The State Meteorological Agency (Aemet) has issued a special warning for this Monday, when an “autumnal episode of widespread rain in the Peninsula and the Balearic Islands will begin, with the heaviest rainfall expected on the Mediterranean coast,” explains Rubén Del Campo, a spokesperson for the agency. In the eastern part of the Peninsula, the precipitation “may reach very intense and even torrential levels,” meaning more than 60 liters per square meter in just one hour, along with persistent rainfall and very strong winds. The first rains overnight have already caused road closures and flooding in much of the island of Mallorca, with no reported personal injuries. The temperatures during the storm, which may last until Saturday, will be typical for this time of year or slightly higher following a cold weekend.
The meteorological situation causing this episode is influenced by several factors. On one hand, there is a cut-off low (a “dana”), which brought rainfall over the weekend and will be situated from Monday over the Gulf of Cadiz, remaining almost stationary for much of the week. “This location favors atmospheric instability over the Peninsula and the Balearic Islands, and there will also be a low pressure system forming in the southern part of the Peninsula, which will bring easterly winds to the Mediterranean coast,” explains Del Campo. These winds will travel long distances over a Mediterranean Sea that is warmer than usual for this time of year, resulting in very moist winds reaching the Spanish Mediterranean coast.
“The interaction of the cut-off low with these moist winds will lead to the formation of storms with very heavy, persistent, and even torrential downpours in the Mediterranean area,” concludes the expert, admitting that “in these situations, it is difficult to estimate where the heaviest rainfall will occur.” The agency considers it possible that on Monday “the southern part of Catalonia and the northern part of the Valencian Community, as well as the Strait area, will experience the most precipitation.” In the afternoon, “the rainfall will also be intense in the eastern part of Andalusia, Murcia, and the southeast of Castilla-La Mancha,” adds the meteorologist. Six communities, as well as Ceuta and Melilla, are on alert on Monday, with an orange level warning in Andalusia, Catalonia, Valencian Community, Murcia, and Ceuta, and a yellow level warning in Aragon, Balearic Islands, Castilla-La Mancha, and Melilla.
Tuesday, which “could be the most adverse day of the episode,” will see significant impacts throughout the Mediterranean coast, from the southern province of Tarragona to practically the Strait of Gibraltar, where rainfall will be abundant, especially in the Valencian Community and the Region of Murcia, where precipitation could exceed 150 liters per square meter in some areas in less than 24 hours. This amount of rainfall in a short period of time is “an indication of the potential for significant river swelling and flooding in low-lying areas,” warns Del Campo. Intense showers can also be expected in the central and southern parts of the Peninsula on Tuesday, although not at the same level as those anticipated in the Mediterranean area. There will be alert warnings issued in seven communities, along with Ceuta, with Andalusia, Castilla-La Mancha, Murcia, Valencian Community, and Ceuta on orange alert, while Aragon, Balearic Islands, and Catalonia are on yellow alert.
From Wednesday onwards, “the forecast uncertainty significantly increases, as is common with these types of situations.” Currently, “the northern part of the Valencian Community and southern Catalonia, as well as southern Andalusia, are the areas most likely to experience very heavy rainfall.” On this day, there are yellow alerts in Aragon, Catalonia, and the Valencian Community. It is possible that on Thursday, the rain may “move towards the southwestern part of the Peninsula and the Balearic Islands, with the possibility of the peninsular Mediterranean being somewhat less affected, but this will need to be confirmed,” concludes Del Campo. Aemet estimates that the situation will last until Saturday. In addition to the rainfall, strong easterly winds will be a concern, leading to rough sea conditions in the Mediterranean area. Temperatures will generally remain normal for this time of year or slightly higher, with snowfall expected in higher altitudes, particularly in the Sierra Nevada region. The Canary Islands will be less impacted by the weather situation, although weak rainfall is expected in the northern part of the archipelago.
