About this product
ECMWF HRES is the European Centre's operational deterministic forecast — the model forecasters call “the Euro”, and the one widely regarded as the world's most accurate. This site draws it at 0.1°, roughly 11 km, rather than the 0.25° open-data grid most public sites use: about seven times as many grid points, which is the difference between a smooth blob over the Western Ghats and a forecast that knows which side of them the rain falls on.
Colours are the authentic ecCharts tables — the exact ECMWF Magics named colours in ecCharts palette order, on the published HRES level breaks, shaded as discrete bands rather than a smooth ramp. Reproducing that banding is most of what makes a chart read as ECMWF's rather than as a generic rainbow, and it is why the pointer reports a band — "15 to 25 mm" — instead of a false precision the chart never claimed. The colour-table menu in the map options can repaint any field in a different table when you want one; the ecCharts palette is what you get back by choosing Default.
One raster covers South Asia, so India, IMD's four homogeneous regions and all 36 states and union territories in the picker are viewports on a field that is already drawn — which is why moving from Kerala to Ladakh is instant. That is affordable because each field is quantised to its own ecCharts band count rather than a flat 128 levels: a banded chart only ever claims which band a pixel is in, so the extra levels encoded noise nobody could read. The frame is wider than the country on purpose — west to the Somali coast, east to the Andaman Sea, south to the equator and north to the Tibetan Plateau — because the monsoon's moisture comes off the Arabian Sea and the Bay of Bengal, and a map cropped at the coastline cannot show a reader what is about to happen to them.
Steps are hourly to +90 hours, three-hourly to six days and six-hourly out to fifteen — the model's own cadence rather than an interpolation of it. Precipitation and snowfall accumulate over each step, so every frame states the interval it actually covers — 12 mm in one hour, in three and in six are very different forecasts, and the readout says which.
The upper air sits alongside the surface fields, at 0.25°: eight parameters — height, temperature, relative and specific humidity, wind, vorticity, divergence and omega — over the levels each is worth drawing on, 45 charts in all. They are banded for the tropics rather than for mid-latitudes, which matters more than it sounds: nine decametres is the whole spread of 500 hPa height over this frame in the monsoon, and a mid-latitude table stepping at 6 dam lands all of it inside two bands — a flat wash with the monsoon trough invisible in it. The tables here step at 2 dam through the range the subcontinent actually occupies.
Prefer a chart viewer to a free map? The legacy view bolts the camera down: a fixed set of framings, the whole run decoded up front, and loops that step instantly because nothing has to be re-fetched.
Data © ECMWF. Forecast India is not affiliated with ECMWF.