Trough of tropical depression outside PAR triggers rain in Palawan

MANILA, Philippines – A low pressure area (LPA) outside the Philippine Area of Responsibility (PAR) developed into a tropical depression at 2 pm on Saturday, December 21.

As of 3 pm, the tropical depression was located 900 kilometers southwest of southwestern Luzon, moving east northeast at 15 kilometers per hour (km/h).

It has maximum sustained winds of 55 km/h and gustiness of up to 75 km/h.

The Philippine Atmospheric, Geophysical, and Astronomical Services Administration (PAGASA) said in a briefing on Saturday afternoon that the tropical depression only has a slim chance of entering PAR.

But the trough or extension of the tropical depression is causing heavy rain in Palawan, and isolated to scattered rain and thunderstorms in Mindanao.

Another source of rain is the shear line, which is affecting Calabarzon, Bicol, the rest of Mimaropa, Visayas, and Dinagat Islands.

The shear line refers to the point where cold air from the northeast monsoon or amihan converges with the easterlies or warm winds from the Pacific Ocean.

PAGASA issued the following advisory for rain from the trough of the tropical depression and the shear line at 5 pm on Saturday:

Saturday afternoon, December 21, to Sunday afternoon, December 22

• Heavy to intense rain (100-200 millimeters): Quezon, Camarines Norte, Oriental Mindoro, Palawan
• Moderate to heavy rain (50-100 mm): Laguna, Occidental Mindoro, Marinduque, Romblon, Catanduanes, Camarines Sur, Albay, Sorsogon, Masbate, Antique, Aklan, Capiz, Iloilo, Northern Samar, Eastern Samar, Samar

Sunday afternoon, December 22, to Monday afternoon, December 23

• Heavy to intense rain (100-200 mm): Camarines Norte, Camarines Sur, Catanduanes, Albay, Sorsogon
• Moderate to heavy rain (50-100 mm): Quezon, Masbate, Oriental Mindoro, Marinduque, Romblon, Palawan, Aklan, Capiz, Northern Samar, Eastern Samar, Samar

Monday afternoon, December 23, to Tuesday afternoon, December 24

• Moderate to heavy rain (50-100 mm): Quezon, Camarines Norte, Camarines Sur, Catanduanes, Albay, Sorsogon, Masbate, Oriental Mindoro, Marinduque, Northern Samar

Floods and landslides are likely.

Meanwhile, the northeast monsoon is affecting the rest of Luzon, where periods of rain are expected.

The Philippines’ last tropical cyclone was Tropical Depression Querubin, which brought rain to Mindanao and the Visayas. It developed last Tuesday, December 17, but weakened into an LPA on Wednesday, December 18.

The LPA that used to be Querubin dissipated at 2 am on Saturday. – Rappler.com