The IPMA placed at high risk more than 40 municipalities in the districts of Bragança, Vila Real, Viana do Castelo, Braga, Viseu, Guarda, Castelo Branco, Portalegre, Santarém, Beja and Faro.
The remaining territory faces a high, moderate, and low risk, depending upon the region.
The fire risk determined by IPMA has five levels, ranging from reduced to maximum.
Calculations are obtained from air temperature, relative humidity, wind speed and amount of precipitation in the last 24 hours.
The critical fire period lasts until the end of September and until then it is prohibited to make extensive fires or burning piles without authorization, to use stoves or grills throughout the countryside, and to smoke or make any kind of fire in the forest areas.
It is also prohibited to launch balloons from burning fuse or rockets or to carry out work in the forest that could cause sparks.
For today, IPMA predicts the possibility of rain or showers until mid-afternoon and more intense wind in the highlands.
A small increase in the minimum temperature in mainland Portugal and a small increase in the maximum in the North region are also expected.
The minimum temperatures will vary between 12º (Bragança) and 18º (Lisbon and Faro) and the maximum between 22º (Aveiro and Porto) and 30º (Castelo Branco)