WSR-88D monitoring of shallow lake-effect snowstorms over and around Lake Ontario: Simulations of improvements using lower elevation angles

Currently, National Weather Service (NWS) WSR-88D radars do not operate below +0.5 deg. Consequently, shallow lake-effect snowstorms over and around Lake Ontario pose a detection (and warning) challenge for the Buffalo, NY, NWS Forecast Office. Limited measurements in the lower portions of the storms preclude reliable quantitative precipitation estimation (QPE) in much of the coverage area.

This presentation will show how we use simulated scanning strategies to investigate how much detections and QPE would improve using lower elevation angles for the three closest New York State WSR-88Ds: Montague (KTYX), Buffalo (KBUF), and Binghamton (KBGM). Canadian radars at King City and Franktown on the north side of the lake—that operate as low as –0.1 and 0.0 deg, respectively—also are considered.

The Montague radar is located east of Lake Ontario on top of the Tug Hill Plateau 520 m above the lake. Using current scanning strategies, 2-km-deep snowstorms are detectable to a range of only 100 km from the radar (covering the eastern quarter of the lake). The Buffalo radar covers the western half of the lake. Being farther from the lake, the Binghamton radar covers snowstorms that extend southeastward from Lake Ontario.

Simulations show that, when the lowest elevation angle for KTYX is decreased to –0.4 deg, the range of detection of 2-km-deep snowstorms increases from 100 to 220 km. Lowering the lowest elevation angle for KBUF and KBGM to +0.2 deg increases the coverage area (2 km above the surface) by about 60%. Lowering the scanning strategies for these three radars and operating in conjunction with the Canadian radars, shallow lake-effect storms would be detected over the entire lake and surrounding coastal regions and reliable QPE information would be available over nearly the entire region.