This alert expired on 28 May 2026 at 17:00 UTC. It is kept here as a record.
It is the 4th strongest of the 105 detections recorded within 20 km of this point since 16 March 2026. Another comparable one was recorded here earlier the same day. 24 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued May 28 at 11:40AM CDT until May 28 at 12:00PM CDT by NWS New Orleans LA
An estimated 866,520 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 22, 2026 · score 48 · 4.2 km
- July 7, 2026 · score 48 · 6.8 km
- June 7, 2026 · score 48 · 7.7 km
How we know
Confirmed by 3 independent sources, including NOAA.
Our own score for this event is 48 out of 100, at 90 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Event Data
| Type | Severe weather |
| Severity | medium |
| Calamity Score (ours) | 48 / 100 |
| Our confidence | 90% |
| Coordinates | 30.2233, -89.9250 |
| Nearest City | Slidell (15 km) |
| Population Exposed | 866.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-05-28T16:40:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.a13bec7c69c4f6160bc61b255dfb2990d663661e.001.1 |
Score Breakdown
Technical Details
| Event | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Lake Pontchartrain |
| Headline | Special Marine Warning issued May 28 at 11:40AM CDT until May 28 at 12:00PM CDT by NWS New Orleans LA |
| Expires | 2026-05-28T12:00:00-05:00 |
| SenderName | NWS New Orleans LA |
| HasExactCoords | true |
| Iem TypeSummary | W |
| Iem City | 7 SSW Eden Isle |
| Iem County | GMZ531 |
| Iem State | LA |
| Iem Wfo | LIX |
| Iem Remark | Broadcast media relayed picture of waterspout over Lake Pontchartrain near Irish Bayou. |
| MergedSources | [{"id":"iem_W_30.220_-89.880_1779971880000","source":"iem","severity":"low","severityValue":25,"timestamp":1779971880000,"latitude":30.22,"longitude":-89.88},{"id":"iem_W_30.150_-89.850_1779970200000","source":"iem","severity":"low","severityValue":25,"timestamp":1779970200000,"latitude":30.15,"longitude":-89.85}] |
Safety Information
Always follow official guidance from your local emergency management agency. This platform provides scientific monitoring data and is not a substitute for official warnings. If you are in immediate danger, contact your local emergency number.
Series begins 10 February 2026. Comparisons refer to that period only. Collection gap: 14-26 August 2026.
This data is aggregated algorithmically from scientific sources. Not a replacement for official emergency warnings.
Calamity.live data shows a weather event with CalamityScore 48/100, near Slidell (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 188 scientific monitoring sources.