The first weekend of October will be marked by the arrival and passage of a cold front associated with an Atlantic storm, which will travel much of the peninsula from northwest to southeast and collapse the thermometers on Sunday, with 6 to 13 degrees less in the north, so that long-sleeved clothing or coat will be necessary and even the first autumn snows will arrive to the Pyrenees and the Cantabrian Mountains.
The cold front will begin on Saturday at noon on the coast of Galicia and will sweep the peninsula to reach the Mediterranean on Sunday, which will rid Andalusia, Murcia and Alicante. In its wake it will leave rainfall in the extreme north of the peninsula, which on Sunday will reach the Balearic Islands, according to the State Meteorological Agency (Aemet).
The rains will be especially abundant in the Bay of Biscay and may be locally strong and accompanied by a storm the end of Saturday in the Pyrenees and during Sunday in the north-east of Catalonia and the north of the Balearic Islands, as well as persistent in the eastern Cantabrian. In the rest of Spain, stable weather will predominate, with clear skies, not very cloudy or with cloud intervals.
With the passage of the front there will be an almost generalized thermal descent, which will begin on Saturday in the northwest and will affect almost the entire peninsula and the Balearic Islands on Sunday. The fall in the thermometers will be noticeable in the center and inland of the north of the peninsula, with which temperatures are expected lower than normal in the northern half, especially the Cantabrian, the upper Ebro and the western Pyrenees.
The prediction of the Aemet, collected by Servimedia, indicates that the fall of the temperatures will be remarkable or extraordinary this Sunday in many zones of the north, with 13 degrees less in Vitoria; 12 in Burgos, Logroño and Soria; 10 in Palencia and Valladolid; 9 in Salamanca and Teruel; 8 in Ávila, León, Pamplona, Segovia and Zaragoza; 7 in Guadalajara, and 6 in Bilbao, Huesca, Madrid and Toledo.
Also, on Sunday will fall the first snowflakes of autumn, since the height will fall to between 1,600 and 1,800 meters in the Pyrenees and the Cantabrian Mountains.
The cold front will not affect the southern third of the peninsula, where temperatures will exceed 30 degrees, especially in Cordoba (34 degrees on Saturday and 32 on Sunday) and Seville (33 and 31), while the autumnal environment will take over all the half north with thermometers less than 18 degrees, except in the Ebro valley, the Catalan coast and the depressions of the northeast.
Among provincial capitals, the lowest maximum temperatures this Sunday will be in Burgos and León (14ºC); Oviedo, Soria and Vitoria (15); Palencia and Pamplona (16); Ávila, Bilbao, Lugo, San Sebastián, Santander and Valladolid (17), and Logroño and Segovia (18).
On the other hand, next week will begin with still unstable environment in the Balearic Islands and Catalonia due to the presence of a cold drop in height, which is expected precipitations that could be strong locally and accompanied by a storm. The rains can occur on Monday also in the eastern Cantabrian and southeastern Peninsula, and on Tuesday throughout the Mediterranean area.
At the end of Wednesday or Thursday, it is likely that there will be a front off the coast of Galicia, although there is still a considerable uncertainty about its intensity and subsequent geographical reach, according to the Aemet.
Associated to the passage and activity of this front would be precipitations in the peninsular northwest, that could affect of weaker and dispersed form to the rest of the Atlantic slope, and would be more abundant in the west of Galicia.
As of Friday, the meteorological uncertainty is high and it is difficult to determine the distribution and intensity of rainfall that could occur, although the rains would be more likely and abundant in the northwest third of the peninsula, especially in Galicia.
As for the Canary Islands, next week the probability of precipitation in the mountainous islands, which would occasionally be strong in a timely manner, is maintained.
Temperatures next week will start with values below those usual in many areas, and will tend to increase from Tuesday, especially in the Bay of Biscay, the east of the peninsula and the Balearic Islands.