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APPENDIX C
FRONTAL WEATHER
PRACTICAL EXERCISE
TITLE: FRONTAL WEATHER
TERMINAL LEARNING OBJECTIVE (TLO): At the completion of this PE, the student will:
ACTION: Plan a flight mission IFR or VFR in accordance with weather conditions.
CONDITION: In a classroom environment.
STANDARD: IAW FM 1-230.
EVALUATION: At the end of this PE, the instructor will conduct an after action review (AAR) concerning
the PE.
RESOURCE REQUIREMENTS: Students need a pen or pencil and this PE.
SPECIAL INSTRUCTION: None.
PROCEDURES:
1. This is a written exercise covering the instruction you received on frontal weather.
2. Record your answer on the PE handout.
3. All work must be done on your own. If your raise your hand, the instructor will provide assistance.
4. Upon completion of this PE, compare your answers with the solution provided. You will then be able
to identify any weak areas to overcome prior to the examination.
5. If unable to complete this PE during the allotted class time, complete it prior to the next class.
6. Clear up any misunderstandings with the instructor.
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QUESTIONS
1. A front is
a. a ridge of high pressure.
b. the boundary between air masses of different densities.
2. What are the four types of fronts (any order)?
a.
b.
c.
d.
3. Identify the following symbols used on weather charts as cold front, warm front, stationary front, and
occluded front.
A
a. ____________
B
b._____________
C
c. _______________
D
d. ______________
4. The frontal inversion of any front always slopes over the __________ (warm/cold) air, and the
precipitation associated with it normally occurs in the ________________________ (warm/cold) air.
5. The surface position of a front may extend for hundreds of miles along the surface.
a. True
b. False
6. The type air masses most often associated with fronts in the US are __________________ and
_________________.
7. Fronts lie in ____________ (high/low) pressure troughs between air masses.
8. The primary factors affecting frontal weather are ________________, _________________, and
________________.
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9. Cloud formations associated with fronts are produced by _______________ cooling.
10. Four discontinuities (differences) across a frontal boundary are (any order)-a.
b.
c.
d.
11. Define a cold front. ________________________________________________
______________________________________________________________________
12. The coldest air will always be ______________ (ahead/behind) a cold front.
13. The average speed of movement of a cold front is about ____________, therefore, it will have a
_____________ (steep/shallow) slope.
14. Because of the average slope of the cold front, if sufficient moisture is available in the warm air,
_________________ (cumuliform/stratiform) clouds normally will form. If clouds form, the typical
band of violent weather will be about ______________ miles wide.
15. The general direction of movement of a cold front is toward the ________, and the winds ahead of
the front are generally from the ________. Behind the front winds are typically from the
____________.
16. A violent band of thunderstorms called ___________ _____________ may form ahead of
____________ (slow/fast) moving cold fronts.
17. Define a warm front. __________________________________________________
________________________________________________________________________
18. Warm fronts lie in troughs of low pressure and normally extend _______________
(eastward/westward) of the low pressure center.
19. The average slope of the warm front has a ratio of ______________, and always slopes over the
_____________ (cold/warm) air mass.
20. The winds ahead of a warm front are generally from the ______________ (what direction) and the
winds behind the front are from the ______________ (what direction).
21. Warm fronts normally move toward the __________ (what direction) at an average speed of
__________ knots.
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22. According to the diagram below, you are approaching a __________ (warm/cold) front from the
__________ (warm/cold) air side.
CI
CS
AS
NS
ST
__________________________________________________________________________________
23. In the cold air under the warm front inversion, ___________ (type clouds) and ____________ may
obscure visibility for hundreds of square miles.
24. A major hazard of warm front flying in the winter is freezing rain which will cause _________
(clear/rime) ice formation on an aircraft flying below the inversion level.
25. If the warm air mass involved in the warm front is unstable, what other weather hazard should the
pilot be aware of when flying in warm frontal areas?
___________________________________________________________
26. If you are approximately 200 miles ahead of the surface position of a warm front, the inversion layer
should be about ___________ feet above the surface.
27. If your destination is in a warm frontal area, an important element of preflight planning should be
selection of __________________________, and fuel consumption.
28. Define a stationary front. ___________________________________________
_______________________________________________________________________
29. The weather associated with a stationary front will normally be similar to that of a _______________
(cold/warm) front.
30. Open waves often develop from ______________ fronts.
31. Open waves may develop into ______________ (warm/cold/occluded) fronts.
32. An _____________ front develops when the faster moving cold front of an open wave overtakes the
slower moving warm front of the wave.
33. The two types of occluded fronts are _______________________ and
____________________________.
34. When the air behind the cold front is colder than the cool air under the warm front of the wave, a
_____________ (warm/cold) front occlusion may occur.
35. With a cold front occlusion, there is always an upper ______________ (cold/warm) front.
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36. A warm front occlusion forms when the air under the ___________________ front is the coldest of
the air masses involved.
37. The low pressure system associated with the occlusion normally moves in a _________________
(easterly/westerly) direction and the most violent weather occurs in the early stages of
development __________ to __________ miles north of the apex of the three fronts.
38. What type of occluded front forms when an advancing cold air front overtakes a retreating cool air
front? ______________________________
39. If an occluded front symbol on a weather map is an extension of the cold front symbol, it is a
___________ type occlusion and if an extension of the warm front symbol, it is a ____________
type occlusion.
40. All fronts have temperature inversions.
a. True
b. False
41. Label the blanks on the diagram.
42. Label the blanks on the diagram.
43. Label the blanks on the diagram.
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44. Label the blanks on
the diagram.
45. Label the blanks on the
diagram.
46. Label the blanks on
the diagram.
47. Indicate with arrow the wind direction associated with the frontal diagram below.
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48. The frontal system depicted indicates an
____________ ____________ frontal system.
49. The frontal system depicted indicates a
__________________ _______________ type frontal
system.
50. The above symbol would indicate that the coldest air is at position _____________.
FEEDBACK: After completion of the PE, the instructor will conduct a critique/after action review.
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APPENDIX C
FRONTAL WEATHER
PRACTICAL EXERCISE SOLUTIONS
1. b.
2. cold, warm, stationary, occluded
3. a.
b.
c.
d.
cold
warm
occluded
stationary
4. cold, cold
5. a.
6. polar, tropical
7. low
8. speed and slope; moisture content of the warm air; stability of the warm air
9. adiabatic (only if enough moisture is available to produce clouds)
10. a.
b.
c.
d.
temperature
moisture
pressure
winds
11. The leading edge of an advancing mass of cold air.
12. behind
13. 25 knots, steep
14. cumuliform, 50 miles
15. southeast, southwest, northwest
16. squall lines, fast
17. The trailing edge of a retreating mass of cold air, with warm air moving in to replace it.
18. eastward
19. 1:200, cold
20. east or southeast, southwest
21. northeast, 15 knots
22. warm, cold
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23. stratiform clouds and fog
24. clear
25. embedded thunderstorms
26. 5,280 feet
27. an alternate airport
28. a front moving between zero to less than 5 knots
29. warm
30. stationary
31. occluded
32. occluded
33. cold, warm
34. cold
35. warm
36. warm
37. easterly, 50 to 100
38. cold occlusion
39. cold, warm
40. a.
41.
42.
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43.
44.
45.
46.
47.
48. Open wave
49. Cold occluded
50. A.
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