Formentera was among the areas hardest hit by Storm Adam on Sunday, 18 October 2026, as torrential rainfall flooded parts of the island and transformed Cala Saona beach into a torrent. La Mola recorded 178.4 litres of rain per square metre by 12:45, the highest reported accumulation in the Pitiusas at that point in the storm.

The intense downpour caused significant disruption across Formentera, with floodwater affecting roads, homes, businesses and public areas. Images from Cala Saona showed water rushing across the beach, carrying sediment and debris and dramatically altering the appearance of the coastline.

Ibiza and Formentera were placed under a red weather alert as the storm brought exceptionally heavy rainfall and a risk of further flooding.

La Mola Records the Highest Rainfall in the Pitiusas

The rainfall recorded at La Mola reached 178.4 litres per square metre by 12:45 on Sunday, according to the weather figures reported during the storm.

Other stations also recorded substantial accumulations. A second weather station in Formentera registered 120.4 litres per square metre, while Ibiza Airport recorded 119.5 litres over the reported period.

The figures illustrate the intensity of the rainfall, although accumulations varied considerably between locations.

Later measurements showed that the rain continued to accumulate. AEMET subsequently reported 195 litres per square metre over 24 hours at its Sant Francesc station in Formentera. This was a separate reading from a different station and covered a longer period than the 178.4 figure recorded at La Mola by 12:45.

Cala Saona Beach Transformed by Floodwater

Cala Saona was among the most visibly affected locations. Torrential runoff flowed across the beach, creating a broad channel through the sand and carrying material towards the sea.

The heavy rain overwhelmed the natural drainage of the surrounding area, turning parts of the beach into a torrent. Images from the scene showed the scale of the water flow and the sediment deposited across the sandy area.

The incident highlighted how quickly intense rainfall can alter coastal landscapes, particularly where runoff from inland areas reaches the shoreline.

The full extent of any lasting damage to the beach was not established in the reports reviewed.

Flooding Causes Widespread Disruption Across Formentera

The impact extended well beyond Cala Saona. Emergency services received numerous calls involving flooding in private homes, businesses and public spaces, as well as fallen trees and other weather-related incidents.

RadioIlla reported that the island experienced around 60 incidents during the first part of Sunday as the storm moved across Formentera. Firefighters and Civil Protection teams responded to several cases of flooding and other emergencies.

The speed and volume of the rainfall created particular difficulties in low-lying areas and near natural drainage channels, where water could accumulate rapidly.

Residents were urged to avoid unnecessary journeys, keep away from torrents and flooded roads, and follow instructions from emergency services.

Red Weather Alert Across Ibiza and Formentera

The severe weather prompted authorities to raise the alert level to red across the Pitiusas on Sunday, with forecasts warning of further intense rainfall.

AEMET had warned that rainfall accumulations could reach very high levels over a short period, creating a significant risk of flooding. Emergency services issued public warnings and reinforced their response as the situation developed.

The storm also affected Ibiza, where streets, roads and buildings experienced flooding and airport operations were disrupted.

Formentera's rainfall figures and the damage seen at Cala Saona demonstrated the severity of the episode, while officials continued to urge residents and visitors to take precautions as weather conditions evolved.