010921 Radar and Sounding Operation Status

The radar operated continuously without problems.

Convective activity today was largely dominated by the passage of the 
tropical disturbance at the northern end of the radar domain 
(starting around 05Z).  Effects from this disturbance in the vicinity 
of the ship were limited to convection initiated along outflow and 
other boundaries.  Echos became intense after 12Z with several cells 
extending over 15 km and 30 dBZ contours to > 10-12 km.  However, it 
appeared that most of the activity associated with the wave passage 
was well north of the radar sampling domain.  A persistent cyclonic 
vortex was present in the long range scans throughout the afternoon 
(18-21Z).  After 18Z, a noticeable change in echo movement was 
apparent with features now moving off to the N-NE, in agreement with 
the flow to the rear of the wave.  The disturbance produced 
significant 2nd trip echos in the radar data throughout the day.

With regard to the soundings, the 20Z launch did not return winds. 
All other sondes returned wind and thermodynamic data through the 
troposphere.  The most significant feature of the sonde data was the 
appearance and strengthening of a dry inversion layer between 500-400 
mb throughout the day.  This layer was also characterized by SW'erly 
flow.