1. Air Masses & Fronts

2. What is an air mass?
a giant bubble of air with the same temperature and humidity throughout
Earth’s surface
’s of miles

3. Air masses are named according to… ____________________________ known as their ____________ .
the area over which they form
source region

4. What is an air mass?
a giant bubble of air with the same temperature and humidity throughout
Earth’s surface
’s of miles

5. Compare the air conditions in the Arizona Desert and the Florida coast.
How would the temperature compare? Why?
How would the humidity compare? Why?

7. Does the air mass form over…
land or water?
land = continental air mass (dry)
ocean = maritime air mass (moist)
a warm area or a cold one?
warm area = tropical air mass (warm)
cold area = polar air mass (cool)

9. There are four types of air masses:
mT – maritime tropical – warm, moist air
mP – maritime polar – cold, moist air
cT – continental tropical – warm, dry air
cP – continental polar – cool, dry air

10. Name the type of air mass that is shown at each of the following locations:3 1
Location 1: mP
Location 2: mT
Location 3: cP
Location 4: cT 4 5 2
Location 5: mT

12. How does a source region affect an air mass?
Air masses get their characteristics from the location where they form, called their source region.
How does a source region affect an air mass?
The source region determines the temperature and humidity of the air mass.

13. Which two air masses affect Michigan the most?

14. cP mT

15. Why does the weather change so often in Michigan?

16. Two very different air masses meet right over our state!cP mT

20. Air Mass Review
Air Mass
Conditions
Name an air mass!

21. Air Mass Review Air Mass Conditions cT warm, dry mT warm, moist mP
cool, moist cP
cool, dry
Which air mass is the lightest?
Which air mass is the heaviest?
mT (least dense)
cP (most dense)

22. the boundary between 2 different air masses
What is a front?
the boundary between 2 different air masses
front
warm, moist mT air
cool, dry cP air
Earth’ surface

23. How are fronts named?
Fronts are named according to the type of air mass blowing into an area.
If a warm air mass is blowing in, we call it a warm front.
If a cold air mass is blowing in, we call it a cold front.

24. What type of front is shown here?
W I N D
front
warm, moist mT air
cool, dry cP air
Earth’ surface
Warm Front

25. Warm Fronts
Warm fronts occur when warm, moist mT air blows over colder and more dense cP air. The warm air cools and the moisture condenses to form horizontal layers of clouds.

26. nimbostratus cloud
mT air
cP air

28. Warm Fronts = overcast skies
Hours or days of gray, overcast (cloudy) skies
On and off gentle rain (nimbostratus clouds)
Pass slowly
Bring warm, humid air
NO SEVERE WEATHER!!!

29. What type of front is shown here?
W I N D
front
cool, dry cP air
warm, moist mT air
Earth’ surface
Cold Front

30. Cold Fronts
Cold fronts occur when cooler, drier cP air scoops up the less dense mT air and forces it to rise straight up. The mT cools and the moisture condenses to form very tall cumulonimbus clouds .

31. mT air
cumulonimbus
cP air

32. Cold fronts produce cumulonimbus clouds, storms, and severe weather!

33. Cold Fronts = storms thunderstorms, lightning, and severe weather
cumulonimbus clouds and heavy rainfall
bring cooler, less humid air
pass quickly
hail, high winds, and/or tornadoes possible

34. After a cold front passes you can expect…
Cooler temperatures
Clearer skies
Fair weather
Drier air – lower humidity
Higher pressure
Rising barometer

35. Warm Fronts on a Weather Map
cool, dry cP air
warm, moist mT air
In which direction is this front moving?

36. Warm Fronts

37. Cold Fronts on a Weather Map
cool, dry cP air
warm, moist mT air
In which direction is this front moving?

39. A B Cold Fronts on the Weather Map
What are the sky and temperature conditions like at city A?
What are the sky and temperature conditions like at city B?

40. Main Types of Fronts:
warm front – warm air blows in bringing overcast skies, gentle rain
cold front – cold air blows in, overcast skies, thunderstorms, severe weather

41. Stationary Fronts

42. Resources

46. http://www. newmediastudio