Doppler Lidar Wind Measurements Around Hurricanes in the 2018-2019 NOAA Hurricane Reconnaissance Programs

While meteorological observations in and near tropical cyclones (TC) have improved in both quality and density, there remains important data-sparse regions that need to be sampled. Instruments flown on the NOAA’s P3 Orion Hurricane Hunter Aircraft such as the Tail Doppler Radar (TDR) provide comprehensive coverage of the wind field in many areas of the TCs with precipitation, however the radar has a difficult time making wind observations where there is no precipitation. This includes significant parts of the TC boundary layer and regions such as moats between the eyewall and outer rain bands or secondary eyewall.

An airborne Doppler Wind Lidar (DWL) is an instrument that has the potential to provide this missing information. A coherent DWL measures the motion of aerosols along a laser beam above or below the aircraft to provide line-of-sight (LOS) velocities which, in turn, are converted to 3-dimensional wind profiles with horizontal spacing of as little as 3 km. In addition, the DWL is able to collect wind measurements down to 100m above the sea surface with vertical resolutions as fine as 25-50 m.

In the 2018 hurricane season, an airborne DWL was flown on the NOAA P3 Orion aircraft (P3DWL) from August 18^th through August 22^th in the Pacific. The NOAA P3DWL measured wind speed and direction (via VAD scans) providing over 1200 boundary layer wind profiles in and around category 5 Hurricane Lane near Hawaii. The intention is to put the ADWL onto the P3 for the 2019 hurricane season.

During this presentation we will discuss the results from the 2018 Lane missions and, hopefully, new 2019 missions. We will show comparisons of the DWL wind profiles with dropsondes and discuss the eventual utility of the data for researchers and at operations centers. In addition, one of the challenges that will be discussed is the discrimination between hydrometeor vertical motion and the attendant air mass velocities captured by the wind lidar.