This scene takes place in a cold harsh winter. Suddenly the PC's see a snowstorm at the horizon gaining on them, they end up in a snowstorm. This snowstorm is really an air elemental, but invisible to the PC's (the best you can use is the Wind Walker from the MC-annuals, volume one) so they can hardly hit is because it's all over them. If the DM is pissed off he can put some wood, weapons or other objects in the storm to weaken the PC's even more. This encounter can be used to take away some item's the PC have and of which the DM don't want them to have. You can also use this as an introduction of a new (N)PC, which was blew along in the storm.