Would a summer sleeping bag be enough on the Camino Frances (and possibly camino Invierno) in September/October?

[verar]

I'm planning to be walking the camino Frances from the second half of September - end of October. I got super lightweight awesome sleeping bag for my birthday (the Sea to Summit Flame F0) which has a comfort rating of 13 degrees Celcius. I tried it last night in my bedroom at 15 degrees Celcius (I like to sleep in a chilly space) with few clothes on and I was borderline comfortable, found myself wrapping up to foetal position more than usual.

I'm planning to sleep in albergues, mix of private and municipal. Will they be heated? Blankets should often be available, but will the sleeping bag be enough in the occasional unheated albergue?

I might deviate to the camino Invierno from Ponferrada, I understand there might be more unheated albergues there. Would this be unrealistic with just a summer sleeping bag?

Just trying to get a feel here. I can still return it and opt for a slightly heavier/warmer model.

 

[dreaming]

Hi. I walked CF last October. The first two weeks were hot above 30 degrees Celsius and the third and fourth week it was cold and wet. I took a 600 gm Decathlon sleeping bag 60 Australian dollars and it was fine10-20 degrees Celsius . A lot of the private albergues had blankets and the occasional duvet. I took a sleeping sheet as well. The donativos didn't have blankets . I wore a fleece vest, merino wool long sleeved top and leggings to bed.
Your sleeping bag will be perfect.