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

7. Warm Front Warm air meets and over-rides a cold air mass 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

8. Occluded Front 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 ↑

9. Stationary Front 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