Impact Of CYGNSS Data On Hurricane Analyses And Forecasts In A Regional OSSE Framework

The Cyclone Global Navigation Satellite System, or CYGNSS, is a planned constellation of micro-satellites that utilizes existing GPS satellites to retrieve surface wind speed near the satellites' ground tracks. The orbits are designed such that there is excellent coverage of the tropics and subtropics, resulting in better sampling intervals over tropical cyclones than is possible with current scatterometers. Furthermore, CYGNSS will be able to retrieve winds under all precipitation conditions, and over a large range of wind speeds in a tropical cyclone. A regional Observing System Simulation Experiment (OSSE) framework was developed at NOAA/AOML and University of Miami and features a high-resolution regional nature run (27-km regional domain with 9/3/1 km storm-following nests with WRF-ARW) embedded within a lower-resolution T511 ECMWF global nature run. Simulated observations are generated and provided to a data assimilation scheme, which produces analyses for a high-resolution regional forecast model. For data assimilation NOAA's Gridpoint Statistical Interpolation (GSI) is used and the analyses are performed in the parent domain at 9-km resolution. The forecast model is the 2014 operational Hurricane-WRF model with a parent domain at 9-km grid spacing and a single storm-following nest at 3-km grid spacing. Synthetic CYGNSS wind speed data have been created from the nature run, the impacts of the assimilation of these synthetic wind speed data on the forecast of track, and intensity will be shown.