Author of report: Ed Zipser

Mission Number: 030122I

Type of Mission: MCS

Start time of Mission(UTC): 2003/01/22 19:04

End time of Mission(UTC): 2003/01/23 03:26

SALLJEX Research Flight NOAA43 Flight ID 030122I MCS mission. This appeared to be a successful mission for observing the rapid growth of a strong MCS in northern Argentina, its evolution into maturity, and wind and thermodynamic conditions ahead of the leading edge and in one instance behind the bow echo. This flight planned to sample LLJ conditions in southeastern Bolivia and Paraguay enroute to anticipated convective development, either in Paraguay or northern Argentina. The leg ESE from VVI had many soundings from 300 m AGL to 10-12000 ft in northwest flow of about 20 knots, turning to northerly winds in Paraguay. Luck was with this flight in many ways, as the best convective development was a short distance south of our planned entry point into Argentina , and only 30 minutes before crossing the border Jim McFadden called the aircraft on the satphone to say that the long-awaited clearance had been granted. From 2130-0200 we obtained almost continuous radar and environmental data on a rapidly developing MCS. The strongest growth took the form of intersecting line s not far from 25S 60 W. The original line was W-E moving north, but the line oriented NNW-SSE became dominant and formed a squall line-bow echo during the flight. Early runs on the east side of that line passed close to some storms reaching 20 km with 40 dBZ echoes to about 16 km. Several wall clouds and frequent C-G lightning were visible. After an hour on this side, we circled westward around the main system to sample the rear side, which had rather little stratiform precip behind the bow echo. Soundings to 12 or 14K were made ahead and behind the system. We then worked back to the northeast (leading edge) side, did several more soundings, and obtained additional Doppler runs on the north side. The line was followed northwest to near the Bolivia-Paraguay-Argentina intersection, and then several soundings were taken enroute back to Viru Viru along 62.5W.