IEM Daily Bulletin for Dec 30 2025

[daryl herzmann]

Iowa Environmental Mesonet Daily Bulletin for 30 December 2025

News

No news is good news

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Daily Feature

'25-'26 Winter Storm #9
Date: 29 Dec 07:44 AM
Votes: Good: 12   Bad: 1 Abstain: 0

Much like how a major winter storm impacted travel on the weekend following Thanksgiving, a significant winter storm has done the same following Christmas. The featured map presents a smoothed analysis of available snowfall reports from the NWS and CoCoRaHS along with counties under a Blizzard Warning for the event and Snow Squall Warning polygons issued Sunday by the NWS. As with the previous winter storm, snowfall totals were not all that heavy, but the rapidly changing conditions and strong winds created for dangerous travel conditions. Travel remains difficult this Monday morning with ongoing blowing snow and some very brief snow showers. Interstate 35 remains closed, at this time, north of Ames to near Mason City. The good news is that sunshine is in the forecast this week, which after a prolonged period of fog will be a very welcome sight and help mel t away the ice from roadways.

NWS Watch/Warning Summary for 12 AM 29 Dec 2025 - 12 AM 30 Dec 2025 CST

	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	0	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            [47.4%]
Average Perimeter Ratio                    [10.1%]
Percentage of Warned Area Verified (15km)  [0.0%]
Average Storm Based Warning Size           [2652 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]