Weather

is there any way of having the weather being random and affecting the gameplay?

Does weather affecting gameplay seem like it should be in site discussion?
Wrong forum again, mate.

As for your question, I beleive so, i think I've seen it before, but I'm not sure how.

the only way i could think of doing this would be with triggers (if there are any triggers that effect weather)

The closest thing to what you're talking about I have seen used was in a map called Dragon's Wail, where the weather changed according to the player's location on the map and sometimes just randomly. Good for atmosphere, and you can do it quite easily with the Environment triggers and a decent regions set-up.

As for it affecting gameplay, again, you could use triggers to have unit's movement speed and vision range affected by it; I'm not sure how though. There is a movement speed change trigger somewhere, but for the rest, it might be easier to make custom buffs for each type of weather and then have them applied to every unit on the map when you change the weather, while removing previous weather buffs. I haven't looked at the buff editor yet, though, so this is just a guess.

Hope that helps.

~--MOVED--~

set up a variable thing, where if it is set to 1, you run the trigger for 1, and if it is 2, run the trigger for 2...and so on...
the triggers will have weather being activated, and having the units being effected by triggers