Right now
The most recent data we hold from NOAA arrived 35 minutes ago, and this point is not in it. We record detections, not passes: an absence is not proof that nothing is there.
5 other detections within 20 km in the last 24 hours, the nearest <1 km from here.
This alert expired on 17 September 2026 at 05:30 UTC. It is kept here as a record.
It is the 21st strongest of the 49 detections recorded within 20 km of this point since 23 June 2026. Another comparable one was recorded here earlier the same day. 9 more were recorded here in the fortnight before it.
What the source measured
NOAA reported: Flash Flood Warning issued September 16 at 9:27PM MST until September 16 at 10:30PM MST by NWS Tucson AZ
Urban PEI: 791,006 within a heuristic 50 km radius; not unique people.
Nearby, since 23 June 2026
- September 15, 2026 · score 41 · 4.9 km
- August 4, 2026 · score 48 · 5.0 km
- September 17, 2026 · score 41 · 5.4 km
How we know
2 recorded sources include NOAA; independence is not established by this count.
Our own score for this event is 41 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 v5. Rows carrying other versions were judged by different rules and are not directly comparable.
Event Data
| Type | Severe Weather |
| Severity | Medium |
| Calamity Score (ours) | 41 / 100 |
| Legacy data-support index | 0.86/1 |
| Coordinates | 32.3450, -111.3007 |
| Nearest City | Marana (12 km) |
| Urban exposure index (PEI) | 791.0K within 50 km |
| Impact Tier | significant |
| Timestamp | 2026-09-17T04:27:00.000Z |
| Source | https://api.weather.gov/alerts/urn%3Aoid%3A2.49.0.1.840.0.e561921f678cb766fa340ee4ee8a46ac533cd3c6.001.1 |
Physical priority index · v5. 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: 2026-09-17T04:27:00.000Z.
First archived: 2026-09-17T04:32:29.277Z. Material modification: not recorded.
Retained revisions are prospective; earlier versions may be unavailable. No revision entry does not prove that a record never changed.
2026-09-17T04:54:22.170Z · data_change
Index 41 → 41; severity medium → medium; version 5 → 5.
Score Breakdown
Technical Details
| Event | Flash Flood Warning |
| Urgency | Immediate |
| Certainty | Likely |
| AreaDesc | Pima, AZ; Pinal, AZ; Pima, AZ |
| Headline | Flash Flood Warning issued September 16 at 9:27PM MST until September 16 at 10:30PM MST by NWS Tucson AZ |
| Expires | 2026-09-16T22:30:00-07:00 |
| SenderName | NWS Tucson AZ |
| HasExactCoords | true |
| MergedCount | 2 |
| MergedIds | ["noaa_urn:oid:2.49.0.1.840.0.e561921f678cb766fa340ee4ee8a46ac533cd3c6.001.1","noaa_urn:oid:2.49.0.1.840.0.90521e1a71ddbbc5abf80ef0b0aeb65ed78dd6ca.001.1"] |
| Iem TypeSummary | F |
| Iem City | 8 SW Oro Valley |
| Iem County | Pima |
| Iem State | AZ |
| Iem Wfo | TWC |
| Iem Remark | Stalled vehicle due to flash flooding. |
| MergedSources | [{"id":"iem_R_32.330_-111.030_1789607460000","source":"iem","severity":"low","severityValue":25,"timestamp":1789607460000,"latitude":32.33,"longitude":-111.03},{"id":"iem_R_32.200_-111.170_1789606680000","source":"iem","severity":"low","severityValue":25,"timestamp":1789606680000,"latitude":32.2,"longitude":-111.17},{"id":"iem_R_32.330_-111.030_1789607940000","source":"iem","severity":"low","severityValue":25,"timestamp":1789607940000,"latitude":32.33,"longitude":-111.03},{"id":"iem_R_32.210_-110.840_1789608240000","source":"iem","severity":"low","severityValue":25,"timestamp":1789608240000,"latitude":32.21,"longitude":-110.84},{"id":"iem_F_32.160_-111.210_1789609620000","source":"iem","severity":"low","severityValue":25,"timestamp":1789609620000,"latitude":32.16,"longitude":-111.21},{"id":"iem_F_32.320_-111.050_1789608360000","source":"iem","severity":"low","severityValue":25,"timestamp":1789608360000,"latitude":32.32,"longitude":-111.05}] |
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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