A radical change in the weather is coming: from the warm summer to the cold of midwinter.

BarcelonaThe weather will undergo a radical change in the coming days. The arrival of a mass of very cold air of Arctic origin will cause temperatures to plummet throughout the week. Each day the mercury will drop further, and by midweek, thermometers will register between 5 and 10 degrees lower than usual for this time of year. This cold, wintry weather has arrived earlier than usual this year, with more than a month still to go before winter officially begins. Aemet (the Spanish State Meteorological Agency) has already issued an advisory warning of this cold spell.

Therefore, we'll have to get our coats out of the closet as quickly as possible, after the unseasonably warm weather we've had in recent days. We'll go from one extreme to the other. On Thursday, a front will arrive bringing snow to the Pyrenees and showers to other regions. And watch out for the snow level, as it will also plummet. Much of Europe will be under the effects of this Arctic outbreak, with harsh winter conditions and snowfall at low elevations.

Temperatures in freefall

The mass of very cold air will be approaching Catalonia in the coming days. This Tuesday, the mercury will drop significantly, both day and night. We will wake up to quite cold temperatures, and frost will become more widespread in the Pyrenees and Pre-Pyrenees. Maximum temperatures will also be lower, with many reaching 12 to 17°C, and even lower in mountainous areas. Temperatures will drop even further on Wednesday, and will reach their lowest point on Thursday and Friday, with midwinter cold and many highs only between 5 and 10°C, significantly lower in mountainous areas. Nighttime frosts will become more prevalent in these areas, and temperatures could reach -15°C at higher elevations in the Pyrenees.

To give you an idea of the change we'll experience, the temperature at 5,500 meters altitude will drop below -34°C in the early hours of Friday, compared to around -12°C before last weekend. At 1,500 meters altitude, average temperatures will be -3 or -4°C, whereas just days ago the thermometers were approaching 10°C. These two reference values demonstrate the sharp drop in temperature that the mercury will experience. In just a few days, we'll go from above-average temperatures to values clearly below the usual November levels, as shown in this graph:

Saturday will remain very cold, especially early in the morning, but the high will recover slightly. It will be from Sunday onwards that the Arctic air mass will begin to move away for good, and temperatures will gradually return to normal.

Snow at fairly low elevations

The influx of cold air will be quite dry across much of Catalonia, but some precipitation is also expected, with a sharp drop in the snow level. The first showers will arrive in the Vall d'Aran and northern Pallars Sobirà starting Wednesday afternoon or evening, with the snow level falling from 1,300 to 1,000 meters. On Thursday, a front will cross the region, bringing snowfall to the northern slopes of the Pyrenees, which may intermittently extend to the southern slopes. Scattered showers are also expected in the Girona and Barcelona regions. Be aware that the snow level will drop below 800 meters throughout the day, and by the afternoon or evening, it could even fall to 600 or 500 meters.

Therefore, snowfall is possible in areas such as Montseny, the Transversal mountain range, the Pre-Pyrenees, and other pre-coastal mountains. However, according to current weather maps, any snowfall outside the Pyrenees will be minimal. In contrast, snowfall could accumulate more than 20 or 25 centimeters in the higher elevations of the Alt Pirineu in the coming days. Showers and heavy thunderstorms are also expected in the Balearic Islands between Thursday and Friday, with the possibility of snow in the Serra de Tramuntana mountain range of Mallorca. Strong northerly winds will blow at the extremes of the region, and the weekend will be calmer and sunnier.