precipitation, air masses, and fronts current weather finish precipitation air masses fronts for...
TRANSCRIPT
Precipitation, Air Masses, and FrontsCurrent Weather
Finish Precipitation
Air Masses
Fronts
For Next Class: Read Chapter 7 (pp. 215-227)
Reminder: Exam I next Friday! Review sheet is posted
Moisture Droplets
Figure 7.20
Raindrop and Snowflake Formation
Figure 7.21
Saturation Vapor Pressure
Figure 7.12
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Favorable conditions for freezing rain
Temperature conditions required for formation of
frozen, freezing, and liquid forms of precipitation
Cloud Types and Identification
Figure 7.22
Atmospheric Lifting Mechanisms
Figure 8.6
Orographic Precipitation
Figure 8.9
Orographic Patterns
Figure 8.10
Average Annual Precipitation
What is Rime Ice?
Rime IceA coating of tiny, white, ice particles caused by the rapid freezing of supercooled water droplets on impact with an object.
Rime Ice on Mt. Mitchell
Rime Ice on Beech Mountain
Heavy Rime
Icing on
Mt. Washington
Rime Icing on
Grandfather
Mountain
Snow Particle Photomicroscopy
Graupel
Snow Particle Photomicroscopy
Air Masses
What are the major air mass types and source regions?
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Air Masses
Classified as• Cold (polar, abbreviated as P) or warm (tropical or T)• Dry (continental or c) or humid (maritime or m)
Four basic types• Cold and dry, continental polar (cP)• Cold and humid, maritime polar (mP)• Warm and dry, continental tropical (cT)• Warm and humid, maritime tropical (mT)
Fifth type, arctic (A) air, is dry like continental polar air but colder
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Air Masses
Also differ in stability
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Fronts
Narrow zone of transition between air masses that differ in density• Density differences usually due to temperature
contrasts Warm and cold fronts
• Frontogenesis: fronts form or grow stronger• Frontolysis: fronts weaken