MANILA, Philippines — Nearly a month's worth of rain fell in six hours today as Tropical Storm Ketsana slammed ashore in the Philippines, killing five people and stranding thousands on rooftops in the capital's worst flooding in more than 42 years.

The government declared a "state of calamity" in metropolitan Manila and about two dozen storm-hit provinces, said Defense Secretary Gilberto Teodoro, who heads the National Disaster Coordinating Council. That allows officials to withdraw emergency money for relief and rescue.

President Gloria Macapagal Arroyo had to take an elevated commuter train to the disaster council office to preside over a meeting because roads were clogged by vehicles stuck in the floodwaters.

Two people were reported killed in suburban Muntinglupa and three others in Quezon city, said deputy presidential spokesman Anthony Golez. He gave no details.