Storms Overview

1. Storms Overview

2. Background Basics • Air around the planet constantly moves in response to the rotation of the planet. • Cold air is more dense than hot air and thus when these two types of air masses collide the hot air rises. (cold air is generally dryer) • When the warm air is forced upwards it creates a lower pressure region. • Cold air moves in to fill the region left behind by the warm air and thus the cycle continues. • Low pressure area moves with the Earth’s atmosphere which rotates west to east. • In the northern hemisphere, wind rotates in a counter-clockwise manner around a storm center. (powered by the Coriolis effect)

3. Background Basics • A storm ends when either the warm or the cold air dissipates and things return to normal (equilibrium is re-established). • The meeting of cold polar air and warm equatorial air causes the areas of different pressure.

4. Background Basics THUS… A STORM FORMS IN RESPONSE TO DIFFERENCES IN AIR PRESSURE DRIVEN BY THE MOVEMENT OF COLD AND WARM AIR!

5. equilibrium • The atmosphere likes equilibrium and dislikes pressure differences. • The greater the pressure difference, the stronger the wind.

6. Indicators of a Storm: • Strong wind • Thunder • Lightning • Heavy precipitation • Cumulonimbus clouds

7. Types of storms • Ice Storm • Blizzard • Snowstorm • Ocean Storm (strong winds, often associated with capsized vessels) • Firestorm (strong winds, often associated with forest fires) • Tornado • Hailstorm • Tropical Cyclone • Thunderstorm • Squall • Dust Devil • Windstorm

8. How do you classify a weather event as a storm? • Meteorologically speaking: winds greater than a 10 on the Beaufort scale. • In common, everyday language a storm has a different meaning.

11. Ice storm, blizzard and snowstorm

12. Ocean storm and tropical cyclone

13. firestorm

14. tornado

15. hailstorm

16. Windstorm and squall

17. Dust devil