weather on rtw...

[Kekvit Irae]

It depends on what region you are in. Carthage, Italy, Spain have dry weather for the most part. In anything north of the Pyrenees or the Alps, you will get rain/snow in every battle. It cycles about every 5 minutes...just like in MTW. The strange part about the rain is that it is hard to tell it is raining. The new engine doesn't do weather very well.

Personally, I believe that the effects for heavy rain should be the same as most MMORPGs (IE: EverQuest and Dark Age of Camelot), where a heavy "fog" obscures everything except for a radius small around you. That would be quite interesting to see if it could be implimented in the expansion...

[Titus Livius]

I was just in Numidia (in the game) and had to fight through a pretty cool sandstorm. It looked pretty much like the real thing, and had most of the same effects (ie, reduced visibility and making a gritting sound when you walk).