Meteorology Air Masses & Fronts

1. MeteorologyAir Masses & Fronts

2. Reference From the Ground Up Chapter 6.6 & 6.7: Air Masses & Fronts Pages 140 - 147

3. Introduction • Giant air masses move around with the winds and rotate around pressure systems to bring different weather to areas. • It’s important to know what types of air masses and fronts exist, how they form, and what kind of weather they will cause

4. Outline • Air Masses • Fronts

5. Air Masses • Large section of troposphere with uniform properties of temperature and moisture in the horizontal • May be several thousand miles across • Takes on properties of surface over which it forms (known as Modification)

6. Classifications • Classifications • Continental Dry c • Maritime Moist m • Arctic Cold A • Polar Moderate P • Tropic Warm T • Main types in North America in winter = cA, mA, mP • Main types in North America in summer = mA, mP, mT

7. Air Masses

8. Fronts • Transition zone between two air masses

9. Fronts • Cold Front • Leading edge of advancing cold air mass • Faster the front, the more severe the thunderstorm

10. Fronts • Warm Front • Trailing edge of retreating cold air mass • Indicated by high to low stratus clouds

11. Other Fronts • Stationary Front • Cold air neither advancing nor retreating • Occluded Front (AKA Occlusion) • Cold front overtakes warm front, lifts warm air up • Trowal (Trough of Warm Air Aloft) • Warm air lifted by occluded front

12. Next Lesson 4.7 – Meteorology Precipitation, Fog & Thunderstorms From the Ground Up Chapter 6.8, 6.9: Precipitation, Fog & Thunderstorms Pages 147 - 154