Forecasting a chaotic lake effect

Utah meteorologists call it the “dreaded lake effect” because they have trouble forecasting when and where heavy snow will be produced by cold air sweeping over the warmer Great Salt Lake. Such storms tend to be strongest in the morning, often during rush hour, so detailed forecasts of lake-effect snowfall would be ideal if available the previous night. So-called next-generation forecast models simulate the lake effect in unprecedented detail. But a study by Jim Steenburgh, a professor of atmospheric sciences, provides a sobering assessment how well these computer models can make night-before forecasts of the strength and location of lake-effect snowfall. The models raise false alarms, forecasting intense bands of lake-effect snow when actual snowfall is lighter and not banded. Steenburgh says lake-effect snowfall is mathematically chaotic. He says next-generation forecast models can do better if their shortcomings are addressed and enough computing power is provided to take into account the chaotic nature of the lake effect.

Office: 801-581-8727| Email: jim.steenburgh@utah.edu