This alert expired on 27 August 2026 at 22:47 UTC. It is kept here as a record.
It is the 80th strongest of the 121 detections recorded within 20 km of this point since 17 March 2026. Another comparable one was recorded here earlier the same day.
What the source measured
NOAA reported: Flash Flood Warning issued August 27 at 6:37PM EDT until August 27 at 6:45PM EDT by NWS Mount Holly NJ
An estimated 540,541 people live within 50 km of this point.
Nearby, since 17 March 2026
- June 6, 2026 · score 48 · 7.1 km
- July 29, 2026 · score 37 · 7.6 km
- July 28, 2026 · score 37 · 7.6 km
How we know
Confirmed by 4 independent sources, including NOAA.
Our own score for this event is 41 out of 100, at 89 % 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) | 41 / 100 |
| Our confidence | 89% |
| Coordinates | 40.4794, -75.4782 |
| Nearest City | Allentown (15 km) |
| Population Exposed | 540.5K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-27T22:37:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Flash Flood Warning_noaa_urn:oid:2.49.0.1.840.0.0f60a1da2514ecd231d1bbd6c8a7fc37 |
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Camden, NJ; Delaware, PA; Philadelphia, PA; Warren, NJ; Northampton, PA; Lycoming, PA; Sullivan, PA and 2 more areas |
| Headline | Flash Flood Warning issued August 27 at 6:37PM EDT until August 27 at 6:45PM EDT by NWS Mount Holly NJ |
| Expires | 2026-08-27T18:47:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | true |
| MergedCount | 5 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.0f60a1da2514ecd231d1bbd6c8a7fc37f4d63c0c.001.1","noaa_urn:oid:2.49.0.1.840.0.2595b80571bbec6f122b69b9d1b6e6b250ed3bd9.001.1","noaa_urn:oid:2.49.0.1.840.0.13217a081fd3e25fe08afd17842cdac94a58432b.001.1","noaa_urn:oid:2.49.0.1.840.0.6fc361e9a5c586ca4723b80f4776a7c57e2c25f0.001.1","noaa_urn:oid:2.49.0.1.840.0.6f7fd96026376c3ea17015cf1600408b58a52446.001.1"] |
| Iem TypeSummary | R |
| Iem Magnitude | 1.95 |
| Iem Unit | Inch |
| Iem City | Phillipsburg |
| Iem County | Warren |
| Iem State | NJ |
| Iem Wfo | PHI |
| Iem Remark | CO-OP Observer station ESTN4 Phillipsburg. |
| MergedSources | [{"id":"iem_R_40.680_-74.900_1787862300000","source":"iem","severity":"low","severityValue":25,"timestamp":1787862300000,"latitude":40.68,"longitude":-74.9},{"id":"iem_F_40.230_-75.640_1787866200000","source":"iem","severity":"low","severityValue":25,"timestamp":1787866200000,"latitude":40.23,"longitude":-75.64},{"id":"iem_R_40.700_-75.200_1787859000000","source":"iem","severity":"low","severityValue":25,"timestamp":1787859000000,"latitude":40.7,"longitude":-75.2}] |
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 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.
Want to know when something happens near Allentown?
Calamity.live data shows a weather event with CalamityScore 41/100, near Allentown (United States), based on data from noaa. Source: Calamity.live, a platform aggregating real-time data from 185 scientific monitoring sources.