Right now
The most recent data we hold from NOAA arrived 8 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
6 other detections within 20 km in the last 24 hours, the nearest <1 km from here.
This alert expired on 22 July 2026 at 01:00 UTC. It is kept here as a record.
It is the 8th strongest of the 221 detections recorded within 20 km of this point since 11 March 2026. The last comparable one was on 18 July 2026. 8 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Tornado Watch issued July 21 at 2:07PM EDT until July 21 at 9:00PM EDT by NWS Mount Holly NJ
Urban PEI: 39,403 within a heuristic 50 km radius; not unique people.
Nearby, since 11 March 2026
- August 27, 2026 · score 34 · 0.0 km
- August 8, 2026 · score 34 · 0.0 km
- July 22, 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.
This is our versioned heuristic index, not source severity or a calibrated probability. Urban PEI does not count unique people.
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 |
| Legacy data-support index | 0.80/1 |
| Coordinates | 39.0000, -75.5000 |
| Nearest City | Dover (18 km) |
| Urban exposure index (PEI) | 39.4K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-21T18:07:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Tornado Watch_noaa_urn:oid:2.49.0.1.840.0.d71910e7beffdd578bf99f6c18701ce9 |
Physical priority index · v1. Heuristic priority, not calibrated probability, predictive accuracy or damage. The legacy data-support index combines assigned source support and field availability. Urban PEI is distance-weighted and does not count unique people; zero does not establish that nobody is present. Model cards.
Source and revision timeline
Source: noaa. Occurrence: 2026-07-21T18:07:00.000Z.
First archived: 2026-07-21T18:43:00.084Z. Material modification: not recorded.
Retained revisions are prospective; earlier versions may be unavailable. No revision entry does not prove that a record never changed.
Score Breakdown
Technical Details
| Event | Tornado Watch |
| Urgency | Future |
| Certainty | Possible |
| AreaDesc | 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 Sandy Hook to Manasquan Inlet NJ out 20 NM; 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; New Castle, DE; Atlantic, NJ; Burlington, NJ; Camden, NJ; Cape May, NJ; Cumberland, NJ; Gloucester, NJ; Hunterdon, NJ; Mercer, NJ; Middlesex, NJ; Monmouth, NJ; Morris, NJ; Ocean, NJ; Salem, NJ; Somerset, NJ; Sussex, NJ; Warren, NJ; Berks, PA; Bucks, PA; Carbon, PA; Chester, PA; Delaware, PA; Lehigh, PA; Monroe, PA; Montgomery, PA; Northampton, PA; Philadelphia, PA |
| Headline | Tornado Watch issued July 21 at 2:07PM EDT until July 21 at 9:00PM EDT by NWS Mount Holly NJ |
| Expires | 2026-07-21T21:00:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | false |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.d71910e7beffdd578bf99f6c18701ce92d9d1707.002.1","noaa_urn:oid:2.49.0.1.840.0.d71910e7beffdd578bf99f6c18701ce92d9d1707.001.1"] |
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.
Review the area, threshold and delivery channel in your account.
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