6-11. 



6-12. 



6-13. 



6-14. 



Assume that the surface wind at a weather 

 station is from 090° at 75 knots. How 

 should this be plotted? 



, O-rjy, 



6-15. 



3 O- 

 4. li 



-o 



6-16. 



Learning Objective: Recognize pro- 

 cedures and symbols used for drawing 

 and labeling isobars, fronts, air 

 masses, and weather when making a 

 surface analyses. 



What must you do prior to drawing the past 

 fronts and pressure systems on the current 

 surface chart? 



1. Sketch the isobars lightly on the 

 current chart 



2. Check for obviously erroneous reports 

 on the current chart 



3. Sketch the fronts and pressure centers 

 lightly on the current chart 



4. Revise the previous analysis, as 

 necessary, for reports received after 

 the chart analysis was completed 



What action should you take in connection 

 with a doubtful plot discovered during 

 your preliminary analysis of a weather 

 map? 



1. Check it for accuracy against the 

 original report and retain any 

 usuable portions 



2. Remove it from the weather map and 

 exclude it from further consideration 



3. Discard it as soon as you have deter- 

 mined the cause of error 



4. Discard it immediately 



If the reported wind speeds in three 

 areas of a weather map are: Area A, 

 10 knots; Area B, 20 knots; and Area C, 

 30 knots; the isobars will be 



1. spaced the same in all three areas 



2. closer together in Area A 



3. closer together in Area B 



4. closer together in Area C 



6-17. 



6-18. 



Synoptic observations made at what hours 

 are normally used for the plotting of 

 surface charts? 



1. 0000 and 1200GMT 



2. 0000, 0800, and 1600GMT 



3. 0000, 0600, 1200, and 1800GMT 



4. 0000, 0400, 0800, 1200, 1600, and 

 2000GMT 



If isobars are being drawn on a large 

 weather map, those which are normally 

 drawn last are the ones on that part of 

 the map that 



1. cover ocean areas 



2. represent areas of strong wind 



3. represent the center of a low-pressure 

 area 



4. represent the center of a high- 

 pressure area 



Which of the following analysis procedures 



will be used to complete the basic isobaric 



analysis of a surface chart? 



1. Sketching the isobars and fronts 

 lightly on the chart 



Smoothing out all isobars drawn on the 

 chart and sketching in lightly the 

 positions of the fronts 

 The 2-station analysis method, pro- 

 jecting isobars to the proper posi- 

 tions between stations, and searching 

 downwind for new points for the isobars 

 The 2-station analysis method, pro- 

 jecting isobars to the proper positions 

 between stations, and searching upwind 

 for new points for the isobars 



2. 



3. 



Figure 11A. — Isobars. 



Which of the isobars is NOT urawn cor- 

 rectly? 



1. A 



2. B 



3. C 



4. D 



34 



