Baixa flooding anticipated through underground runoff observation
Over 60 minutes, 16 mm of rain fell on central Lisbon — about 27% of the full May historical average, per IPMA. greenmetrics.ai radar sensors detected the abrupt underground level change minutes before it emerged at street level.
How it unfolded
- 16:50
Rainfall onset. IPMA records 16 mm in one hour — 27% of the full May average.
- 17:25
Radar sensor inside the Av. Almirante Reis drainage conduit records a baseline of 23 cm.
- 17:55
The same radar detects a 10× rise to 216 cm within 30 minutes — an unambiguous signature of critical overflow upstream.
- 17:59
greenmetrics.ai fires an alert to the downstream sensor location at Martim Moniz. Civil protection is notified. Water arrives at street level ~5 minutes later.
- 18:04
Ground truth confirmed: flooding visible at Martim Moniz, exactly where the alert predicted.
Why it matters
This event is the canonical proof of greenmetrics.ai's anticipatory detection capability: a subterranean radar reading converted into actionable surface warning before citizens, traffic, or emergency crews were affected. The sensors are currently being densified to push the lead time from 5 to 15+ minutes.
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