Most massive floods in southern Thailand are brought by low pressure, southwest monsoon that occurs for a long duration with quite high cumulative rainfall. The southern Thailand has experienced many floods over the last decade, with the five most severe ones in 2010, 2011, 2016, 2017 and January 2019. Among all of the floods throughout these 10 years, the flood caused by the tropical storm “PABUK” in January 2019 was the only event that was directly affected by storm.
A comparison of “PABUK” with those of some historical severe storms that attacked southern Thailand such as Tropical storm “HARRIET” in 1962, Typhoon “GAY” in 1989, Typhoon “LINDA” in 1997, and Typhoon “DURIAN” in 2006 reveals that HARRIET, PABUK and LINDA attacked southern Thailand while they were a tropical storm, but PABUK had slightly higher wind speed. Although DURIAN was a typhoon, it became depression when attacking southern Thailand. Gay was the only typhoon in history that attacked Thailand while it was still a typhoon.
The cumulative rainfall volume caused by PABUK is approximately 96 mm., which is the least rainfall volume with the fewest rainy days and the smallest flood area of approximately 62 sq.km. covering 16 provinces and 4 deaths, the lowest death toll. It is very different from the five historical severe flood events. The wind speed of PABUK caused the highest wave in the gulf of Thailand, which was estimated to be 3–5 meters high, but it caused neither severe flood events nor massive damage because of quick and efficient evacuation.