A Comparison of Radar and Satellite Climatologies in Detecting Lake Effect Precipitation over Lake Michigan

Lake-effect (LE) precipitation occurs when cold air passes over warm bodies of water, inducing atmospheric destabilization and subsequent precipitation. Previously, visible satellite imagery has been utilized to create a climatology of LE cloud bands (i.e., Laird et al. 2017). However, visible imagery is not available during nighttime hours, provides no confirmation of precipitation, and can not detect LE under synoptic cloud regimes. Due to these limitations, radar is a potentially interesting alternative, despite its own constraints. This presentation will establish a LE radar climatology over Lake Michigan and compare its results to the visible satellite climatology established by Laird et al (2017). This radar climatology was conducted for 16 cool seasons (October-March) spanning 2006 through 2022 using data from the National Centers for Environmental Information. The occurrence of LE, band type, and synoptic precipitation were recorded for each day. Overall, radar and satellite were in agreement on the detection of a majority of LE bands. When the two climatologies were in disagreement, there tended to be more instances of radar detection only. Results also indicate that the discrepancies between the climatologies are most likely due to synoptic clouds masking LE on visible imagery. While nighttime LE does occur, it does not appear to be the main reason for satellite’s underestimate of LE.