What about Having Random turns where the Weather (might) turns sour. Making it trench warfare.
Specifics/Details:
Every once in a while a random Weather would a cure and that specific turn would be trench warfare.
For one full round (or two). might be every 3rd turn the weather have a chance to turn sour.
Of course it would be stated to all players that a specific turn has a chance to go Trench (Bad Weather)
How this will benefit the site and/or other comments:
It would be a whole new game.