Typhoon SONAMU was formed in Sulu Sea. The formation of a typhoon at this time of year, January 3, 09 UTC, is the fourth earlist formation since 1951, only after
Typhoon 195501,
Typhoon 195701,
Typhoon 197901. However, as the
typhoon season, this should be considered as the continuation of the previous season. As
Typhoon Bopha of the last year, this typhoon also passed Mindanao Island, and then became a typhoon.