Issued at 11 PM on 01 November 2020, “SIONY” slightly weakened but remained within Tropical Storm (TS) category over the Philippine Sea. TS “SIONY” continued to move west-northwestward before it slowed down significantly and became almost stationary in the next 36 hours. Afterwards, the tropical storm moved generally westward towards extreme Northern Luzon. On 03 November 2020, “SIONY” intensified into Severe Tropical Storm (STS) and reached its peak intensity of 100-110 km/h the next day prior to its landfall or close approach over extreme Northern Luzon. It left the Philippine Area of Responsibility (PAR) on 07 November 2020 and weakened into a Low Pressure Area within 24 to 36 hours due to increasingly unfavorable conditions.
Source: DOST-PAGASA Severe Weather Bulletin