Weather
Zones might be randomly met with weather effects. They usually last a few minutes, in rare cases up to an hour. Those weather effects will almost always have gameplay effects. Some might block your vision. Others slow you down.
Sandstorm
Arguably the worst weather effect when you try to run away, and the best if you try to catch someone. A sandstorm will force you to walk while outside. So in order to diminish the effects of it, try to find a building. Hugging walls on the outside also sometimes works - but not always. It is important to note that NPCs might be immune to this effect, though this might have been patched out.[Unconfirmed]
Cloudy
This weather effect will severely hinder your sight range, as random spots of little smoke-patches will be dotted around the battlefield.
Rain
It is unknown, if Rain has any gameplay effect as of right now.
Cold
Coldness might result in metal armors that are in close proximity to share a 'zap'. Those zaps apply very minor damage, and might also be spotted from enemy players with ease. It is currently unknown whether Cold has any other gameplay effects as of right now.