IEM Daily Bulletin for Apr 24 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 24 April 2026

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
Apr 23 9:08 AM	iem,main	✨ Add dew point depression plotting option https://mesonet.agron.iastate.edu/plotting/auto/?q=153 https://mesonet.agron.iastate.edu/plotting/auto/?q=159	Link
Apr 23 10:04 AM	iem,main	🐛 Address HML plotting quirks when flow is primary https://mesonet.agron.iastate.edu/plotting/auto/?q=160	Link
Apr 23 10:24 PM	iem,main	✨ Add RWIS download link to sites toolbar	Link
Apr 23 10:42 PM	iem,main	📝 Sundry updates per log review	Link
Apr 23 11:04 AM	pywwa,main	⬆️ Update EC MOS LDM feedtype to HDS	Link

Daily Feature

Early Spring Precipitation
Date: 23 Apr 05:30 AM
Votes: Good: 12   Bad: 0 Abstain: 0

While the recent rains have significantly helped Iowa's drought situation, portions of extreme northwestern Iowa have a bit to go yet before erasing analyzed drought over that portion of the state. The featured chart presents IEM estimated precipitation over the northwestern Iowa climate district during the months of February through April. Of course, the 2026 total still has eight more days to go, but the current total comes in about second driest over the past 25 some years. The 2026 total is above the top ten driest though as shown by the right hand side tables. A number of significant rainfall chances are in the forecast to close out April, but it remains to be seen if this driest area of the state will receive any of the largest forecast totals over Iowa.

The featured media can be generated on-demand here

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NWS Watch/Warning Summary for 12 AM 23 Apr 2026 - 12 AM 24 Apr 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	52	21	0	2	13	7	0	3
Svr Tstorm	187	64	4	6	25	37	5	4
Flash Flood	5	1	0	0	0	1	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: 226 Verified:  82 [36.3%]
Polygon Size Versus County Size            [32.6%]
Average Perimeter Ratio                    [30.3%]
Percentage of Warned Area Verified (15km)  [16.4%]
Average Storm Based Warning Size           [1678 sq km]
Probability of Detection(higher is better) [0.89]
False Alarm Ratio (lower is better)        [0.64]
Critical Success Index (higher is better)  [0.35]

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