IEM Daily Bulletin for Apr 3 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 03 April 2026

News

---

Title: 1 April IEM Outage [resolved]
Date: 02 Apr 10:55 AM
Author: Daryl Herzmann
link

Unfortunately no April's Fools joke here as the IEM website was very degraded between about 2 and 7 PM on 1 April 2026. A back-end file server bricked itself, the replacement hardware had two memory stick failures and then refused to properly boot, the third replacement hardware attempt wouldn't find its boot drives, then yours truly (daryl) lost his mind and messed all kinds of things up. Not a good day. There was no data loss from this adventure somehow, so will try to avoid such horrors in the future. Thanks for your patience.

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
Apr 2 2:48 PM	iem,main	✨ Add day-of-year option to SPC outlook heatmap https://mesonet.agron.iastate.edu/plotting/auto/?q=200	Link
Apr 2 2:50 PM	iem,main	📝 Sundry updates per log review	Link

Daily Feature

Needed Wet Start to April
Date: 02 Apr 05:30 AM
Votes: Good: 15   Bad: 1 Abstain: 0

The featured map combines Weather Prediction Center seven day precipitation forecast with last week's Drought Monitor. The prediction paints a much needed wet start to April over Iowa. It is getting down to crunch time for precipitation deficits to be made up prior to the start of the growing season. It is also a good time to make up such deficits as it is still too early for farmers to plant crops and soils are no longer frozen. The only downside to this forecast is far western Iowa with totals that are not much higher than climatology this time of year, but something is better than nothing!

The featured media can be generated on-demand here

.

NWS Watch/Warning Summary for 12 AM 2 Apr 2026 - 12 AM 3 Apr 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	24	7	0	6	2	0	0	2
Svr Tstorm	83	19	0	11	8	0	0	1
Flash Flood	3	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: 105 Verified:  38 [36.2%]
Polygon Size Versus County Size            [34.6%]
Average Perimeter Ratio                    [33.2%]
Percentage of Warned Area Verified (15km)  [19.2%]
Average Storm Based Warning Size           [1434 sq km]
Probability of Detection(higher is better) [0.75]
False Alarm Ratio (lower is better)        [0.64]
Critical Success Index (higher is better)  [0.32]

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): 1,899
• Mastodon / Fediverse: 48
• Slack: 175
• Twitter/X: 17,054
• HTTP Webhooks: 51
• Weather.IM Jabber Chatrooms: 15,460