Translation:With this sunny spell, you can go walk your dog.
In English english you would not say go walk your dog. You would go and walk your dog. Or walk your dog. But not go walk
I used the word bank for this and picked "sunny spell" as the only words there that would make sense of the sentence. However, I was confused by the word and its closeness to lightning and looked on line for a translation, but found nothing. My (40 year old) dictionary had the best suggestion with "break, opening, rift (in the clouds)". So is "break in the clouds" acceptable? Sunny spell seems something that would last a lot longer than just a break in the clouds. Edit - I can now add that "break in the clouds" is not accepted, but "break in the weather" was given as an alternative.
Right you are. It is a good dictionary definition, but not very natural in common speech. I've added a (correct) more natural phrase, "break in the weather".
I've also never heard that phrase. The question also does not seem to accept 'with this sun' or 'with this sunny day' which are more what I'd say in English.
Because "éclaircie" does not mean "sun", nor does it mean "sunny day". If refers to an interval of sunny weather which may be between clouds or rain.
You can walk your dog, but to say you can go walk your dog is simply not English
I agree with you that "go walk" is NOT English. It is wrong in grammar.
However, it seems that there are quite some people saying that way. I think it comes from the oral speaking with "to" omitted in between the two verbs, and some people just do not realize it.