
Polygon Size Versus County Size            [23.9%]
Average Perimeter Ratio                    [22.3%]
Percentage of Warned Area Verified (15km)  [17.4%]
Average Storm Based Warning Size           [1909 sq km]
Probability of Detection(higher is better) [0.84]
False Alarm Ratio (lower is better)        [0.52]
Critical Success Index (higher is better)  [0.44]

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