Emerging Airborne Observational Strategies for Improved Tropical Cyclone Track and Intensity Prediction

Two recent Tropical Cyclone (TC) Forecast Demonstration Projects (TCFDP) have utilized new and innovative technologies and targeted observing strategies for improving TC track and intensity forecasting: 1) Sensing Hazards with Operational Unmanned Technologies (SHOUT, 2015-16) and 2) East Pacific Origins and Characteristics of Hurricanes (EPOCH, 2017). Both of these projects share the objective of complementing legacy G-IVSP RD-94 dropsonde observational capability of the mid- and upper troposphere with improved NRD-94 mini-dropsonde observing strategy deployed from Global Hawk UAV vehicles in the lower stratosphere.

A new dropsonde targeting strategy was developed at UASUNY using ECMWF ensemble forecasts in the 48-72 hour period to estimate regions of high observational uncertainty for prediction of track and intensity. The Global Hawk patterns flown in both of these projects used this strategy in developing dropsonde deployment locations for each flight. This paper describes how the resulting dropsonde locations compared with these regions of maximum uncertainty. In addition, the locations of these high uncertainty regions relative to key environmental and storm relative features is described and depicted using GOES visible and IR imagery, microwave imagery and concurrent airborne and land-based radar imagery.

Speculation will be presented on the relationship between operational HWRF track and intensity prediction with and without the high-altitude dropsonde observations. In addition, introduction of new RD-41 dropsonde technology for the 2018 hurricane season will be summarized.