IEM Daily Bulletin for Mar 17 2025

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 17 March 2025

News

No news is good news

IEM Code Pushes <to branch> on Github

• Mar 16 10:05 AM <main> 🐛 Revert url encoding and address some lint
• Mar 16 10:30 AM <main> Merge pull request #1166 from akrherz/250315-2
  🐛 Revert url encoding and address some lint
• Mar 16 3:24 PM <main> ✨ Add multi-day option to VTEC top10 event counts
  https://mesonet.agron.iastate.edu/plotting/auto/?q=243
• Mar 16 3:35 PM <main> Merge pull request #1167 from akrherz/250316
  ✨ Add multi-day option to VTEC top10 event counts
• Mar 17 6:55 AM <main> 🐛 Fix how window works

Daily Feature

'24-'25 Winter Storm #17
Date: 16 Mar 10:36 AM
Votes: Good: 6   Bad: 0 Abstain: 0

A significant and expansive storm system continues to churn over the Great Lakes region this Sunday morning. This system brought record high temperatures on Friday along with strong winds and severe weather. The backside of the system clipped far southeastern Iowa overnight with a narrow and intense band of snowfall. The featured analysis of available reports show a small area of four plus inches of snow! This snowfall will struggle to survive the day with mid March sunshine typically making quick melting work of snow.

NWS Watch/Warning Summary for 12 AM 16 Mar 2025 - 12 AM 17 Mar 2025 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	47	0	0	0	0	0	0	6
Svr Tstorm	174	0	0	0	0	0	0	1
Flash Flood	13	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: 219 Verified:  92 [42.0%]
Polygon Size Versus County Size            [42.2%]
Average Perimeter Ratio                    [30.8%]
Percentage of Warned Area Verified (15km)  [22.1%]
Average Storm Based Warning Size           [2715 sq km]
Probability of Detection(higher is better) [0.89]
False Alarm Ratio (lower is better)        [0.58]
Critical Success Index (higher is better)  [0.40]