Lorraine Williamson
After another spell of unusually warm September weather, Wednesday will bring a very different picture to parts of the country. The most severe conditions are expected across eastern and north-eastern Spain and the Balearic Islands, where storms could bring hail and very strong wind gusts.
Spain’s state meteorological agency AEMET has warnings in place across seven autonomous communities for Wednesday 16 September, including orange warnings in some of the areas facing the heaviest rainfall.
Where will the worst weather hit?
Catalonia is among the areas expected to see some of the heaviest rain.
Orange warnings affect parts of Barcelona and Girona, where rainfall could reach 40mm in an hour and 100mm over 12 hours. In some areas of Barcelona, totals could exceed 100mm within just two or three hours.
In the Catalan Pyrenees, AEMET says rain during the second half of Wednesday could become locally strong and persistent around Girona and the Pre-Pyrenees. Hail is possible, along with very strong gusts around thunderstorms.
Valencia, Aragón and the Balearics also in the firing line
The unsettled weather will stretch considerably further south.
Parts of the Valencian Community face the risk of intense rainfall and thunderstorms, while Teruel in Aragón is under an orange warning for rain, with around 30mm possible in an hour. Moreover, storms there could also produce sizeable hail stones.
The Balearic Islands are another area to watch closely. Ibiza, Formentera and Mallorca are expected to experience strong or very strong thunderstorms as the weather system moves through, potentially accompanied by hail and powerful wind gusts.
A noticeable fall in temperatures
However, rain isn’t the only change.
AEMET is forecasting a marked drop in temperatures across parts of Spain as much cooler air moves in. The change could feel particularly pronounced after the very warm conditions experienced during the first half of September.
In Girona, for example, temperatures are expected to fall as Wednesday progresses, and cloud and thunderstorms develop. Meanwhile, mountainous areas of Catalonia are forecast to experience a notable temperature drop.
Not everywhere will experience severe weather, however. Large areas of Spain will escape the most intense storms, so it is advised to check the forecast for your own province rather than assuming the warnings apply nationwide.
Conditions can deteriorate quickly
The greatest concern with intense thunderstorms is how quickly local conditions can deteriorate.
Heavy rainfall concentrated into a short period can cause water to build rapidly on roads and in low-lying areas. Hail and sudden strong gusts can create additional problems for motorists, outdoor events and anyone travelling during the afternoon and evening.
Anyone living in or travelling through an affected area on Wednesday should check AEMET’s live warning map before setting out. Warning levels and affected areas can change as forecasters get closer to the event.
For much of Spain, September may still feel like summer. In parts of the country on Wednesday, however, it is going to look considerably more like autumn.