IEM Daily Bulletin for Apr 27 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 27 April 2026

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
No code commits found in previous 24 Hours

Daily Feature

No feature posted

NWS Watch/Warning Summary for 12 AM 26 Apr 2026 - 12 AM 27 Apr 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	35	0	0	0	0	0	0	5
Svr Tstorm	153	0	0	0	0	0	0	2
Flash Flood	9	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: 178 Verified:  78 [43.8%]
Polygon Size Versus County Size            [32.0%]
Average Perimeter Ratio                    [33.0%]
Percentage of Warned Area Verified (15km)  [22.6%]
Average Storm Based Warning Size           [1477 sq km]
Probability of Detection(higher is better) [0.85]
False Alarm Ratio (lower is better)        [0.56]
Critical Success Index (higher is better)  [0.41]

IEMBot Social Media Posts

IEMBot can be configured to post messages to a number of social media services. More details: IEMBot Homepage.

Posts yesterday per supported service:

• ATMosphere (bluesky only attm): 1,836
• Mastodon / Fediverse: 36
• Slack: 52
• Twitter/X: 15,936
• HTTP Webhooks: 307
• Weather.IM Jabber Chatrooms: 13,917