IEM Daily Bulletin for Nov 10 2025
daryl herzmann
Iowa Environmental Mesonet Daily Bulletin for 10 November 2025
News
No news is good newsIEM Code Pushes <repo,branch> on Github
| Timestamp | Repository | Message | Link |
|---|---|---|---|
| Nov 9 10:40 AM | iem,main | 📝 Add winter2526 as a thing | Link |
| Nov 9 11:02 AM | iem,main | 🐛 Fix logic | Link |
Daily Feature
'25-'26 Winter Storm #1
Date: 09 Nov 10:32 AM
Votes: Good: 5
Bad: 0 Abstain: 0
The first snowfall of the season for Iowa brought a number of inches of snowfall over northwestern Iowa on Saturday. These early season snowfalls tend to be difficult to measure and report as soil temperatures are well above freezing yet. This event also mostly fell during the daytime hours, so pavement temperatures where plenty warm to melt much of the falling snow as well. So the featured map is a bit rough, but the general pattern shown fits available reports over the past 24 hours. The largest total reported was around five inches near Spencer. The first significant cold air of the season also arrived for the weekend with air temperatures and wind chill values both well below freezing. And finally for accounting, the IEM produces these snowfall maps derived from available NWS COOP, Local Storm Reports, and CoCoRaHS observations when snowfall totals of at least two inches are reported and/or significant winter weather impacts are observed. The IEM has been generating these maps for 16 winter seasons now! These maps are generated from Autoplot 207, but get some manual quality control to help produce a refined analysis.
The featured media can be generated on-demand here
.NWS Watch/Warning Summary for 12 AM 9 Nov 2025 - 12 AM 10 Nov 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 | 19 | 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: 19 Verified: 10 [52.6%] Polygon Size Versus County Size [25.6%] Average Perimeter Ratio [13.1%] Percentage of Warned Area Verified (15km) [42.2%] Average Storm Based Warning Size [1366 sq km] Probability of Detection(higher is better) [0.97] False Alarm Ratio (lower is better) [0.47] Critical Success Index (higher is better) [0.52]