Amihan, Shear Line, ITCZ to bring rains over long Undas weekend
Parents and guardians pick up young pupils from an elementary school in Quezon City amid moderate rain on Thursday afternoon, September 17, 2026. Jonathan Cellona, ABS-CBN NewsMANILA — Three weather systems will bring rains over the long Undas weekend, PAGASA said in its special weather outlook.
The Northeast Monsoon, or Amihan, will affect parts of Luzon, while the Shear Line will bring rains over the eastern sections of Luzon and Visayas.
The Shear Line forms where the Amihan and the Easterlies converge.
Meanwhile, the Intertropical Convergence Zone (ITCZ) will affect parts of Southern Luzon, Visayas, and Mindanao.
On Friday, October 30, cool weather and isolated light rains are expected in Batanes, Cagayan, Apayao, Abra, and Ilocos Norte due to Amihan.
Scattered rains will affect Isabela, Aurora, and Quezon due to the Shear Line. The ITCZ will bring scattered rains to Central Visayas, the Zamboanga Peninsula, Northern Mindanao, Caraga, Southern Leyte, Siquijor, and Negros Oriental.
On Saturday, October 31, Amihan will bring cloudy skies with rains over Batanes, Cagayan, and Isabela.
The strengthening Amihan will push the Shear Line southward, bringing scattered rains to Aurora, Quezon, the Bicol Region, and the Samar provinces.
Palawan, Tawi-Tawi, Basilan, and the Zamboanga Peninsula will continue to experience scattered rains due to the ITCZ.
On Sunday, November 1, All Saints’ Day, scattered rains from the Shear Line will affect the Bicol Region, Quezon, and Aurora, while the ITCZ will continue to affect Palawan and western Mindanao.
By Monday, November 2, the Shear Line and ITCZ may dissipate.
However, Amihan will bring generally fair weather over most of Luzon, although isolated light rains will remain possible.
Metro Manila and the rest of the country will experience generally warm and humid weather, with isolated rain showers or localized thunderstorms in the afternoon or evening from Friday to Sunday.
Amihan may reach Metro Manila and parts of CALABARZON by Monday.
Meanwhile, the tropical cyclone internationally named “In-fa” may briefly enter the Philippine Area of Responsibility (PAR) next week.
Currently a super typhoon, “In-fa” was located more than 3,900 kilometers east of Central Luzon as of 5 p.m. Wednesday, based on data from the Japan Meteorological Agency.
It had maximum sustained winds of 185 kilometers per hour and gusts of up to 230 kph, moving westward at 20 kph.
The cyclone will be assigned the local name “Samuel” once it enters the PAR on Monday or Tuesday.
It will remain far from the Philippine landmass and will not directly affect the country’s weather.
The public is advised to continue monitoring updates on this weather disturbance as the forecast will still change.