Doppler Lidar Wind Measurements around Hurricane Maria during the 2017 NOAA Hurricane Reconnaissance Program

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.

The NOAA P3 airborne Doppler Wind Lidar (P3DWL) 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 2017 hurricane season, an airborne Doppler Wind Lidar (DWL) was flown on the P3 Orion (P3DWL) from August 29^th through September 25^th in the Atlantic. The P3DWL measured wind speed and direction (via VAD scans) from the 21^st-25^th September providing over 1400 boundary layer wind profiles in and around Hurricane Maria (2017).

During this presentation we will discuss the results from the 2017 mission, show comparisons of the DWL wind profiles with dropsondes and 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.