Chapter 11 — WATCH ROUTINES (CONTINUED) 



-45 -40 -35 -30 -25 -20 -15 



10 15 20 25 30 35 40 45 50 55 60 65 70 75 60 65 90 95 100 105 MO 115 

 FAHRENHEIT TEMPERATURE SCALE 



Figure 11-31.— Example of isotherms on the SKEW-T Diagram. 



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PLOTTING THE DIAGRAM 



At some stations the first step in plotting 

 is to trace the data from the previous sound- 

 ing onto the new chart for continuity. This 

 is accomplished by tracing the temperature and 

 dew-point temperature curves only, in black 

 pencil or ink, without transcription of data or 

 circling of any points. Next obtain the upper 

 air data for the station in question, which will 

 generally be received over the teletype and in 



code form. After decoding this message (dis- 

 cussed in the previous chapter) the plotting pro- 

 cedures to be followed are as follows: 



1. LEGEND BLOCK-Fill in station number, 

 station identification, time, date (including month 

 and year), and plotter's last name, initials, 

 and rate. 



2. TEMPERATURE CURVE-For each manda- 

 tory and significant level the temperature will 

 be plotted to the nearest one-tenth degree, with 



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