1. CLOUD FORMATION There are 3 things required for clouds to form:
Water vapour
Change in temperature or pressure
Condensation nuclei (dust, smoke, etc)

2. CLOUD CLASSIFICATION Low-level = less than 2km
Mid-level = between 2 and 7km
High level = greater than 7km
Alto = mid-level
Cirrus = wispy, high-level clouds
Stratus = featureless blanket
Nimbus = rain cloud
Cumulus = fluffy rolling clouds

3. STRATUS CLOUDS Low-level clouds, closest to Earth No definite form
Often cover whole sky
Usually associated with moist weather

4. Cumulus Clouds Higher altitudes than stratus White fluffy masses
Often associated with fair weather
May cause heavy rainfall

5. Stratocumulus Clouds Low-level clouds
globular masses or dark and light rolls
Common during winter
Form in the wake of cold front

6. Nimbostratus Clouds Low-level Shapeless, irregular edges
Thick, block sun
Bring steady precipitation

7. Altocumulus Clouds Mid-level clouds Cover sky
Globular masses and rolls
Associated with rain or thunderstorms

8. Altostratus Sheets of blue and gray that cover most of the sky
Sometimes thick enough to block the sun, leaving a light area in the sky
Appear a few hours ahead of a warm front, and indicate a decrease in pressure.

9. Cumulonimbus Clouds Range in altitude
Tall. Top in cold upper air with warm base. (anvil shaped)
Called “thunderheads”
From the warm base lightning, thunder and precipitation originate

10. CIRRUS CLOUDS High altitude clouds Ice crystals Thin, wispy, feathery
Distant storm or change in weather

11. Cirrocumulus Clouds Very high altitudes Formed by ice crystals
“mackerel sky”- small, globular, white masses or ripples
Approaching warm front or storm

12. Cirrostratus clouds
a layer of cirrus clouds that spreads across the sky
make the sky pale or white in appearance
indicate approaching precipitation

13. CLOUD QUIZ SHOW

14. For each of the following pictures:
identify the type of cloud and
indicate the characteristics that allowed you to make this identification

15. 1.

16. 2.

17. 3.

18. 4.

19. 5.

20. 6.

21. 7.

22. 8.

23. 9.

24. 10.

25. Altocumulus midlevel. globular.1.
Altocumulus midlevel. globular.

26. whole sky. no defined form.2.
Stratus
whole sky. no defined form.

27. 3.
Cumulus
fluffy

28. 4.
Cirrus
high level. wispy.

29. Cirrocumulus “mackerel sky”5.
Cirrocumulus “mackerel sky”

30. whole sky. no definite shape.6.
Stratus
whole sky. no definite shape.

31. Cumulonimbus anvil shape7.
Cumulonimbus anvil shape

32. Nimbostratus dark rain cloud. sky cover.8.
Nimbostratus dark rain cloud. sky cover.

33. fluffy. lots of sky cover.9.
Stratocumulus
fluffy. lots of sky cover.

34. 10.
Cumulus
fluffy