Wintry signals in the weather models

Since late October, some model runs have shown the possibility of cold air moving into central Europe in mid-November, particularly between 13 and 18 November 2026.

Along with lower temperatures, some scenarios suggest wintry precipitation even at lower elevations. A single run is not a reliable forecast: at lead times longer than a week, large-scale weather patterns can change considerably.

GFS and ECMWF: what do the forecasts mean?

The US Global Forecast System (GFS) and the European ECMWF forecasting system are two important global weather models. Both can simulate winter-like weather but often disagree on timing, intensity and geographical extent.

What matters is not one dramatic run but whether the signal for colder weather persists across successive calculations.

Three possible mid-month scenarios

Scenario 1 – A pronounced cold snap: Cold air arrives from the north or northeast, temperatures fall and overnight frost becomes more widespread. Snow could reach lowlands if sufficient precipitation develops.

Scenario 2 – Cooler, but not a major winter outbreak: Upland areas may see snow while lower ground mostly gets rain or sleet.

Scenario 3 – Mild autumn conditions persist: Atlantic air wins out and the cold surge weakens or shifts east. There is no sound basis for assigning reliable probabilities to these scenarios at present.

What does this mean for North Rhine-Westphalia and the Rhineland?

For Bonn, Cologne and Troisdorf, a noticeable drop in temperatures would likely be the first sign. Snow in lowlands requires cold air, precipitation and a favourable temperature profile throughout the atmosphere.

Night frost alone does not guarantee daytime snowfall or snow cover. The Eifel and Sauerland uplands have better prospects for early winter conditions.

Why is the forecast still uncertain?

The position of high- and low-pressure systems over the Atlantic and Europe determines whether cold polar air or milder maritime air reaches Germany. Even a small shift can change the outcome.

Ensemble forecasts compare many slightly different model calculations. Greater agreement increases confidence in the predicted trend.

Conclusion: winter remains a possibility, not a forecast

A cold snap between 13 and 18 November 2026 is meteorologically possible, but a definite winter outbreak or widespread snowfall cannot be claimed.

The key question is whether the cold signal grows more consistent or the milder solution prevails.