The first day of 2026 will be marked by heavy rain, strong winds and rough seas across mainland Portugal, due to the arrival of Depression Francis, with the most severe conditions expected in Madeira, according to the Portuguese Institute of the Sea and Atmosphere (IPMA).
Meteorologist Maria João Frada told Lusa that forecasts have changed significantly in recent days. “There have been major changes compared to earlier forecasts, which did not indicate precipitation. Over the past two days, the situation has shifted considerably, and the passage of the Francis depression will now bring rain,” she said.
Until Wednesday, weather conditions will continue to be influenced by an anticyclone located south of Iceland, extending towards western Europe and carrying a mass of polar air over mainland Portugal.
“Today (December 30) will bring partly cloudy skies, cold temperatures and morning mist or fog, particularly inland and in river valleys,” Frada said. Fog may persist throughout the day in the north-east of Trás-os-Montes and Beira Alta, where conditions are also favourable for frost formation.
In these inland areas, the combination of fog and sub-zero temperatures may lead to the formation of rime ice.
From Wednesday onwards, the weakening of the anticyclone ridge will allow Depression Francis to move closer, bringing frontal systems that will cause rainfall on New Year’s Day, along with strong winds, particularly along the coast and in highland areas.
According to the meteorologist, light rain is expected in the Algarve from Wednesday afternoon (New Year’s Eve)*, continuing into Thursday. “In the early hours of Thursday, there may also be light rain south of Cabo Raso and Cabo da Roca,” Frada said.
On Friday, precipitation is forecast across mainland Portugal, at times heavy, accompanied by strong winds.
Minimum temperatures will rise slightly on Wednesday but will still range between 0°C and -3°C in many inland areas of the north and centre.
Rough seas are expected on Thursday, with waves reaching between 2 and 3.5 metres.
Severe weather expected in Madeira
In Madeira, conditions are expected to deteriorate from Wednesday afternoon, with heavy rain forecast, particularly on the southern slopes, in highland areas and in the western part of the island.
IPMA has issued an orange weather warning for the southern slopes and highlands. “If the current scenario persists between midnight and 6am on Thursday, warning levels, particularly in the highlands, may be raised to red,” Frada said.
Thunderstorms, hail, strong winds with gusts of up to 85 km/h — rising to 115 km/h in the highlands — and rough seas with waves of 3 to 4 metres are also forecast for Madeira.
Azores also affected
In the Azores, the approach of a frontal system is expected to affect all islands from Tuesday onwards, bringing periods of heavy rain.
On Wednesday and Thursday, unstable conditions linked to the circulation of the Francis depression are expected to cause showers across the archipelago, particularly in the central and eastern groups, along with strong winds and waves of between 2 and 4 metres from the east.
Source: IPMA/Lusa
*According to Meteofontes weather forecast for New Year’s Eve, skies will be partly to very cloudy across the country, with the chance of light drizzle in the south during the morning and early afternoon, although no significant rainfall is expected. Morning mist or fog is likely in inland northern and central areas, along with the formation of frost. New Year’s Eve is expected to remain dry. Temperatures will be around 9°C in the Algarve, 5°C in the Alentejo, 4°C along the northern coast and -1°C in the northern interior. Winds will be light to moderate from the east.
