IEM Daily Bulletin for Apr 15 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 15 April 2026

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
Apr 14 9:59 AM	iem,main	📝 Sundry updates per review	Link
Apr 14 10:24 PM	pyiem,main	✨ Bundle NWS Counties/Zones circa 16 Apr 2026 closes #1144	Link
Apr 14 10:30 PM	pyiem,main	📝 Denote 1.27.0 Release	Link
Apr 14 7:01 PM	iem-web-services,main	🚧 Add debug for issue in the wild	Link
Apr 14 10:46 PM	iem-web-services,main	🐛 Fix transient meteobridge bug with pyiem bump	Link

Daily Feature

Max April Dew Points
Date: 14 Apr 05:30 AM
Votes: Good: 10   Bad: 0 Abstain: 1

It certainly felt a bit like summer on Monday with temperatures in the upper 70s and low 80s along with very muggy for April humidity levels. The featured chart presents the hourly maximum reported dew point temperatures for Ames during April. Observations on Monday were not too far from these maximums shown and even tied a maximum of 64°F at 10 PM. The heat and humidity helped to fire late afternoon thunderstorms over northern Iowa. We'll have more of the same through out this week before cooler and less humid weather arrives for the upcoming weekend.

The featured media can be generated on-demand here

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NWS Watch/Warning Summary for 12 AM 14 Apr 2026 - 12 AM 15 Apr 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	60	11	3	11	1	0	0	3
Svr Tstorm	245	43	18	20	12	5	0	7
Flash Flood	24	3	0	3	0	2	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: 286 Verified: 127 [44.4%]
Polygon Size Versus County Size            [32.6%]
Average Perimeter Ratio                    [38.2%]
Percentage of Warned Area Verified (15km)  [22.5%]
Average Storm Based Warning Size           [1411 sq km]
Probability of Detection(higher is better) [0.89]
False Alarm Ratio (lower is better)        [0.56]
Critical Success Index (higher is better)  [0.42]

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