The heat index in two provinces of Luzon hit 46 degrees Celsius, the state weather bureau recorded on Wednesday.

The highest heat index was in Aparri, Cagayan and Dagupan City in Pangasinan around 2 pm.

Patrick Del Mundo, Pagasa weather forecaster, warned the public in areas with high heat index of possible "heat cramps, heat exhaustion and heat stroke".

"They (public) should always drink water, wear light colored clothes and avoid direct exposure to sunlight during day time," he said.

The next highest heat index of 45 degrees Celsius was recorded in Casiguran, Aurora at 2 pm, followed by 43 degrees Celsius in Catarman, Northern Samar at the same time.

Other areas with high heat index recorded of 42 degrees Celsius were in Guiuan, Eastern Samar; Masbate City, Masbate; San Jose, Occidental Mindoro and Sangley Point in Cavite all at 2pm, Butuan City, Agusan del Norte at 5pm; Davao City, Davao del Sur at 4pm; and Dipolog, Zamboanga del Norte at 11 am.

Del Mundo said based on their record the highest heat index of 47 degrees Celsius was recorded at 2pm on March 25, 2023 in San Jose, Occidental Mindoro.

He said the high heat index is expected to last until the first week of May.

"During the second week of May there are high chances of thunderstorms in the afternoon," he added.

According to the climatological division of Pagasa, the highest heat index monitored last year was recorded in Dagupan City in Pangasinan with 55 degrees Celsius at 2pm of May 1, 2022. Robina Asido/DMS