SEVERE WEATHER

1. SEVERE WEATHER

2. Cloud classification High clouds (above 6km) Cirrocumulus clouds – puffy, high clouds Cirrus – thin, wispy Cirrostratus – cover the sky. Can give us solar and lunar halos.

3. Halo around the sun through a cirrostratus cloud.

4. Mid-level clouds (1.8 to 6 km) Have prefix alto- No halo Altocumulus clouds Altostratusclouds

5. Low-level clouds (ground level to 1.8km) Stratus clouds – low to ground, blanket-like Nimbostratus – low clouds that accompany precipitation Stratocumulus – low puffy clouds

6. Clouds with vertical development Cumulus clouds Cumulonimbus clouds - thunderstorms

8. Unusual cloud shapes Lenticular altocumulus Mammatus clouds

9. Ripples – indicate instability in the atmosphere.

10. Fog – Moist air is cooled and condenses. Advection fog – moist air moves over a cool surface. Radiation fog – radiative heat loss cools the ground. Nearby air is cooled, leading to condensation. Morning fog is often radiation fog.

11. Steam fog – occurs on cold days when a body of water is warmer than the air.

12. Table 12.3

13. Fig. 12.6 Billion-dollar climate and weather disasters, 1980-2005

14. Fig. 12.8 DROUGHT Stratford, TX in 1935

15. Fig. 12.7 Hot, dry conditions caused by high pressure ridge

16. Fig. 12.9 Drought map of the United States in 1934 – DUST BOWL

17. Fig. 12.10 HEAT WAVE Temps in Chicago, July 1995

18. Fig. 12.11 Blue areas cooler than usual 10°C hotter than July 2001 European heat wave, July 2003

19. Table 12.4

20. Fig. 12.12 Mid-latitude cyclones

21. Fig. 12.13

22. Fig. 12.14

23. Fig. 12.15 BLIZZARDS AND ICE STORMS

24. Fig. 12.16

25. Fig. 12.17

26. Freezing rain – occurs when water freezes as soon as it touches an object rather than in the air

27. Fig. 12.19 THUNDERSTORMS

28. Fig. 12.18 Warm, buoyant air mass is rising

29. Fig. 12.20 Early stage of thunderstorm growth. Updrafts creating tall, moisture-rich clouds

30. Fig. 12.21 A mature thunderstorm Downdrafts creating wind and heavy rain.

31. Table 12.7 DERECHO – widespread, powerful straight-line winds. Can be as damaging as a small tornado.

32. Fig. 12.22 Number of days with thunderstorms per year

33. Fig. 12.23 Localized areas of high rainfall, central TX

34. Fig. 12.24

35. Fig. 12.25

36. LIGHTNING

37. Fig. 12.27 Number of lightning deaths, 1959-2004

38. Fig. 12.28 Number of lightning deaths by month 1959-1980

39. Table 12.5

40. Table 12.6

41. Fig. 12.29

42. Fig. 12.30

43. Fig. 12.31

44. Lightning isdeadly! • Lightning Safety • Take shelter inside a building. • Do not use a land-line phone or electrical equipment like computers, etc. • Stay away as much as possible from anything that has pipes (sinks, bathtubs, showers, toilets). • DO NOT take shelter under a tree or the overhang of a tall building. Go inside. • If you’re on a lake, get to shore and find shelter immediately.

45. Fig. 12.32 TORNADOES Tornado near Dimmitt, TX 1995

46. Fig. 12.33

47. Fig. 12.34

48. Fig. 12.35

49. Table 12.8

50. Table 12.9