MANILA, Philippines ? (UPDATE) Thirteen flights bound for the Ninoy Aquino International Airport were diverted to the Diosdado Macapagal International Airport in Clark, Pampanga, on Sunday, due to heavy rains and poor visibility at the NAIA.

Two more flights were canceled and seven others were delayed, according to a public advisory issued at 3:30 p.m. by the Manila International Airport Authority, which operates NAIA.

The MIAA said the diverted flights were expected to arrive with the weather improving late Sunday afternoon.

The diverted flights were Southeast Asian Airlines' flight DG-022 from Caticlan, Zest Air's Z2-411 from Busuanga and Z2-303 from Kalibo; Philippine Airlines' PR-301 from Hong Kong and PR-168 from Dipolog; Air Philippines Express' 2P-034 from Busuanga, 2P-266 from Naga and 2P066 from Surigao; Cebu Pacific's 5J-786 from Butuan, 5J-580 from Cebu, 5J-964 from Davao, and 5J-888 from Cotabato; and Singapore Airlines' SQ-910 from Singapore.

They were supposed to arrive between 12 noon and 1:30 p.m. on Sunday. Only one arrived, Z2-303, at around 2 p.m. while only three revised their estimated times of arrival: SQ-910, 4 p.m.; and PR-301 and PR-168, both 3:30 p.m.

The canceled flights are Cebu Pacific's 5J-327, which was supposed to arrive at around 12:30 p.m. and Legazpi and its return trip, 5J-328, which was supposed to leave NAIA at around 3 p.m.