Ibiza and Formentera are facing another day of intense heat before a significant change in the weather arrives later this week, with the State Meteorological Agency (AEMET) warning of high temperatures followed by stronger winds, rough seas and possible storms.

On Monday, September 7, both islands were under a yellow-level weather warning for high temperatures, with maximum temperatures expected to reach around 36°C in Ibiza and Formentera.

The warning was in force from 12:00 to 19:00, covering the hottest part of the day.

Another Hot Day Across the Pitiusas

The latest heat episode continues a run of unusually warm weather across the Balearic Islands.

AEMET forecasts indicated maximum temperatures of around 36°C for Ibiza and Formentera on Monday, while parts of Mallorca were expected to reach 37°C.

The yellow warning represents a low level of meteorological danger, but authorities still recommend taking precautions during the hottest hours.

For residents and visitors, that means limiting prolonged exposure to direct sunlight, staying hydrated and taking particular care during outdoor activities.

Weather Set to Change on Wednesday

The heat is not expected to last throughout the week.

AEMET is forecasting a marked change in conditions from Wednesday, September 9, when temperatures are expected to fall and wind conditions become more unsettled.

For Ibiza and Formentera, a yellow warning has already been established for coastal conditions during much of Wednesday.

Winds from the north and northeast could reach around 60 km/h, creating significantly rougher conditions at sea.

Possible Storms on Wednesday and Thursday

The change will not be limited to wind and temperatures.

AEMET is also forecasting the possibility of storms across parts of the Balearic Islands on Wednesday and Thursday.

The arrival of more unstable air will replace the settled, hot conditions that have dominated the start of September.

For Ibiza and Formentera, this could mean a noticeable contrast between the first part of the week, characterised by high temperatures, and the more unsettled conditions expected later.

A Sharp Contrast After the Heat

The weather change comes after a period in which temperatures have remained unusually high for the beginning of September.

The transition is expected to be relatively abrupt, with cooler daytime temperatures arriving alongside stronger northerly and northeasterly winds.

The shift is particularly important for people planning outdoor activities, boat trips and beach days later in the week.

Sea conditions could become considerably less favourable once the stronger winds arrive.

The Mediterranean Remains Exceptionally Warm

The incoming change is also taking place against the backdrop of an exceptionally warm Mediterranean.

Earlier AEMET data showed that the Mediterranean reached a record basin-wide surface temperature of 28.54°C on August 13, the highest value in its comparable records dating back to at least 1940.

That unusually warm sea is an important part of the wider meteorological context as the Balearic Islands move into the more changeable period of September.

A warm sea does not automatically mean severe storms will occur, but high sea temperatures can contribute additional heat and moisture to the atmosphere when the appropriate weather systems develop.

What Ibiza and Formentera Can Expect

For Monday, the priority remains the heat.

The yellow alert runs through the afternoon, with temperatures around 36°C expected.

Tuesday should provide a brief transition before the more substantial change arrives on Wednesday.

By Wednesday, temperatures should fall while northerly and northeasterly winds strengthen. Coastal conditions are expected to become more difficult, and storms are possible.

The unsettled weather could continue into Thursday, although the exact location and intensity of any showers or storms will depend on how the weather system develops.

A Reminder for Beach and Boating Plans

The weather shift is particularly relevant for Ibiza and Formentera because of the importance of the sea to daily life and tourism.

Boaters, swimmers and other water users should pay close attention to updated forecasts as the stronger winds approach.

Conditions can change quickly around the Pitiusas, particularly when northerly winds become established.

People planning excursions later in the week should therefore avoid relying solely on the calm conditions experienced earlier in the week and check the latest official forecasts before heading out.

Summer Heat Gives Way to Early Autumn Weather

The forecast marks a familiar turning point in Ibiza's calendar.

September can still bring hot, beach-friendly weather, but it is also the month when Atlantic and Mediterranean weather systems increasingly begin to influence the islands.

The expected drop in temperatures and increase in wind and storm activity are therefore a reminder that summer conditions are no longer guaranteed every day, even while Ibiza remains firmly within its tourism season.

For now, however, the island still has to get through another very warm afternoon.

Key Facts

• Date of heat alert: Monday, September 7, 2026

• Islands affected: Ibiza and Formentera

• Alert level: Yellow

• Phenomenon: High temperatures

• Expected maximum: Around 36°C

• Heat warning hours: 12:00 to 19:00

• Expected change: Wednesday, September 9

• Wednesday coastal warning: Yellow

• Wind direction: North and northeast

• Possible wind speeds: Around 60 km/h

• Storms: Possible Wednesday and Thursday

• Main weather trend: Heat followed by cooler, windier and more unsettled conditions