Summary
An early season tropical low developed in the central Indian Ocean on 18 November and reached tropical cyclone intensity the following day near 6°S 94°E. Bertie moved to the south southwest reaching category 3 intensity on 21 November and then category 4 before weakening late on 23 November as it moved west of 90°E into La Reunion's area of responsibility and was renamed Alvin . There was no known impact from Bertie .
For more details see the TC Bertie Report (pdf)
Track and intensity
All times in WST.