The day of the Chupinazo (the firing of a rocket) will be the freshest and during the Procession, on the 7th, there is probability of some weak storm.
The State Agency of Meteorology (AEMET) announces risk of rains for most of the Fiesta. On Sunday the 6th, they predict a cloudy or very cloudy day, with weak rain or isolated storms and a maximum temperature of approximately 23ºC.
The clouds and the rain will continue the 7th, but the weather will be improving reaching on Saturday the maximum temperatures, which can court the 31ºC. Nevertheless, some weak storm does not discard in the early morning which can concern the running of the bulls.
On Sunday the 13th, the temperatures will suffer a decrease with maxims of 25ºC and also with probability of rain in the early morning. Weak wind but from North will do that the temperature of the last day of the Sanfermines does not rise of the 24ºC.