The Philippine Atmospheric, Geophysical and Astronomical Services Administration (Pagasa) on Tuesday declared the onset of the dry season in the country.

In a statement, Pagasa administrator Vicente Malano said the state weather bureau has observed gradual increase in temperature in many parts of the country.

"Weather chart and numerical model output analyses indicate the weakening of Siberian High Pressure and the establishment of the North Western Pacific High Pressure Area during the week," he explained.

He added there was also a shift in the wind pattern from northeasterly to easterly.

Malano said the public should expect daily weather will be warmer and drier in most parts of the country due to the dominance of the ridge of high pressure area and the easterlies.

With these observations, Pagasa officially declared the end of northwest monsoon or amihan season.

"This would also signify the start of the dry season," he said.

Filipinos refer dry season as "summer" since there is no summer season in any tropical climate countries.

Pagasa advised the public to minimize heat stress and keep themselves hydrated.

The state weather agency said some isolated rainshowers and thunderstorms may be expected mostly in the afternoon or evening.

According to Pagasa's climate monitoring and prediction section, the highest temperature recorded so far was from Cotabato province at 36.7 degrees Celsius Monday.

For 2017, the highest temperature recorded was 38.3 degrees Celsius in Echague, Isabela. Ella Dionisio/DMS