How might weather conditions affect the outcome of a battle?

I believe the answer is:

- by making air power difficult to use, by preventing troop movements, impacting weaponry due to rain or snow, or any number of ways.

For example, in launching a missile projectile, the wind current could make the missile deviate from its original destination.

The waves and water current also could prevent the navy to reach its destination on time and might cause them to lose the War.

Weather patterns can often favor one side or the other or impact both sides in similar ways. 

fir trees are found in areas with cooler climates. fir trees have needles for leaves and remain green year-round.

productive most commonly means: achieving or producing a significant amount or result.

explanation:

productive can also mean:

these depend on how the word productive is used. most likely productive will mean   achieving or producing a significant amount or result.