IEM Daily Bulletin for Mar 12 2026

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 12 March 2026

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
Mar 11 1:53 PM	iem,main	🔨 Replace DWD usage with ECMWF IFS	Link
Mar 11 1:54 PM	iem,main	📝 Sundry updates per log review	Link

Daily Feature

Remarkable Warm Front
Date: 11 Mar 05:30 AM
Votes: Good: 17   Bad: 0 Abstain: 0

A significant severe weather event developed on Tuesday from northern Illinois/Indiana back southwest into Texas. The rough weather clipped southeastern Iowa as well with powerful storms developing during the late afternoon hours along and near a very strong surface warm front. The featured screenshot is from the ISU Soil Moisture Network homepage showing 3:30 PM air temperatures over southeastern Iowa on Tuesday. The 81.5°F plotted was near West Point and the 59.4°F was just over 30 miles away to the north near Crawfordsville. This temperature contrast made for a remarkable warm front due to the large temperature change over a very short distance. Strong warm fronts like these are typically trouble for severe weather as storms are focused along the boundary and the boundary helps to provide spin to the storms to produce large hail and even tornadoes.

The featured media can be generated on-demand here

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NWS Watch/Warning Summary for 12 AM 11 Mar 2026 - 12 AM 12 Mar 2026 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	62	0	0	0	0	0	0	7
Svr Tstorm	193	0	0	0	0	0	0	2
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: 246 Verified:  84 [34.1%]
Polygon Size Versus County Size            [33.5%]
Average Perimeter Ratio                    [30.4%]
Percentage of Warned Area Verified (15km)  [18.3%]
Average Storm Based Warning Size           [1690 sq km]
Probability of Detection(higher is better) [0.72]
False Alarm Ratio (lower is better)        [0.66]
Critical Success Index (higher is better)  [0.30]

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