A small whirlwind formed briefly inside the oval of Mangaldan National High School in Pangasinan.

In a video taken by students, a small funnel of wind can be seen spinning across the school grounds while some students shouted in surprise. The whirlwind later faded after a few moments.

Samanta Bautista, a Grade 11 student, said the incident happened around 1 p.m. while they were waiting for their teacher.

“Nagku-kwentuhan kami ng mga kaklase ko tapos anlakas na ng hangin. Sumara ‘yung bintana namin, akala nga namin nabasag. Pumasok sa loob ng classroom mga plastic, mga dumi,” the student said.

School officials said similar incidents have been recorded in the area several times before, usually during the month of March.

Eduardo Castillo, principal of Mangaldan National High School, said the school ensured the safety of students immediately.

“Ang epekto lang naman may mga pumasok na alikabok sa mga classroom pero safe naman lahat,” Castillo said.

According to the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA), whirlwinds or tornadoes can form when warm air meets moist air from above, often associated with strong thunderstorms.

A whirlwind that forms over land is called a tornado, while one that forms over water is known as a waterspout.