IEM Daily Bulletin for Sep 20 2025
daryl herzmann
Iowa Environmental Mesonet Daily Bulletin for 20 September 2025
News
No news is good newsIEM Code Pushes <repo,branch> on Github
| Timestamp | Repository | Message | Link |
|---|---|---|---|
| Sep 19 9:30 AM | iem,main | ✨ Finally implement conus option for autoplot 90 https://mesonet.agron.iastate.edu/plotting/auto/?q=90 |
Link |
| Sep 19 9:33 AM | iem,main | 📝 Sundry updates per log review | Link |
| Sep 19 8:04 AM | pywwa,main | ⬆️ Update ruff | Link |
| Sep 19 8:09 AM | pywwa,main | 🐛 Address log level bugs | Link |
| Sep 19 12:03 PM | iem-database,main | ✅ Bring NCEI91 network to testing data | Link |
| Sep 19 12:03 PM | iem-database,main | ⬆️ Update ruff | Link |
Daily Feature
Daily Four Inch Soil Temps
Date: 19 Sep 05:30 AM
Votes: Good: 11
Bad: 0 Abstain: 0
With harvest season underway, it is a good time to check in on four inch depth soil temperatures as provided by the ISU Soil Moisture station at the ISU Farm just west of Ames. The featured chart presents the range (tan area) of average daily four inch depth soil temperatures with the 25th to 75th percentile values highlighted in green, a simple and smoothed average shown in black along with the 2025 obs in red. This September has seen quite the range of values with the month starting off with rather chilly soil temperatures below 60°F and then quickly reversing to a value near 80°F. Climatology will quickly take a firm hold with soil temperatures dropping during October as decreasing humidity levels and decreasing solar inputs allow for more net cooling of the near surface soil.
The featured media can be generated on-demand here
.NWS Watch/Warning Summary for 12 AM 19 Sep 2025 - 12 AM 20 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 | 48 | 0 | 2 | 0 | 0 | 0 | 0 | 1 |
| Flash Flood | 18 | 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: 48 Verified: 17 [35.4%] Polygon Size Versus County Size [9.7%] Average Perimeter Ratio [23.3%] Percentage of Warned Area Verified (15km) [22.8%] Average Storm Based Warning Size [736 sq km] Probability of Detection(higher is better) [0.70] False Alarm Ratio (lower is better) [0.65] Critical Success Index (higher is better) [0.31]