Author of report: Mike Douglas

Mission Number: 030115I

Type of Mission: low-level jet

Start time of Mission(UTC): 2003/01/15 13:04

End time of Mission(UTC): 2003/01/15 20:20

Flight was carried out from northern Bolivia to Paraguayan border to describe weak low-level jet suspected to be present from model guidance available. Ferry to a point near 11.2S 65.8 W was followed by horizontal sawtooth pattern extending southeastward across eastern Bolivia with vertical porpoising to sample both along-jet structure and vertical variations of the jet. About 20 ascents and 20 descents were carried out as part of the porpoising. Main problem was that the jet was weaker than expected; winds greater than or equal to 20 kts were confined to very close to the Andean foothills. Strongest winds very close to Santa Cruz, rapidly weakening with distance away from the foothills. Some storms were sought out near the Paraguayan border near the end of the flight but ground clutter made developing a pattern about the storms difficult. Flight was successful in obtaining many profiles of a weak jet; may be useful for model validation.