IEM Daily Bulletin for Oct 10 2025

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 10 October 2025

News

No news is good news

IEM Code Pushes <repo,branch> on Github

Timestamp	Repository	Message	Link
No code commits found in previous 24 Hours

Daily Feature

90% of Monthly Total in One Day
Date: 09 Oct 05:30 AM
Votes: Good: 10   Bad: 0 Abstain: 0

For the month of September, the Storm Lake (NW Iowa) NWS COOP station reported just two daily rainfalls with 0.04" on the 10th and 0.42" on the 19th. So roughly 90% of the monthly total fell on just one day. The featured chart looks into the frequency of that happening with the most recent yearly occurrence shown above each bar. While generally rare, these events are most frequent during the colder half of the year when precipitation totals are lower and more easily comprised of just one big event. This situation is much more difficult during the summer months as rainfall events are more frequent and heavy rainfall events less isolated.

The featured media can be generated on-demand here

.

NWS Watch/Warning Summary for 12 AM 9 Oct 2025 - 12 AM 10 Oct 2025 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	0	0	0	0	0	0	0	0
Svr Tstorm	1	0	0	0	0	0	0	0
Flash Flood	9	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:   1 Verified:   0 [0.0%]
Polygon Size Versus County Size            [12.0%]
Average Perimeter Ratio                    [0.0%]
Percentage of Warned Area Verified (15km)  [0.0%]
Average Storm Based Warning Size           [1386 sq km]
Probability of Detection(higher is better) [0.00]
False Alarm Ratio (lower is better)        [1.00]
Critical Success Index (higher is better)  [0.00]