Author of report: Mike Douglas

Mission Number: 030201I

Type of Mission: heat low

Start time of Mission(UTC): 2003/02/01 11:57

End time of Mission(UTC): 2003/02/01 20:32

This flight was conducted to describe flow and thermodynamic conditions around heat low over northern Argentina. An effort was also made to describe the northerly jet forecast to be close to the Andean foothills. Flight involved a porpoising ferry south to the Argentinean entry point at 24S, 60W; thereafter the flight was modified from originally filed track to focus on observations closer to foothills and measure the region near the heat low center - analyzed to be near 30S, 66W. Faster than normal fuel consumption due to high temperatures over the region (surface temps up to 42C) forced small adjustments to track and flight profile to complete mission. A segment of ferry at 480 mb during the return permitted porpoising on the approach to Santa Cruz. This gives soundings separated by almost 7 hours. Preliminary looks at the data show that the air at 850 mb was about 7-10C warmer near the southern end of the track compared with Santa Cruz. Only small differences were evident at 700mb, except over the basin south of Andalgala (east of Catamarca) where the 700 temp was 4 C warmer than elsewhere. Northerly flow was present over most of the region, with low-level winds reaching 30 kts near 26S. Low-level winds became southeasterly over a small region near La Rioja (southern end of the flight track).