Catalonia is preparing for a week of unstable weather, with forecasts predicting a "rollercoaster" of showers and temperature drops across the region starting on Tuesday, according to meteorologists.
The shift follows a weekend that saw generous rainfall across the Catalan coast and pre-coastal areas on Saturday, with some locations receiving over 20 litres per square metre. This moisture led to morning fog banks in the Pre-Pyrenees and Girona on Sunday, creating a cool start before clear skies and moderate winds brought warmer temperatures, exceeding 26 °C in inland Girona. However, western areas experienced afternoon showers and thunderstorms from Aragon.
Monday's Forecast: Stable Start Before Change
Monday is expected to begin with stable conditions across much of Catalonia, featuring sunshine, mild temperatures, and some afternoon showers. The morning will see clear or partly cloudy skies, with temporary low clouds along parts of the coast and pre-coastal areas, particularly in the north, which will quickly dissipate. Similar low clouds and potential fog are also expected in the central depression and parts of the Pre-Pyrenees, leading to cooler, more humid conditions in inland valleys.
By midday, large clouds will develop across the Pyrenees and Pre-Pyrenees, as well as in the north-eastern interior. Isolated showers are possible in the Catalan pre-coastal mountains. Rainfall is forecast for the northern third of Catalonia in the early afternoon, with weak to moderate showers primarily affecting the eastern Pyrenees. The Ripollès and Garrotxa areas could see more intense downpours, possibly accompanied by thunderstorms. These rains might extend, albeit weaker, to inland Girona, northern Barcelona, and Alt Empordà by late afternoon. Other parts of the region will experience more stable, clearer weather with sun and thin high clouds.
Moderate south-westerly winds are expected along the central coast, with gusts potentially exceeding 40-45 km/h. Elsewhere along the coast, lighter southerly winds will prevail. In the afternoon, strong westerly winds are predicted for parts of the central plateau and western Pre-Pyrenees, with gusts over 40 km/h. Temperatures will remain largely unchanged, though maximums could rise slightly along the central coast and pre-coastal areas, reaching 24-25 °C. Western Catalonia, the Ebro Valley, and the Tarragona coast will see mild to slightly warm conditions, with highs around 25 °C. In contrast, temperatures in the north-east could drop below 22 °C due to cloud cover and rain. Nights will be mild along the coast and cooler inland.
Mid-Week Instability and Polar Air Arrival
Tuesday will bring significant weather contrasts to Catalonia. The morning is set to be sunny and clear across the region. However, by mid-morning, clouds will start to form due to a small pocket of cold air at high altitudes, destabilising the atmosphere. These clouds will develop across the Pyrenees, Pre-Pyrenees, inland areas, the pre-coastal strip, and the north-east, making skies cloudy or even overcast across much of the country in the afternoon. Rain is expected in these regions, with weak to moderate showers that could become more intense and include thunderstorms. Hail is also possible in some inland areas. Precipitation will spread throughout the afternoon, potentially affecting almost any part of Catalonia. By night, clear spells will emerge, starting in the south-west, with rain becoming limited to the northern Pyrenees and the coasts of Barcelona and Girona.
From Wednesday, changes will become more apparent with the arrival of a polar air mass from northern Europe. A low-pressure system near the British Isles and another smaller one near Italy will combine with the Atlantic anticyclone to bring cold air, both aloft and at the surface, to Catalonia. The first sign will be strong north-westerly winds at both ends of the region. The convergence of surface winds off the central and northern coasts will lead to increased cloudiness in eastern Catalonia, potentially bringing morning rains and a slight cooling to the Barcelona and Girona areas. In the afternoon, the usual Pyrenean afternoon showers will add to this, possibly keeping rain active in the north-east for hours, with local thunderstorms. Western and southern Catalonia will experience more stable weather with sun and milder temperatures.
Cold Front and Significant Temperature Drop
Thursday will see the cold disturbance fully manifest with a general increase in cloudiness. Cooler conditions and less sunshine are expected from the morning, consolidating with the passage of an active cold front that will sweep across Catalonia, bringing widespread rain. The rains are expected to be abundant and persistent, potentially affecting many areas throughout the afternoon. The heaviest precipitation is forecast for inland areas, the Pyrenees, the north-east, and parts of the far south, with potential thunderstorms, lightning, and thunder.
Instability will continue into Friday, with potential rainfall in eastern Catalonia during the early morning. The atmosphere may not clear completely in the afternoon, as persistent precipitation could still affect eastern areas. A notable drop in temperatures is expected across Catalonia, with the north-east experiencing cold conditions more typical of March, with maximums below 16 °C. The snow line will fall, potentially bringing snow below 1,500 metres. The weekend, however, is expected to bring a return to spring-like weather, with more sunshine and rising temperatures.
