Catchment rain, not city rain
JalaNet queries a numerical weather model at each dam's coordinates, so the figures describe the catchment feeding the reservoir — not the nearest town. Heavy rain over the upper catchment reaches the dam within hours even if the downstream district stays dry.
The dashboard shows two totals: the next 24 hours and the next 72 hours. The 24 h number drives the immediate alert; the 72 h number tells you whether operators will need to keep releasing water after the current spell.
Intensity beats total
100 mm spread over three days is usually absorbed by soil and vegetation. The same 100 mm in six hours produces surface runoff, sharp inflow spikes and landslide conditions. That is why the risk engine weighs rainfall intensity and antecedent (already-fallen) rain separately from bare totals.
Forecasts are probabilities
Model rainfall over the Western Ghats is notoriously hard: orographic lift concentrates rain onto narrow ridge lines that a coarse grid smooths out. Treat forecast values as an order of magnitude, refreshed every 15 minutes, and always defer to IMD warnings and district administration instructions.