Lake Enhancement VS. Lake Effect Showers

Written by: Brian Neudorff

I made a comment this morning that seemed to make a few people worried. The term I used was "Lake Enhanced Showers." The reason this made people nervous was that I was also talking about the chance of wet snow mixing in with rain shower later today and tonight.

I can certainly understand how hearing the words "Lake," "Enhanced," and "Snow"in a forecast can make people a little edgy, especially in October. The good news I wasn't talking about snow, I was talking about rain. So what does lake enhancement mean, and how does it differ from lake effect?

If you have lived through a winter along the Great Lakes then you know about lake effect. In the simplest of terms, lake effect is when cold air moves over a large warm lake that provides energy and water vapor to produce showers. Most common is lake effect snows but if the air temperature is not below freezing then the showers will fall as rain. All of the moisture for the showers comes from one source the lake.

Lake enhancement occurs when showers produced from moisture off the lake compliments showers produced by a larger scale storm system (synoptic). In most lake enhanced situations, conditions for lake effect are marginal but the synoptic storm helps destabilize and moisten the air to push conditions over the threshold. If a lake enhanced situation occurs where enough moisture and instability over the lake exists on its own, you can really get hammered with heavy snow or rain.