Tropical revolving storm Flashcards
Tropical revolving storm
also known as a tropical cyclone, is a rotating, low-pressure system that forms over warm tropical waters, bringing strong winds, heavy rain, and potential flooding.
TRS precondition
Large body of warm water: ≥ 26.5°C throughout a sufficient depth of water
Unstable atmosphere: with a deep layer of instability Moist mid-troposphere
≥ 500 km from the equator: for a sufficient amount of Coriolis
Pre-existing near-surface disturbance: At least a weakly organized system with sizeable spin and low-level inflow
Low magnitude vertical windshear: ≤10 m/s, between the ocean’s surface and the upper troposphere
TRS stages development
TRS Stages of Development
Stage 1. Tropical Disturbance. TS over the tropics typically 200 nm in diameter moving
westward, lasting for > 24 hours. They have no closed wind circulation
Stage 2. Tropical Depression: First appearance of lowering pressure and organised circulation in the centre of the TS. Winds of 17-33 kt
Stage 3/4. Tropical Storm/Severe Tropical Storm: A circular rotating appearance, with
sustained wind 34-63 kt. It is assigned a name
Stage 5. Tropical Cyclone/Hurricane/Typhoon: Surface pressure continues to drop. Sustained wind speed >63 kt and the TRS is fully developed. The pronounced rotation around the central core eventually forms an eye and the surrounding eye wall
