Bay-Effect Snow

Bay-effect snow is most commonly know as lake-effect snow. The effect occurs in many places but is best known in the Great Lakes. Snow is produced in the winter when cold, Arctic winds move across long expanses of warmer lake, bay, or ocean water, providing energy and picking up water vapor which freezes and is deposited on the lee shores. The same effect over bodies of salt water is called ocean effect snow, or sea effect snow. Bay-effect snow produces narrow & intense bands of precipitation, which can deposit heavy snowfall amounts in a short period of time. If the air temperature is not low enough to keep the precipitation frozen, it falls as rain. Lake-effect snow forms by significantly cooler air moving across a significantly warmer body of water. Here's a few ingredients that help produce bay-effect: fetch, wind shear, and upstream moisture.

Fetch: the length in which an air mass moves across a body of water.

Wind Shear: is important because the more wind shear the further the bay-effect will be able to travel over land. The less wind shear the larger the precipitation totals will be along the leeward shore. Also wind shear plays a factor in squall lines, which are heavy bands of precipitation, weak directional shear help intensify the squall lines.

Upstream moisture: High relative humidity levels allow the air mass to pick up more condensation over the lake quicker and in larger amounts.

Bay-effect snow is more common during the later fall months and early winter months. Between Novermber, December and early parts of January.
The bodies of water get much cooler during the months of Febuary to April, so the chance of Bay-Effect Snow is a lot less.