This alert expired on 22 July 2026 at 02:00 UTC. It is kept here as a record.
It is the 8th strongest of the 237 detections recorded within 20 km of this point since 11 March 2026. The last comparable one was on 21 July 2026. 13 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Tornado Watch issued July 21 at 8:46PM EDT until July 21 at 9:00PM EDT by NWS Mount Holly NJ
An estimated 39,403 people live within 50 km of this point.
Nearby, since 11 March 2026
- August 27, 2026 · score 34 · 0.0 km
- August 8, 2026 · score 34 · 0.0 km
- July 21, 2026 · score 46 · 0.0 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 46 out of 100, at 80 % confidence.
The score is ours, computed from intensity, exposed population and local history — not the source’s.
Computed under scoring rules v1. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 46 / 100 |
| Our confidence | 80% |
| Coordinates | 39.0000, -75.5000 |
| Nearest City | Dover (18 km) |
| Population Exposed | 39.4K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-22T00:46:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Tornado Watch_noaa_urn:oid:2.49.0.1.840.0.01cc9f4ba47463100f70886203ca4647 |
Score Breakdown
Technical Details
| Event | Tornado Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | New Castle, DE; Atlantic, NJ; Burlington, NJ; Camden, NJ; Cape May, NJ; Cumberland, NJ; Gloucester, NJ; Ocean, NJ; Salem, NJ; Delaware Bay waters north of East Point NJ to Slaughter Beach DE; Delaware Bay waters south of East Point NJ to Slaughter Beach DE; Coastal waters from Manasquan Inlet to Little Egg Inlet NJ out 20 NM; Coastal waters from Little Egg Inlet to Great Egg Inlet NJ out 20 NM; Coastal waters from Great Egg Inlet to Cape May NJ out 20 NM; Coastal waters from Cape May NJ to Cape Henlopen DE out 20 NM |
| Headline | Tornado Watch issued July 21 at 8:46PM EDT until July 21 at 9:00PM EDT by NWS Mount Holly NJ |
| Expires | 2026-07-21T22:00:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | false |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.01cc9f4ba47463100f70886203ca4647cb21162b.001.1","noaa_urn:oid:2.49.0.1.840.0.01cc9f4ba47463100f70886203ca4647cb21162b.002.1"] |
Safety Information
If a tornado warning is issued: go to a basement or an interior room on the lowest floor, away from windows. A vehicle and a mobile home are not shelter. Cover your head and neck. Wait for the official all-clear before going outside, and watch for downed power lines and gas leaks afterwards.
Series begins 8 March 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.
Want to know when something happens near Dover?
Calamity.live data shows a weather event with CalamityScore 46/100, near Dover (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.