p. 277
Cold Front:
cold air behind front (often to NW)
abrupt cooling as it passes
Warm Front:
warm air behind front (often to S)
more gradual warming
Stationary front: divides airmasses, but little forward
motion
Occluded front:
cold front “catches up” to warm front
warm sector now only found aloft
less temperature contrast
Vertical displacement along a cold front
COLD FRONT
Infrared Imagery
Radar Imagery
Profile of a warm front
Occlusion sequence
p. 291
Stationary Front
POLAR AIRMASS
POLAR FRONT
SUBTROPICAL AIRMASS
Maturity
Lifting processes and cloud cover
Occlusion
Convergence and divergence
along a Rossby wave
If lows and highs aloft and at the surface are
above one another, the systems will weaken !
Convergence
aloft promotes
the surface
high
Divergence
aloft promotes
the surface
low
Surface
divergence
Surface
convergence
Longwaves
MIGRATE THROUGH
THE LONGWAVE TROUGHS
1
Condensation may
release even more
heat energy for the
storm
2
Differential temperature
advection intensifies the
wave
No temp advection
3
Less upper level
divergence
Relative vorticity
Vorticity through
a Rossby wave
Values of absolute vorticity on a hypothetical 500 mb
map
Temperature variations in the lower atmosphere
lead to variations in upper-level pressure
Example of a midlatitude cyclone
April 15
April 16
April 18
• Flow patterns and large-scale weather
–Zonal height patterns “zonal flow”
Meridional flow pattern
Typical winter midlatitude cyclone paths
What is the term for this early stage in the
life cycle of a midlatitude cyclone?
A. cyclogenesis
B. occlusion
C. maturity
D. senescence
What is the term for this early stage in the
life cycle of a midlatitude cyclone?
A. cyclogenesis
B. occlusion
C. maturity
D. senescence
What is the term for this stage in the
life cycle of a midlatitude cyclone?
A. cyclogenesis
B. occlusion
C. maturity
D. senescence
What is the term for this stage in the
life cycle of a midlatitude cyclone?
A. cyclogenesis
B. occlusion
C. maturity
D. senescence
In which area would overrunning occur?
A
B
C
D
A. A
B. B
C. C
D. D
In which area would overrunning occur?
A
B
C
D
A. A
B. B
C. C
D. D
Which location would have the lowest pressure?
A
B
C
D
A. A
B. B
C. C
D. D
Which location would have the lowest pressure?
A
B
C
D
A. A
B. B
C. C
D. D
Which area would have the greatest
positive relative vorticity?
[insert figure 10-4]
A. 1
B. 2
C. 3
D. 4
Which area would have the greatest
positive relative vorticity?
[insert figure 10-4]
A. 1
B. 2
C. 3
D. 4
Which area would have the
least relative vorticity?
A. 1
B. 2
C. 3
D. 4
Which area would have the
least relative vorticity?
A. 1
B. 2
C. 3
D. 4
To what might divergence
along the jet stream contribute?
[insert figure 10-7]
A. uplift over a surface low
B. sinking air
C. chaotic flow
D. anticyclones
To what might divergence
along the jet stream contribute?
A. uplift over a surface low
B. sinking air
C. chaotic flow
D. anticyclones
What would cause this
surface low to strengthen?
[insert figure 10-11b]
A. a barotrophic atmosphere
B. divergence aloft
C. convergence aloft
D. negative relative vorticity
What would cause this
surface low to strengthen?
A. a barotrophic atmosphere
B. divergence aloft
C. convergence aloft
D. negative relative vorticity
Where is the “dry conveyor belt”
in the diagram?
A
B
C
D
A. A
B. B
C. C
D. D
Where is the “dry conveyor belt”
in the diagram?
A
B
C
D
A. A
B. B
C. C
D. D
Which term best describes the
upper air flow in the diagram?
A. baroclinic
B. zonal
C. meridional
D. mythical
Which term best describes the
upper air flow in the diagram?
A. baroclinic
B. zonal
C. meridional
D. mythical
Which term best describes the
upper air flow in the diagram?
[insert figure 10-15b]
A. baroclinic
B. zonal
C. meridional
D. mythical
Which term best describes the
upper air flow in the diagram?
insert figure 10-15 a]
A. baroclinic
B. zonal
C. meridional
D. mythical