IEM Daily Bulletin for May 4 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 04 May 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 3 May 2026 - 12 AM 4 May 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	13	0	0	0	0	0	0	0
Flash Flood	0	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:  12 Verified:   2 [16.7%]
Polygon Size Versus County Size            [15.9%]
Average Perimeter Ratio                    [21.2%]
Percentage of Warned Area Verified (15km)  [7.7%]
Average Storm Based Warning Size           [1840 sq km]
Probability of Detection(higher is better) [0.48]
False Alarm Ratio (lower is better)        [0.83]
Critical Success Index (higher is better)  [0.14]

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): 1,453
• Mastodon / Fediverse: 13
• Slack: 31
• Twitter/X: 6,849
• HTTP Webhooks: 109
• Weather.IM Jabber Chatrooms: 7,983