MANILA - Occasionally heavy rains on Wednesday will hit Bicol region as it faced the threat of lahar from Mount Mayon, state weather bureau PAGASA said.

Potentially dangerous mud flows or lahar would flow down the slopes of Mayon if the ash and debris it has been spewing since the weekend mixes with rainwater, the Philippine Institute of Volcanology and Seismology warned.

• Lahar threatens communities along Mayon's slope

Bicol, Metro Manila, Central Luzon, Calabarzon and Mimaropa will experience heavy rains due to the tail end of a cold front, PAGASA meteorologist Shelly Ignacio told DZMM.

At 5 a.m., PAGASA raised an orange rain warning alert over the Bicolono towns of Albay, Camarines Sur, Camarines Norte, Catanduanes, and Sorsogon.

The warning, which is the second highest in a 3-step system, means that areas will experience 1 to 2 hours of rains that could trigger possible floods and landslides.

Meanwhile, a low pressure area outside the Philippine area will also dump occasionally heavy rains in Visayas and Mindanao, Ignacio said.

The weather disturbance is unlikely to intensify into a storm, she said.

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