Mission Science Report

5 a/c COVES mission in tropical cyclone Humberto.

The second "COVES" mission was performed on Hurricane Humberto with the ER-2 and DC-8. NOAA had all three of their aircraft flying, and NOAA 42 and NOAA 43 were coordinated with the NASA aircraft.

Humberto was reduced in strength from the previous day, with a MSLP of 992 mb reported by the NOAA aircraft. The aircraft each made three passes across the storm intersecting the center point, but optimized in such a way to maximize the coverage by the dropsondes released by the aircraft. The plan was to have the DC-8 launch 18 sondes, and the ER-2 12 sondes with a few additional sondes in the eye. After the first pass, the ER-2 was requested to return to JAX because of bad weather there. The ER-2 ended up launching 7 sondes (one in the eye) and the DC-8 23 sondes (2 eye and 3 to fill in for the ER-2). The ER-2 sondes had several failures, and the DC-8 sondes were mostly reliable. Humberto had similar flight level wind structure to the previous day. The storm was embedded in strong southwesterly flow, and anticylonic outflow from the convective region was quite obvious. The warm core in the eye at flight level was fairly weak with only about a 2-3C excess over the surrounding environment. There was a huge cirrus outflow with this storm extending several hundred nm from the storm center.