Geographically located in Northern Trinidad, Tunapuna–Piarco shares its borders with the regions of San Juan–Laventille to the west, Couva–Tabaquite–Talparo to the south, the Borough of Chaguanas to the south-west, Sangre Grande to the east and the Caribbean Sea to the north.

It features the country's two highest mountain peaks, El Cerro del Aripo at 3,084 feet and El Tucuche standing at a soaring 3,070 feet, which both tower the north of the region and the Northern Coast of Trinidad forming a part of the Northern Range.

The Northern Range which covers 25% of the land area of Trinidad stretches the entire Northern Coast of Trinidad from the regions of Diego Martin and San Juan–Laventille in the west and through Tunapuna–Piarco to Sangre Grande in the east, is located to the north of the region and is the largest mountain range in the country.

Cloud Forest and heavy fog covers the mountains to the north while the rest of the region experiences cloudy skies and heavy rainfall with moderately cool daytime temperatures during the rainy season and dry spells and abundant sunshine in the dry season.

The region as well as the rest of the country does not fully observe winter, spring and autumn but experiences similar characteristics of the seasonal changes.