This alert expired on 18 July 2026 at 02:15 UTC. It is kept here as a record.
No stronger detection stands among the 57 recorded within 20 km of this point since 16 March 2026 — 43 others scored the same. Another comparable one was recorded here earlier the same day. 13 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued July 17 at 5:48PM EDT until July 17 at 10:15PM EDT by NWS Peachtree City GA
An estimated 1,817,227 people live within 50 km of this point.
Nearby, since 16 March 2026
- July 4, 2026 · score 52 · 1.4 km
- July 24, 2026 · score 52 · 9.8 km
- July 4, 2026 · score 52 · 9.8 km
How we know
One source: NOAA. Not yet confirmed by a second, independent source.
Our own score for this event is 52 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) | 52 / 100 |
| Our confidence | 80% |
| Coordinates | 33.9519, -84.1908 |
| Nearest City | Norcross (2 km) |
| Population Exposed | 1.8M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-17T21:48:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.937e56fcbd8ad462f2363c822a7e5b3c |
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Forsyth, GA; Gwinnett, GA; DeKalb, GA; Gwinnett, GA; Cherokee, GA; Cobb, GA; DeKalb, GA; Fulton, GA; Gwinnett, GA |
| Headline | Flash Flood Warning issued July 17 at 5:48PM EDT until July 17 at 10:15PM EDT by NWS Peachtree City GA |
| Expires | 2026-07-17T22:15:00-04:00 |
| SenderName | NWS Peachtree City GA |
| HasExactCoords | true |
| MergedCount | 3 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.937e56fcbd8ad462f2363c822a7e5b3c3aff5326.001.1","noaa_urn:oid:2.49.0.1.840.0.234a171d9e2f6f9b1d5ffce2122b05b3453e5ab4.001.1","noaa_urn:oid:2.49.0.1.840.0.0309f21473aa8803dfac0f6d28e7e20d4e38972c.001.1"] |
Safety Information
During flooding: never walk, swim, or drive through floodwaters. Six inches of moving water can knock you down, and one foot of water can sweep away a vehicle. Move to higher ground if waters rise. After flooding, avoid contact with floodwater which may contain sewage, chemicals, or debris. Follow local emergency service guidance.
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 Norcross?
Calamity.live data shows a weather event with CalamityScore 52/100, near Norcross (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.