Rainfall | Center for Urban Water, Sri Lanka

Rainfall

Rainfall inputs are made by integrating gauge measurements, satellite rainfall maps and numerical weather forecast information. The programme utilize currently available gauge data until the new gauges will be installed and expand as new data sources become availabe. 

Rain Gauges

CUrW has deployed a number of IoT based rain gauges and their observations are directly coupled to simulation models through CUrW IoT platform. These data are also available to public.

Currently the deployment is in the study phase where different types of rain gaugesand communication protocols are being tested.

Numerical Weather Forecasts

The center carries out numerical weather forecasts for Sri Lanka focussing on the Western Reigion using the WRF model. The final domain resolution is 3km and the forecasts are carried out automatically. This is a work in progress and at present we are comparing the forecasts with real time satellite rain observations to select the best fit parameterisation for the current weather sytem. The bias correction of this forecasts will be carried out with the gauge observations once become available. 

Rainfall from Observations

The GS map pf Japan Aerospace Agency (Jaxa)  provides an update of rainfall information of  rainfall distributions at 10 km resolutionevery 30 min.. At present these data are availale at near real time. CUrW runs a number of weather forecast models in real time and satellite based observations are useful in selecting an apropriate forecast.