Twelve mainland districts are under yellow alert this Tuesday, March 10, due to forecasts of rough seas and snowfall, according to the Portuguese Institute for Sea and Atmosphere (IPMA). The districts of Guarda and Castelo Branco were under yellow alert until 03:00 due to snowfall above 1,400 metres. In a statement, the IPMA warns that snowfall, accumulation, and potential ice formation may cause disruption, such as restricted or closed roads, damage to structures or trees, and hindered local supplies. Until 06:00, the districts of Aveiro, Porto, and Braga were under yellow alert due to rough seas. The same alert for rough seas applies to the districts of Coimbra (until 09:00), Leiria (until 12:00), Lisbon (until 13:00), and Faro, Beja, and Setúbal (until 15:00). The institute forecasts north-westerly waves between four and 4.5 metres high. A yellow alert is issued by the IPMA whenever there is a risk situation for activities dependent on weather conditions. For today, the IPMA forecasts showers on the mainland, especially in the Centre and South, which will be snow in the highlands, as well as ice formation and a drop in minimum temperatures and a rise in maximums. Minimum temperatures will range between 1 degree Celsius (in Guarda) and 10 (in Faro), and maximums between 9 (in Guarda) and 17 (in Braga). Snowfall places ten districts under yellow alert.