Boeing is alerting airlines to a possible engine icing problem with Boeing 747-8 and 787 Dreamliner aircrafts.
The alert is due to the GE-powered engines that are experiencing icing problems while in flight, not on the ground.
Boeing told CNN that pilots should "keep the planes at least 50 nautical miles from storms that may contain ice crystals until General Electric can make improvements to the "GEnx" engines."
A statement from Boeing said that only a small number of engines have had a problem with ice crystals.
GE is said to be working to fix the problem.