IEM Daily Bulletin for Apr 19 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 19 April 2026

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
Apr 18 9:05 PM	iem,main	🩹 Stop the hammering	Link

Daily Feature

No feature posted

NWS Watch/Warning Summary for 12 AM 18 Apr 2026 - 12 AM 19 Apr 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	0	0	0	0	0	0	0	0
Svr Tstorm	25	0	0	0	0	0	0	0
Flash Flood	1	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:  25 Verified:   6 [24.0%]
Polygon Size Versus County Size            [30.9%]
Average Perimeter Ratio                    [27.7%]
Percentage of Warned Area Verified (15km)  [5.7%]
Average Storm Based Warning Size           [2481 sq km]
Probability of Detection(higher is better) [0.39]
False Alarm Ratio (lower is better)        [0.76]
Critical Success Index (higher is better)  [0.17]

IEMBot Social Media Posts

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