I just finished a flight with a friend hosting a multiplayer session.  We both were flying PMDG 737 aircraft and both running Active Sky (same version).  We were flying from PAFA to PAJN.  He was seeing scenery with snow coming down and I was only seeing Clouds.  We both thought that we should be seeing the same type of weather as I was flying in a session set up by him.  I believe that the wind directions were also different.  Does any one have any idea why this was happening? 

Make sure your settings in ASN are identical, you both could have different visibility settings, different cloud settings, and one of you could have been on historical rather than live weather. Also you could be using different ASN servers and one might not have updated. Are you both using 10 minute download settings in the asn menus? Also flying in the USA make sure the cloud CB setting is uncehcked.