Chapter 11 — WATCH ROUTINES (CONTINUED) 



Table 11-2.— Standard upper air chart markings 



Element 



Marking 



Interval 



Label 



Where 



Units 



Contours 

 (isoheights). 



Solid black pencil line. 

 (Dashed black pencil 

 line for intermediate 

 interval. ) 



60- meter interval up 

 to 300- mb level. 

 120-meter interval 

 at and above 300 mb. 



* 



Thousands, 

 hundreds, 

 and tens. 



Isotherms 



Solid red lines 



5° C 



* 



Degree 

 Celsius. 



Isodroso therms. 



Very light solid green 

 lines. 



10° C 



* 



Degree 

 Celsius. 



Fronts, highs, lows, 

 troughs, and 

 ridges. 



Standard symbols as 

 shown in figure 

 21-8. 





Same general 

 procedures as 

 surface charts. 





Forecast move- 

 ments. 



Red: Low and trough. 

 Blue: High and 

 ridge. 



6hr > 



12hr=^ 





At present 

 location, 

 pointing in 

 direction of 

 forecast 

 movement. 







24 hr Xi> 



(Black) 





Past movement 

 (centers). 



®, 



d ®' 

 (In ink. ) 





At past 

 position. 





Isotachs 



Short dashed green 

 lines. 



20 knots 



At edges of 

 chart— around 

 closed axes. 



Knots. 



Jetstream 



Thick solid purple 

 line with arrowhead. 



Minimum wind speed 

 of 50 knots 



Along axis of 

 maximum 

 wind speed. 





Tropopause 



(Black pencil. ) 





Where ob- 

 served. 





Thickness lines. 



Dashed, black lines 



60-meter 





Thousands, 

 hundreds, 

 and tens. 



Advection arrows. 



Cold— Blue arrow. 

 Warm— Red arrow. 



At every upper and 

 lower contour inter- 

 section. 







Rise and fall lines. 



Rise— Solid blue pencil 



lines. 

 Fall— Solid red pencil 



lines. 

 (Connecting points of 



equal rise or fall. ) 

 Zero— Purple. 



60-meter 



* 



Meters 



Rise and fall centers. 



Same as movement 

 (centers). 









♦At edges of chart and around closed systems, usually at the top and/or bottom of the closed 

 Isopleths. 



NOTE: Miscellaneous isopleths, such as potential temperature lines or tropopause isopleths, may 

 be drawn in the manner of contours when they are the primary features and contours are not used 

 in that particular analysis. 



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