Right now
The most recent data we hold from NOAA arrived 1 minute 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 6 August 2026 at 05:15 UTC. It is kept here as a record.
It is the 3rd strongest of the 274 detections recorded within 20 km of this point since 12 March 2026. The last comparable one was on 5 August 2026. 13 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued August 5 at 9:04PM EDT until August 6 at 1:15AM EDT by NWS Mount Holly NJ
Urban PEI: 3,391,121 within a heuristic 50 km radius; not unique people.
Nearby, since 12 March 2026
- July 21, 2026 · score 46 · 2.4 km
- July 9, 2026 · score 52 · 5.3 km
- August 3, 2026 · score 46 · 5.5 km
How we know
12 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 | 0.90/1 |
| Coordinates | 40.1736, -75.3364 |
| Nearest City | Norristown (6 km) |
| Urban exposure index (PEI) | 3.4M within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-08-06T01:04:00.000Z |
| Source | https://api.weather.gov/alerts/urn:oid:2.49.0.1.840.0.dc38f9afdb9b73b62bd3d4d2f9294221d88eb306.001.1 |
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: 2026-08-06T01:04:00.000Z.
First archived: 2026-08-06T01:26:18.956Z. 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 | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Bucks, PA; Chester, PA; Delaware, PA; Montgomery, PA |
| Headline | Flash Flood Warning issued August 5 at 9:04PM EDT until August 6 at 1:15AM EDT by NWS Mount Holly NJ |
| Expires | 2026-08-06T01:15:00-04:00 |
| SenderName | NWS Mount Holly NJ |
| HasExactCoords | true |
| Iem TypeSummary | R |
| Iem Magnitude | 2.6 |
| Iem Unit | Inch |
| Iem City | 1 S Lima |
| Iem County | Delaware |
| Iem State | PA |
| Iem Wfo | PHI |
| Iem Remark | Mesonet station FW3096 Media. |
| MergedSources | [{"id":"iem_R_39.990_-75.000_1785957300000","source":"iem","severity":"low","severityValue":25,"timestamp":1785957300000,"latitude":39.99,"longitude":-75},{"id":"iem_R_39.790_-75.980_1785960000000","source":"iem","severity":"low","severityValue":25,"timestamp":1785960000000,"latitude":39.79,"longitude":-75.98},{"id":"iem_R_39.770_-75.610_1785974820000","source":"iem","severity":"low","severityValue":25,"timestamp":1785974820000,"latitude":39.77,"longitude":-75.61},{"id":"iem_O_40.200_-74.670_1785960300000","source":"iem","severity":"low","severityValue":25,"timestamp":1785960300000,"latitude":40.2,"longitude":-74.67},{"id":"iem_F_40.300_-75.000_1785957300000","source":"iem","severity":"low","severityValue":25,"timestamp":1785957300000,"latitude":40.3,"longitude":-75},{"id":"iem_R_39.990_-75.000_1785974400000","source":"iem","severity":"low","severityValue":25,"timestamp":1785974400000,"latitude":39.99,"longitude":-75},{"id":"iem_R_40.100_-74.870_1785974880000","source":"iem","severity":"low","severityValue":25,"timestamp":1785974880000,"latitude":40.1,"longitude":-74.87},{"id":"iem_F_40.190_-75.110_1785957000000","source":"iem","severity":"low","severityValue":25,"timestamp":1785957000000,"latitude":40.19,"longitude":-75.11},{"id":"iem_O_39.870_-75.020_1785958800000","source":"iem","severity":"low","severityValue":25,"timestamp":1785958800000,"latitude":39.87,"longitude":-75.02},{"id":"iem_R_40.100_-74.870_1785958080000","source":"iem","severity":"low","severityValue":25,"timestamp":1785958080000,"latitude":40.1,"longitude":-74.87},{"id":"iem_R_39.900_-75.440_1785975000000","source":"iem","severity":"low","severityValue":25,"timestamp":1785975000000,"latitude":39.9,"longitude":-75.44}] |
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.
Review the area, threshold and delivery channel in your account.
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