Heavy rain in eastern Spain: over 150 litres in under six hours

Madrid, 30 September 2026 – On Wednesday afternoon the Spanish weather service AEMET issued a special information notice about an approaching spell of severe weather. It mainly affects the eastern third of the Iberian Peninsula. According to AEMET the situation begins on Thursday, 1 October, and is likely to last at least until Monday, 5 October. The probability of the situation described is given as 70 percent.

The focus is initially on the Mediterranean coast

The trigger is a front that crosses Spain from west to east on Thursday, linked to a deep low over the North Atlantic. Behind it, colder air flows in at higher levels. At the same time, very humid air from the Mediterranean reaches eastern and northeastern Spain.

From Thursday midday the rain is expected to set in over the eastern interior first and then spread towards the Mediterranean coast.

The main focus is on Castellón, Valencia, the northern coast of Alicante province and southern Tarragona. Neighbouring areas of the provinces of Lleida, Teruel and Cuenca may be affected as well. Showers there can be locally very heavy.

More than 150 mm in under six hours possible

It is not only the intensity that deserves attention, but also how long the rain may last.

According to AEMET, the rain can be persistent especially from late Thursday into the first half of Friday. That applies above all to coastal areas and the hinterland of the Mediterranean coast.

Locally, rainfall totals of more than 150 millimetres within less than six hours are possible. 150 millimetres correspond to 150 litres of water per square metre.

AEMET therefore explicitly warns of the danger of sudden local flooding. Low-lying areas are particularly at risk, as are streams and the ramblas typical of the Spanish Mediterranean, which can turn into raging watercourses within a short time during heavy rain. The weather service rates the potential danger level of this situation as high.

The Balearic Islands could be affected too

As the situation develops, the Balearic Islands also come into focus. Strong thunderstorms and locally heavy to very heavy showers are possible there, especially from the late hours of Friday.

Over the weekend, rain is expected across larger parts of the Iberian Peninsula. The highest amounts are still expected in the east, although AEMET currently expects lower intensities and totals than during the particularly critical phase on Thursday and Friday.

A DANA could extend the situation until Monday

What happens next is meteorologically interesting as well: from Sunday, AEMET expects an upper-level low, a so-called DANA, to possibly cut off to the west of the Iberian Peninsula.

As a result, the atmosphere over Spain and the Balearic Islands is likely to remain unstable. At the same time, however, forecast uncertainty increases considerably. Even small changes in the position and development of the systems involved can determine where the largest amounts of rain ultimately fall.

For that reason, one should not rely solely on individual rainfall totals or model calculations for the weekend at this stage.

Radar and NowCast: follow the situation closely

For residents and holidaymakers, especially in Valencia, Castellón, the north of Alicante province, southern Tarragona and later possibly on the Balearic Islands, the message is therefore: follow developments closely over the coming days.

In convective heavy-rain situations in particular, large differences can occur over comparatively short distances. Where strong thunderstorms move repeatedly over the same areas, rainfall totals can rise considerably within a few hours.AEMET announced that it would update its special information notice on Thursday. Because of the remaining uncertainties, the Spanish weather service also explicitly recommends following the latest forecasts and official warnings regularly.

As of 30 September 2026, 14:21. Source of the official special information: AEMET, edition of 30 September 2026, 13:46.