The Portuguese Institute of Sea and Atmosphere (IPMA) has also placed the islands of Porto Santo (Madeira) and Flores (Azores) at high risk of exposure to UV radiation.
For regions with very high risk, IPMA advises the use of sunglasses with UV filter, hat, ’t-shirt', umbrella, sunscreen and avoid exposure of children to the sun.
The calculation is made based on the values observed at 13:00 each day for air temperature, relative humidity, wind speed and amount of precipitation in the last 24 hours.