Snowed Out: Lake-Effect Snow and the Creek Cleanup

A Cleanup on Hold

1The Cattail Creek Stewards, a volunteer group from Lakeview Middle School, planned to pick up trash along their creek on a Saturday in mid-November. Cattail Creek winds through a town on the eastern shore of Lake Erie and empties into the lake. The town and its weather stations are made up, but the weather they show is common there in late fall. On Friday evening, group leader Mr. Tomasz Brzezinski sent a message: the forecast called for "lake-effect snow" overnight.

2An air mass takes on the temperature and humidity of the place where it forms. Behind a cold front, a cold, dry air mass from central Canada had spread over the Great Lakes, and the wind was blowing from the west, along the length of Lake Erie. In November, the lake water still holds heat from the summer. On Saturday morning, the water near the lake buoy was 10 °C.

3Sixth grader Lena Kowalczyk woke up to deep snow. At 7 a.m. she looked up the readings from five stations that lie in a line from west to east, along the path of the wind. One reading shows how much water vapor the air held, in grams of water vapor in each kilogram of air (g/kg).

4Lake-effect snow usually falls in long, narrow bands, often 10 to 40 km wide, that line up with the wind. Under a band, snow can pile up quickly, while a town just outside it may see sunshine. Lena kept an hourly log at the creek for the rest of the day.