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.
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 B C D
a. ______b.______c. ______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
______.
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.
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.
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.
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.
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.
APPENDIX C
FRONTAL WEATHER
PRACTICAL EXERCISE SOLUTIONS
1. b.
2. cold, warm, stationary, occluded
3. a. cold
b. warm
c. occluded
d. 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. temperature
b. moisture
c. pressure
d. 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
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.
43.
44.
45.
46.
48. Open wave
49. Cold occluded
50. A.
C-1