About IFS ENS
ECMWF · Ensemble · IFS with perturbed initial conditions and stochastic physics, 51 members
The ECMWF ensemble runs the physical model many times from slightly different starting points. Its mean is a forecast; its spread says how much to trust it. The spread and percentile fields here are the reference band every single-run model on the Board is read against.
Where a learned model's forecast leaves the ensemble's 10–90% range, it is making a claim the physics ensemble does not support. That is worth knowing before believing it.
Why it is on this site. A learned model that leaves the ensemble's 10–90% band is making a claim the physics ensemble does not support. That is the most useful single sentence this site can print about a run.
Maps rendered by Forecast Euro and read here unchanged. Data © ECMWF, CC-BY-4.0. Not affiliated with ECMWF. Full model facts →