This document discusses cyclones and their formation. It defines cyclones as rotating low-pressure weather systems with inward winds. There are three main types: tropical cyclones, extratropical cyclones, and tornadoes. Tropical cyclones form over warm ocean waters and have no fronts. Extratropical cyclones form outside the tropics in response to unstable westerly winds. Tornadoes are rapidly rotating columns of air extending from thunderstorms to the ground. The document then explains the formation process of cyclones over warm ocean surfaces and discusses classifications of tropical cyclones in the Philippines.

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

6. Reflection
Tropical cyclone constitutes one of the most
destructive natural disasters that affects many
countries around the globe and exacts tremendous
annual losses in lives and property. Its impact is
greatest over the coastal areas, which bear the
brunt of the strong surface winds, squalls, induced
tornadoes, and flooding from heavy rains, rather
than strong winds, that cause the greatest loss in
lives and destruction to property in coastal areas.

7. #IMReady sa Bagyo