Likely related to latent heat release of late season tropical cyclones in both the North Atlantic and Northwest Pacific, a gathering of anomalous warm air aloft leading to a high-pressure block convenes over Greenland characteristic of a strong negative phase North Atlantic oscillation. In the middle latitudes, compensating cold trough patterns develop and replace the prevailing very warm climate of autumn 2024.

In Europe, an upper trough brings snow to Northern Europe to reverse the lack of early season snow in that region this weekend (Fig. 2). By Monday, a wintery feel with wind is emerging across U.K., North-central Europe, and Northeast Eurasia. A mid-next week rainstorm emerges over West-central Europe with trailing cold air that could cause some snow in U.K. and possibly as far south as Northern Spain.

The past 30 days are scorching hot across Australia, the hottest since 2015. However, "weeklies" forecasts from ECMWF generate rain-producing upper troughs the second half of November helping to dissipate the widespread hot regime.