Warm and humid weather conditions will continue to prevail across most parts of the country due to the easterlies, while the northeast monsoon or “amihan” remains affecting extreme Northern Luzon, the Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) said on Thursday, March 5.

PAGASA weather specialist Chenel Dominguez said the amihan continues to affect Batanes, Cagayan, Apayao, and Ilocos Norte, bringing partly cloudy to cloudy skies with isolated light rains.

Meanwhile, the easterlies, or warm winds coming from the Pacific Ocean, are affecting the rest of the country, resulting in generally fair but warm and humid conditions, especially from noon to afternoon.

Dominguez said isolated rain showers or thunderstorms may still occur in the afternoon or evening due to localized convection.

As of Thursday, PAGASA reported that no low-pressure area or tropical cyclone is being monitored inside the Philippine area of responsibility.

Although the amihan season is not yet over, Dominguez said PAGASA has begun closely monitoring heat index levels in preparation for the approaching warm and dry or “summer” season.

“The heat index is the temperature felt by our body; it is not the actual air temperature. It is the combined effect of temperature and humidity,” Dominguez explained.

She added that more areas are expected to experience higher heat index levels as the country moves closer to the warm and dry season.

PAGASA said a heat index ranging from 27 to 32 degrees Celsius (°C) falls under the “caution” category, where fatigue may occur with prolonged exposure or physical activity and heat cramps are possible.

A heat index between 33 and 41°C is classified as “extreme caution,” where heat cramps and heat exhaustion may occur and prolonged activity could lead to heatstroke.

Meanwhile, a heat index of 42 to 51°C is categorized as “danger,” as heat cramps and heat exhaustion are likely and heatstroke becomes probable with continued exposure.

A heat index of 52°C and above signals “extreme danger,” indicating that heatstroke is imminent.

To prevent heat-related illnesses, PAGASA advised the public to limit outdoor exposure, drink plenty of water, and avoid beverages such as tea, coffee, soda, and alcohol.

The weather bureau also encouraged the public to wear hats, use umbrellas, and wear comfortable clothing when outdoors, and to schedule strenuous activities during cooler parts of the day.