IEM Daily Bulletin for Oct 29 2025

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 29 October 2025

News

No news is good news

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Daily Feature

October Overcast
Date: 28 Oct 05:30 AM
Votes: Good: 10   Bad: 0 Abstain: 0

Overcast skies and rainy conditions look to dominate much of Tuesday. The featured chart looks into the percentage of hourly observations from the Des Moines airport that have reported overcast sky conditions. The top panel plots the 2025 monthly observations along with a period of record climatology. The bottom panel plots the yearly percentages for each October. The 2025 value comes in close to climatology. Of course, looking forward you can see climatology increases significantly into the winter months with December holding the highest frequencies at just under 50%. It is one of the difficult aspects of the winter season, the amount of cloudy weather!

The featured media can be generated on-demand here

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NWS Watch/Warning Summary for 12 AM 28 Oct 2025 - 12 AM 29 Oct 2025 CDT

	Summary		By WFO					Watches
Type	US	IA	ARX	DVN	DMX	OAX	FSD	US
Tornado	5	0	0	0	0	0	0	1
Svr Tstorm	18	0	0	0	0	0	0	0
Flash Flood	1	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:  23 Verified:   2 [8.7%]
Polygon Size Versus County Size            [16.1%]
Average Perimeter Ratio                    [13.4%]
Percentage of Warned Area Verified (15km)  [4.1%]
Average Storm Based Warning Size           [893 sq km]
Probability of Detection(higher is better) [0.33]
False Alarm Ratio (lower is better)        [0.91]
Critical Success Index (higher is better)  [0.07]