IEM Daily Bulletin for Sep 3 2025
daryl herzmann
Iowa Environmental Mesonet Daily Bulletin for 03 September 2025
News
No news is good newsIEM Code Pushes <repo,branch> on Github
| Timestamp | Repository | Message | Link |
|---|---|---|---|
| Sep 2 8:13 AM | iem,main | ⚡️ Prefer PRISM for climodat regional averages | Link |
| Sep 2 8:50 AM | iem,main | 📝 Sundry updates and coverage improvements | Link |
| Sep 2 8:53 AM | iem,main | 🐛 Add additional row for more years | Link |
| Sep 2 1:07 PM | iem,main | 🐛 Use correct navigation for t_p | Link |
| Sep 2 1:25 PM | iem,main | ⏪️ Stop assuming zero | Link |
| Sep 2 1:26 PM | iem,main | 📝 Sundry updates and PRISM800 rectifying | Link |
| Sep 2 10:30 AM | pyiem,main | 🔥 Remove pyiem.prism per previous announcement | Link |
| Sep 2 10:33 AM | pyiem,main | 🚚 Make PRISM grid nav default to 800m variant | Link |
| Sep 2 8:43 AM | iem-database,main | ✅ Add more HADS testing data | Link |
| Sep 2 8:43 AM | iem-database,main | ⬆️ Update ruff | Link |
Daily Feature
Hourly Temps below 60°F
Date: 02 Sep 05:22 AM
Votes: Good: 9
Bad: 1 Abstain: 0
Temperatures this fine Tuesday morning are in the 50s as our recent stretch of pleasant late summer / early fall weather continues. The featured chart presents the hourly frequency of having a sub 60°F temperature for Des Moines partitioned by ISO week of the year. For the first week of September, such cool temperatures are still mostly relegated to the overnight hours. In takes until mid October until such temperatures are more common than not during the afternoon hours. The forecast for the remainder of this week looks to continue the very pleasant temperatures.
The featured media can be generated on-demand here
.NWS Watch/Warning Summary for 12 AM 2 Sep 2025 - 12 AM 3 Sep 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 | 21 | 0 | 0 | 0 | 0 | 0 | 3 | 0 |
| Flash Flood | 10 | 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: 21 Verified: 5 [23.8%] Polygon Size Versus County Size [13.4%] Average Perimeter Ratio [9.8%] Percentage of Warned Area Verified (15km) [11.6%] Average Storm Based Warning Size [843 sq km] Probability of Detection(higher is better) [0.36] False Alarm Ratio (lower is better) [0.76] Critical Success Index (higher is better) [0.17]