According to the latest storm/low pressure information from the Philippine Atmospheric, Geophysical and Astronomical Services Administration, at 8:00 p.m. on December 20, Low Pressure 12b was at about 4.3 degrees north latitude, 111.0 degrees east longitude, 1,575 km west of Western Mindanao, Philippines.
At 2:00 a.m. on December 21, Low Pressure 12b was outside the Philippine Forecast Area (PAR) and had a moderate chance of becoming a tropical depression in the next 24 hours.
According to the US Joint Typhoon Warning Center (JTWC), low pressure Invest 96W (low pressure 12a named after the Philippines - weakened from tropical depression Querubin) is currently located in the northern Sulu Sea and is creating unorganized showers and thunderstorms.
The circulation of the low has become unclear and adverse environmental conditions will likely prevent any redevelopment before it is absorbed by Low 12b (Invest 98W) early next week. The 7-day chance of this low developing is 0%.
Regarding Low Pressure 12b in the southern East Sea, which JTWC calls Invest 98W, JTWC said that the circulation of the low pressure appears to be becoming clearer. Although the low pressure is located near the equator, environmental conditions appear favorable for further development. The low pressure may intensify into a tropical depression on December 22 or 23 when it begins to move slowly north to the north-northeast.
The low will turn northwest early next week as it interacts with and absorbs 96W, and by December 24 or 25, upper-level winds are likely to become extremely unfavorable for further development.
The system is likely to bring widespread heavy rainfall to parts of Vietnam, Malaysia, Indonesia and Brunei over the next few days. The chance of the low pressure system strengthening over the next 7 days is at 50%.
Meanwhile, according to the weather forecast of the Vietnam National Center for Hydro-Meteorological Forecasting, on December 21, the low pressure trough in the south has an axis at about 4-7 degrees north latitude connecting with the low pressure area at 1:00 a.m. this morning located at about 3.9-4.9 degrees north latitude, 110.8-111.8 degrees east longitude.
At Huyen Tran station, there were strong winds of level 7, gusting to level 9; Phu Quy island had strong winds of level 7-8; Truong Sa island station had strong winds of level 6-7, gusting to level 8.
Forecast for the day and night of December 21, in the northern East Sea (including the Hoang Sa archipelago), there will be strong winds of level 6-7, gusting to level 8-9. Rough seas. Waves of 3-5m.
From Binh Dinh to Ca Mau, between the East Sea and the western sea area of the South East Sea (including the west of Truong Sa archipelago), wind level 6, sometimes level 7, gusting to level 8-9. Rough sea. Waves from 3-5 m high.
From Thua Thien Hue to Quang Ngai, wind level 6, gusting to level 7-8. Rough sea. Waves 2-4 m high.
In the evening and night of December 21, the Gulf of Tonkin has wind force 5, sometimes force 6, gusting to force 7-8. Rough sea. Waves 1-2.5 m high.
During the day and night of December 21, the southern East Sea (including the Truong Sa archipelago) will have scattered showers and thunderstorms. During thunderstorms, there is a possibility of tornadoes and strong gusts of wind of level 7-8.
