Tropical Cyclone Outflow and Warm Core Structure as Revealed by HS3 Dropsonde Data

Abstract

Dropsonde data collected during the NASA Hurricane and Severe Storm Sentinel (HS3) field campaign from 16 research missions spanning 6 tropical cyclones (TCs) are investigated, with an emphasis on TC outflow and the warm core. The Global Hawk (GH) AV-6 aircraft provided a unique opportunity to investigate the outflow characteristics due to a combination of 18+-h flight durations and the ability to release dropsondes from high altitudes above 100 hPa. Intensifying TCs are found to be associated with stronger upper-level divergence and radial outflow relative to nonintensifying TCs in the sample, regardless of current intensity. A layer of 2–4 m s−1 inflow 20–50 hPa deep is also observed 50–100 hPa above the maximum outflow layer, which appears to be associated with lower-stratospheric descent above the eye. The potential temperature of the outflow is found to be more strongly correlated with the equivalent potential temperature of the boundary layer inflow than to the present storm intensity, consistent with the outflow temperature having a stronger relationship with potential intensity than actual intensity. Finally, the outflow originates from a region of low inertial stability that extends above the cyclone from 300 to 150 hPa and from 50- to 200-km radius.

Document Details

• Document Type: Pub Defense Publication
• Publication Date: Mar 21, 2017
• Source ID: 10.1175/mwr-d-16-0172.1

Entities

People

• James D. Doyle
• William A. Komaromi

Organizations

• Office of Naval Research
• United States Naval Research Laboratory

Tags

Fields of Study

• Environmental science

Readers

• Atmospheric Science/Meteorology

Technology Areas

• Space