1. Wind & Weather Basics March 2014

2. Weather is always changing ! Constant movement of air Changes in moisture

3. Air Mass Large body of air that has the same properties as the surface over which it develops. – Cold, Hot- Wet, Dry These air masses move across the U.S. & collide with each other creating fronts ….….

6. Types of Air Masses

10. Weather Maps

18. Tuesday & Wednesday

22. Isotherms

23. Isobars

27. http://www.aos.wisc.edu/~aalopez/aos101/wk 3/wk3Pcont.jpg

30. Cloud Formation

34. Condensation level = bottom of the clouds

35. Clouds may form by Forceful Lifting May occur when air goes up the side of a mountain Also occurs when air is lifted during storms

36. Advective Cooling Occurs when wind blows warm, moist air over a cold area such as a lake or ocean.

38. Types of Clouds

40. Fog = low stratus cloud

42. How does weather affect you? Directly – Rain – floods/drought – Snow – closes school – Ice – no power – Tornado – destructive Indirectly – Drought – food prices go up – Freeze in South – fruit is destroyed – Cold Weather – oil & gas prices go up

43. What determines what the weather will be today? Air pressure Wind Temperature Humidity

44. Wave Cyclones Low pressure areas Start to rotate counterclockwise Bad weather Thunderstorms & rain

45. Air Pressure Low Pressure Few molecules in the air “sucks in” bad weather

46. Hurricanes = Tropical cyclones Also known as typhoons Speeds in excess of 120 km/hr

47. Thunderstorms

48. Tornadoes

49. Anticyclones High pressure areas Dry/clear weather Droughts "High pressure is good; sunny weather occurs when the pressure is high. Skies are blue, winds are light and it never rains when the barometer soars."

50. Air Pressure High Pressure Lots of molecules in the air “pushes away” the bad weather

51. Complete Venn Diagram for High & Low Pressure Systems

52. 03/22/2001 - Updated 02:02 PM ET Source: USA TODAY research by Chad Palmer, Graphic by John He

53. 03/22/2001 - Updated 02:36 PM ET Source: USA TODAY research by Chad Palmer, Graphic by John Herne

54. Occluded Fronts 2 cold air mass meet Pushing up the warm air that is blocked in-between. 03/22/2001 - Updated 02:29 PM ET 03/22/2001 - Updated 02:29 PM ET

55. Stationary Front

56. Each Front causes precipitation Along each front warm air is pushed upward, cooled in the atmosphere, and becomes saturated

57. Types of Fronts

58. Start here on Wednesday

59. Weather Instruments & forecasts

60. Anemometer  Measures wind speed

61. Wind Comes from North => Cold Comes from South => Warm Fast or Slow ???

62. Weather Radar = Doppler Radar

63. Measuring air pressure with a barometer

64. Humidity Hot air can hold more water vapor Cold air is drier & causes static electricityin winter Measured with a psychrometer, hygrometer, or a

65. Relative Humidity The amount of water vapor in the air compared to how much it could hold. ex.) 50%, 20% Saturated means 100% Measured with a psychrometer.

66. Radiosonde = package of weather instruments

69. Climate: predictable weather patterns