Are "fire" and "wind" countable noun.

As I was reading a book and found a sentence stating

1."Early man may have been found the roasted meat in forest fires tasty."

2.In similar way "the strong winds.......".

Yes, they are countable when you regard them as single 'items'.

Fire in your example refers to small fire-places early man have set up to be able to roast meat - that can mean that at the same time, some other people have also set up a fire, then you have two fires already.

Wind is countable as well when you want to express that there are different kinds of wind, e.g. a trade wind, an eddy wind, a slope wind, a south wind, a north wind, a surface wind etc. all these are different "winds".
Is wind uncountable in this sentence? Should I omit the 'a'?
October 31. I left the Canary Islands today...There's a strong wind and plenty of sunshine now.