Fronts

1. Fronts March 2011

2. Bell Work • 1. Using a psychrometer, figure the relative humidity in the classroom. • 2. Yesterday, there were high, curl or “wispy” clouds in the sky, indicating a change in the weather. What type of clouds were they? • 3. Which type of air mass may cause the type of weather we are seeing today? • 4. If thunderstorms were to roll in Mt. Gilead later on this afternoon, which kind of clouds would you expect to see?

3. Bell Work • What do the following letters represent in an air mass? (m) (c) (P) (T)

4. Cloud Quiz • 1. stratus • 2. cirrus • 3. cumulus • 4. nimbo (nimbus) • 5. alto • 6. strato • 7. cirro

5. Front • 1. Front- • Boundary that forms when two different air masses meet

6. Map symbol Weather Conditions Cold fronts move fast, producing thunderstorms, heavy rain, or snow Cold air meets and moves a warm air mass Cold Front

7. Map symbol Weather Conditions Nimbostratus clouds, Usually drizzly rain After the front passes, weather is clear and warm. Warm air meets and over-rides a cold air mass Warm Front

8. Map symbol Weather Conditions Cool temperatures with large amounts of precipitation Fast moving cold air mass overtakes a slower moving warm air mass. Warm air ↑ Occluded Front

9. Map symbol Weather Condition Usually drizzly After the front passes, weather is clear and warm Cold air mass meets a warm air mass with little horizontal movement Stationary Front