MANILA (UPDATED) — Manila Mayor Honey Lacuna-Pangan announced the suspension of face-to-face classes in the city on April 25 and 26 as the heat index is expected to reach dangerous levels. 

The suspension covers classes on all levels in public and private schools on Thursday and Friday.

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"This is due to the forecasted danger heat index level of 44°C according to the Manila Disaster Risk Reduction Management Office," the announcement said. "Schools are advised to shift to asynchronous classes."

In a separate announcement, Puerto Princesa City Administrator Arnel Pedrosa said on-site classes in the capital of Palawan will be suspended from April 25 because of the heat.

"In order not to disrupt classes, implementation of asynchronous classes or modular learning system may be held until this temporary suspension is lifted," Pedrosa said.

Heat index, which takes into account air temperature and humidity, measures how hot an area "feels like". 

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