Gas storage forecast · methodologyHow the forecast is built and checked

In brief

Each of the seven markets (Germany, Austria, the Netherlands, France, Italy, Czechia and Poland) has its own ARIMAX model of the daily change in storage fill, driven by heating degree days from Open-Meteo, cross-border flows from ENTSO-G, gas-fired power from ENTSO-E and the TTF price. Fill levels come from GIE AGSI+. 2,000 simulated paths give the 14-day forecast, its P10–P90 range and the probability of falling below 15%. The range is calibrated per country with a scaling factor and checked two ways: a rolling-origin backtest and the public track record, which scores every published forecast against the reported outcome. The German winter outlook is separate: a daily gas balance of imports, production, exports and temperature-driven demand, replaying the weather of 36 past winters. Its cases are scenarios, not forecasts.