Ilma is a weather forecast for any place on earth, seven days ahead, hour by hour. It averages six forecast models and shows the band the models fall in: a narrow band means a confident forecast, a wide one means the models disagree and you should plan for both outcomes.
The forecast's accuracy is verified every night against 14 Finnish weather stations, and the results are published on this page. The site claims to be better than a named competitor only when the difference is statistically significant.
Ilma is also built for AI agents. The page registers 19 WebMCP tools, so an agent in your browser can read calibrated probabilities, see how stable the forecast is, mark the chart you are looking at, and write a plan you both can edit.
Ilma averages six forecast models: ECMWF AIFS and its ensemble, ECMWF IFS, MET Nordic, the Finnish Meteorological Institute's edited forecast and Open-Meteo. The shaded band on the chart shows how much the models disagree.
Accuracy is verified every night against 14 Finnish weather stations, and the results are shown on the page. The site claims to beat a competitor only when the difference is statistically significant.
Ask about the weather in your own words, for example whether Saturday evening works for an outdoor event. The assistant uses the same tools that browser AI agents get: calibrated probabilities, forecast stability and when to decide.
WebMCP is an open standard that lets a web page offer tools to AI agents running in the browser. Ilma registers 19 tools, so an agent can read verified probabilities and mark the chart the human is looking at.