The warning in the 17 districts will be in effect between 9 am on 27 May and 6 pm on 28 May, given the forecast of persistently high maximum temperatures.

The IPMA also placed the districts of Bragança, Viseu, Guarda, and Vila Real under a yellow warning between 12 pm and 9 pm on 27 May due to the likelihood of localised showers, sometimes with hail, accompanied by thunderstorms and strong gusts.

The yellow warning, the least severe on a scale of three, is issued whenever there is a risk to certain weather-dependent activities.

IPMA forecasts continued hot weather and showers in the interior North and Central regions on 27 May, accompanied by thunderstorms, which may occasionally include hail and strong gusts.

The forecast also indicates generally light winds predominantly from the east, suspended dust, especially in the North and Central regions, and a slight rise in temperature, particularly the minimum temperature.