Historical events SR-5
A standing catalog of past hazardous events — frequency, magnitude, and spatial distribution — including hazard chains where one event triggered or worsened another. Distinct from VerificationRecord, which is a forecast-vs-observed note on one specific resolved alert.
Event catalog — Analamanga
| Date | Hazard | Magnitude | Spatial extent | Frequency (10yr) |
|---|---|---|---|---|
| 2026-06 | Flood | 6.3m peak river level | 3 districts | 4th occurrence |
| 2025-01 | Cyclone + Flood | Category 3 / 5.8m | 5 districts | 2nd combined occurrence |
| 2023-11 | Drought | SPI -1.8 | Region-wide | 3rd occurrence |
Hazard chain — January 2025 event
- 2025-01-14 — Cyclone makes landfall (Category 3)
- 2025-01-15 — Heavy rainfall from cyclone remnants (cascading)
- 2025-01-16 — River levels breach Severe threshold (compound flood event)
- 2025-01-19 — Localized landslide reported in Atsinanana (cascading)
Recording the chain — not just each event in isolation — is what lets an Analyst recognize a compounding sequence early next time.
Sources: BNGRC post-event reports (2023–2026) · GloFAS historical archive ·
Regional cyclone outlook feed archive.