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.
Nothing else has been detected within 20 km in the last 24 hours.
This alert expired on 3 July 2026 at 23:45 UTC. It is kept here as a record.
It is the 6th strongest of the 68 detections recorded within 20 km of this point since 26 March 2026. Another comparable one was recorded here earlier the same day. 4 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Severe Thunderstorm Warning issued July 3 at 6:45PM EDT until July 3 at 7:45PM EDT by NWS Detroit/Pontiac MI
Urban PEI: 428,653 within a heuristic 50 km radius; not unique people.
Nearby, since 26 March 2026
- July 28, 2026 · score 43 · 11.9 km
- March 26, 2026 · score 43 · 14.9 km
- September 3, 2026 · score 37 · 16.0 km
How we know
6 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 43 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) | 43 / 100 |
| Legacy data-support index | 0.89/1 |
| Coordinates | 41.8397, -83.6148 |
| Nearest City | Sylvania (15 km) |
| Urban exposure index (PEI) | 428.7K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-07-03T22:45:00.000Z |
| Source | https://api.weather.gov/alerts/merged_Severe Thunderstorm Warning_noaa_urn:oid:2.49.0.1.840.0.18d36485b3a70629bc67c1ac44e0f3ca |
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: 2026-07-03T22:45:00.000Z.
First archived: 2026-07-03T22:47:20.191Z. 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 | Severe Thunderstorm Warning |
| Urgency | Immediate |
| Certainty | Observed |
| AreaDesc | Lapeer, MI; Erie, OH; Ottawa, OH; Sandusky, OH; Seneca, OH; Wood, OH; Macomb, MI and 4 more areas |
| Headline | Severe Thunderstorm Warning issued July 3 at 6:45PM EDT until July 3 at 7:45PM EDT by NWS Detroit/Pontiac MI |
| Expires | 2026-07-03T19:45:00-04:00 |
| SenderName | NWS Detroit/Pontiac MI |
| HasExactCoords | true |
| MergedCount | 7 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.18d36485b3a70629bc67c1ac44e0f3ca5b7d7fa8.001.1","noaa_urn:oid:2.49.0.1.840.0.2d897939d3bd95e35fe4c2fa9f841d405c3dadd0.001.1","noaa_urn:oid:2.49.0.1.840.0.3ffb2f713985327cfac364fe3dfd8db404af5150.001.1","noaa_urn:oid:2.49.0.1.840.0.0fbc75e742388ca9bf341f64378400d83218eb22.001.1","noaa_urn:oid:2.49.0.1.840.0.94c03b0a6df22330daac3d76bbfc016094ca25f1.002.1","noaa_urn:oid:2.49.0.1.840.0.f8dbdff3df6450fdc77dbe7109e62688aa435529.001.1","noaa_urn:oid:2.49.0.1.840.0.135b795dd3c80dc99e1fd8f5c71df0716d07dc29.001.1"] |
| Iem TypeSummary | D |
| Iem City | 1 N Dexter |
| Iem County | Washtenaw |
| Iem State | MI |
| Iem Wfo | DTX |
| Iem Remark | Report of multiple trees on roadway around Mast Rd and Joy Rd |
| MergedSources | [{"id":"iem_D_42.150_-84.020_1783115400000","source":"iem","severity":"low","severityValue":25,"timestamp":1783115400000,"latitude":42.15,"longitude":-84.02},{"id":"iem_G_42.240_-83.530_1783115940000","source":"iem","severity":"low","severityValue":25,"timestamp":1783115940000,"latitude":42.24,"longitude":-83.53},{"id":"iem_G_41.940_-83.430_1783115580000","source":"iem","severity":"low","severityValue":25,"timestamp":1783115580000,"latitude":41.94,"longitude":-83.43},{"id":"iem_D_42.320_-84.020_1783113960000","source":"iem","severity":"low","severityValue":25,"timestamp":1783113960000,"latitude":42.32,"longitude":-84.02},{"id":"iem_D_42.340_-83.880_1783114680000","source":"iem","severity":"low","severityValue":25,"timestamp":1783114680000,"latitude":42.34,"longitude":-83.88}] |
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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