A cyclone is a rotating low-pressure weather system that forms over warm ocean waters and has organized thunderstorms but no fronts. There are three main types of cyclones: tropical cyclones, which form in the tropics; extratropical cyclones, which form outside the tropics in response to instability; and tornadoes, which are rapidly rotating columns of air extending from thunderstorms to the ground. Cyclones form as warm, humid air rises over the ocean, condenses into clouds and releases heat, causing more warm air and surrounding winds to be drawn inward toward the area of low pressure. The Philippines experiences an average of 20 typhoons annually due to its location in the Pacific typhoon belt.

1. CYCLONE Formation
Presenter: Neil Jarrett G. David

2. Did you know…
A cyclone is a general term for a weather system in which
winds rotate inwardly to an area of low atmospheric pressure.
Types of Cyclones
 Tropical Cyclones
 Extratropical Cyclones
 Tornadoes
Tropical cyclone is a rotating low-pressure weather system
that has organized thunderstorms but no fronts. They form
over warm ocean waters.
Extratropical cyclones are low-pressure systems that form
outside of the tropics in response to a chronic instability of
the westerly winds.
Tornado is a rapidly rotating column of air extending
downward from a thunderstorm to the ground.

3. How a Cyclone Form
1
Humid, warm air forms over the
warm ocean surface
2Water vapor rises with warm air
3 Water vapor rises, cools, and
condenses into cloud
4
Condensation releases heat
into the air. Heat evaporates
more water.
5 Warm air keeps rising and wind
from the surroundings move in

4. In our Country (Philippines)
Philippines is visited by an average of 20 typhoons every year, five of
which are destructive because it is located along the typhoon belt in the Pacific.
The classification of tropical cyclones according to the strength of the
associated winds as adopted by PAGASA as of 01 May 2015 are as follows:
 TROPICAL DEPRESSION (TD) - a tropical cyclone with maximum sustained
winds of up to 61 kilometers per hour (kph) or less than 33 nautical miles per
hour (knots).
 TROPICAL STORM (TS) - a tropical cyclone with maximum wind speed of 62
to 88 kph or 34 - 47 knots.
 SEVERE TROPICAL STORM (STS) - a tropical cyclone with maximum wind
speed of 89 to 117 kph or 48 - 63 knots.
 TYPHOON (TY) - a tropical cyclone with maximum wind speed of 118 to 220
kph or 64 - 120 knots.
 SUPER TYPHOON (STY) - a tropical cyclone with maximum wind speed
exceeding 220 kph or more than 120 knots.
Source: https://www.pagasa.dost.gov.ph/information/about-tropical-cyclone