Should I refinish Spanish stucco in winter or wait until Spring?
Widen the cracks to an inverted "V" shape and fill with a good quality latex caulk (do this on the next mild dry day). Water wont penetrate a sound stucco wall but the cracks may allow it to seep through. If the forecast calls for warm weather, 60 degrees or better, for 2 consecutive days than it is alright to do some painting. Wrap up early afternoon before it gets cold.