Narrative:

At FL380 passing the north shore of jamaica; aircraft experienced light to moderate turbulence for 10-15 seconds. The sky was clear; you could see all of jamaica and most of cuba. The radar was on; set -1; full gain; 160 mile scale. No weather was depicted. The same radar setting was used all flight and we circumnavigated many areas of weather over south america with light chop the worst ride of the night for small periods of time. We started to pick up some st elmo's fire on the windscreen and a little green appeared on the right side of the radar within 5 miles of aircraft. We started a left turn and entered light turbulence with occasional moderate turbulence. It lasted 10-15 seconds. Rainfall could be heard on the airframe. Out the front of the aircraft all was clear. The turbulence ended and it was smooth air from there to miami. The flight attendants reported the carts in the aft galley had all fallen over. Minor bruises and stiffness from bracing their positions so they wouldn't be tossed about by the turbulence was reported. The RPM turbulence part of wsi did not show any turbulence in the area.

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Original NASA ASRS Text

Title: Air carrier flight crew reported clear air turbulence that caused minor injuries to the flight attendants.

Narrative: At FL380 passing the north shore of Jamaica; aircraft experienced light to moderate turbulence for 10-15 seconds. The sky was clear; you could see all of Jamaica and most of Cuba. The radar was on; set -1; full gain; 160 mile scale. No weather was depicted. The same radar setting was used all flight and we circumnavigated many areas of weather over South America with light chop the worst ride of the night for small periods of time. We started to pick up some St Elmo's fire on the windscreen and a little green appeared on the right side of the radar within 5 miles of aircraft. We started a left turn and entered light turbulence with occasional moderate turbulence. It lasted 10-15 seconds. Rainfall could be heard on the airframe. Out the front of the aircraft all was clear. The turbulence ended and it was smooth air from there to Miami. The flight attendants reported the carts in the aft galley had all fallen over. Minor bruises and stiffness from bracing their positions so they wouldn't be tossed about by the turbulence was reported. The RPM turbulence part of WSI did not show any turbulence in the area.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.