ELMIRA, N.Y. (WETM) – Often in the wintertime 18 Storm Team Meteorologists use the term “upslope snow”, but what does it mean and why is this so important? This phenomenon actually has a large impact of snow totals across the Twin Tiers and it all depends on two things: mountains and wind direction. It is in play all year but much more noticeable with snow left on the ground.
As a storm system or disturbance moves in, moist and warm air hits the mountain and is forced upwards. As this air cools it condenses and rain falls on the same side of the mountain. During the summertime this can form rain showers but during the wintertime this effect can enhance snow totals and really allow it to pile up on the same side of the mountain.
As the cooler air passes over the mountain, it sinks and warms again as it descends. This allows for the air to dry out on the other side of the mountain and precipitation to stop. This is what inhibits snow totals during the winter time. Snow totals or rain showers forming are all dependent on the direction of the wind. With storms tracking up from the south this isn’t a factor too much here in the Twin Tiers. However, with lake effect snow blowing from the north and northwest, this can really help snow pile up on the side of the mountains facing the Great Lakes.