Issues with filming

As I mentioned in my 'weather' post, conditions for filming are becoming less and less suitable, as we are currently experiencing heavy snow and have forecasts for even more snow this week.
It is now a large possibilty that we may have to adapt our script to fit in with the weather, so we have begun to think about outdoor scenes that may have to be changed.
In the first scene of our storyboard, we tilt the camera down from the sky to meet gareth who is drinking. This would actually look quite good in the snow, as the sun may reflect off of falling snowflakes, supporting the idea that the setting is 'nice'. However, we do not want to distract the viewers attention away from gareth, because we have already drawn their eyes to the snow.
But we do not want to run into problems with continuity, with it snowing heavily in one scene and then sunny the next. Therefore, if we were to film in the snow, we may have to film each scene quickly while the snow lasts. Also, if we discovered a mistake with our filming, it may be too late to change it as the snow would probably have gone. So we may have to just 'leave' the mistake, which is obviously not something we want to do.