Right now
The most recent data we hold from NOAA arrived 3 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 4 August 2026 at 20:45 UTC. It is kept here as a record.
No stronger detection stands among the 32 recorded within 20 km of this point since 8 March 2026 — 19 others scored the same. Another comparable one was recorded here earlier the same day. 2 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Special Marine Warning issued August 4 at 3:43PM EDT until August 4 at 4:45PM EDT by NWS Jacksonville FL
Urban PEI: 1,128,316 within a heuristic 50 km radius; not unique people.
Nearby, since 8 March 2026
- June 17, 2026 · score 46 · 7.1 km
- June 15, 2026 · score 52 · 7.7 km
- July 15, 2026 · score 52 · 7.8 km
How we know
2 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 52 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) | 52 / 100 |
| Legacy data-support index | 0.86/1 |
| Coordinates | 30.3514, -81.1600 |
| Nearest City | Jacksonville Beach (23 km) |
| Urban exposure index (PEI) | 1.1M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-04T19:43:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.f5f9fc3e043eab50eeb803288bd103165b65a942.001.1 |
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: 2026-08-04T19:43:00.000Z.
First archived: 2026-08-04T20:43:21.409Z. 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 | Special Marine Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Coastal waters from Fernandina Beach to St. Augustine FL out 20 NM; Waters from Fernandina Beach to St. Augustine FL from 20 to 60 NM |
| Headline | Special Marine Warning issued August 4 at 3:43PM EDT until August 4 at 4:45PM EDT by NWS Jacksonville FL |
| Expires | 2026-08-04T16:45:00-04:00 |
| SenderName | NWS Jacksonville FL |
| HasExactCoords | true |
| Iem TypeSummary | G |
| Iem Magnitude | 41 |
| Iem Unit | MPH |
| Iem City | 2 NE Jacksonville Inter |
| Iem County | Duval |
| Iem State | FL |
| Iem Wfo | JAX |
| Iem Remark | ASOS station KJAX Jacksonville Intl Airport. |
| MergedSources | [{"id":"iem_G_30.500_-81.680_1785867480000","source":"iem","severity":"low","severityValue":25,"timestamp":1785867480000,"latitude":30.5,"longitude":-81.68}] |
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 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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