The 00:00 UTC rawinsonde report from
Fernando de Noronha, Brazil
(below) indicated that the tropical tropopause level was probably located near the 100 hPa pressure level
(at a height of 16,649 meters, or 54,623 feet), where the minimum temperature was
-77.7º C. The presence of cloud top IR brightness temperatures colder than -80º C on the METEOSAT-9 imagery suggests that many of the strongest thunderstorm updrafts were penetrating the tropopause — and such overshooting thunderstorm updrafts have been known to initiate strong gravity waves aloft that have generated moderate to severe turbulence.