Over-sebaceous activity on melanin-rich skin
Shine, congestion and breakouts — oil production pushed up by heat and humidity rather than by anything you are doing wrong.
What it looks like
Visible shine through the T-zone, pores that look enlarged, congestion you can feel more than see, and a blemish-prone pattern that returns in the same places.
Why it happens in the tropics
Heat and humidity drive the sebaceous glands harder. Oil mixes with sweat and the day's dust, sits in the pore, and the pore stretches to hold it — which is why the same climate that suits the skin in December troubles it in March.
What actually helps
Clear the congestion without stripping the barrier. Strip it and the skin answers by making more oil, which is how most people make this worse while trying to fix it.