Sri Lanka · observational tracker · Asia/Colombo

Rainfall & rivers

Choose a river system, then a measuring point. The dashboard pairs modelled rainfall at that gauge’s exact coordinates with its measured river-level history.

River systems
Outline: geoBoundaries gbOpen (OSM/Wambacher, ODbL). Rivers: HydroRIVERS / HydroSHEDS via nuuuwan/lk_rivers. No external basemap tiles are used.
Rainfall-only city or custom coordinates
Loading river observations…

Choose a gauge

No default gauge is implied.
River selection filters context; a gauge selection loads its exact rainfall coordinates.

Coordinated daily record

Rainfall above · river level below · shared LKT date axis
Select a gauge, or load a rainfall-only location.
Modelled daily rainfall Measured daily river peak Gaps stay unconnected

Rainfall is modelled. Open-Meteo provides ECMWF ERA5/IFS coordinate-based estimates, not rain-gauge measurements. The newest days may be preliminary.

River levels are measured gauge observations. Current readings come from the Sri Lanka Irrigation Department’s official ArcGIS dashboard. Earlier readings come from the community-maintained mirror. Values use the gauge datum, can be negative, and are never interpolated.

Thambuththegama uses the official coordinate in the Irrigation Department’s Hydrological Annual 2021/22. This public tracker is observational—not a forecast, flood-extent map, certification source, or nearest-gauge recommendation.