Chapter 11 — WATCH ROUTINES (CONTINUED) 



(I) ANALYSIS FEATURE (II) SYMBOL ON STATION CHARTS 



21 Quasi-stationary front at the surface, 

 undergoing frontolysis 



22 Occluded front at the surface, under- 

 going frontolysis 



COLOR 



HBHBRBRBRBRBRBRBR Red(R) 



///////////////// « nd , R , 



blue (d) 



///////////////// P^le 



(III) SYMBOL ON CHARTS TO BE 

 REPRODUCED IN ONE COLOR 



Black and White 



23 Cold front aloft, undergoing fron- 

 tolysis 



24 Warm front aloft, undergoing fron- 

 tolysis 



25. Quasi -stationary front aloft, under- 

 going frontolysis 



26 Occluded front aloft, undergoing 

 frontolysis 



27 Instability line (non-frontal line 

 along which squalls or other evidences 

 of marked instability exist) 



//////////////// 

 //////////////// 



Blue 



//////////////// 

 //////////////// 



RBRBRBRBRBRBRBRB D . , m 



//////////////// ""j ( J 



//////////////// Blue (B) 

 RBRBRBRBRBRBRBRB 



//////////////// 

 //////////////// 



Red 



Purple 



d-CS-C^-Cl-Cl 



£^_-^_o_-<^_o 



Purple 



28 Trough line 



Brown 



29 Ridge line 



30 Shear line or surge line 

 (tropical analysis) 



31 Line of convergence 

 (tropical analysis) 



32 Line ol divergence 



(tropical analysis) 



33 Center of tropical cyclonic circu- 

 lation (strongest wind Beaufort Force 

 5 to 11 inclusive) 



34 Tropical hurricane center (strong- 

 est wind Beaufort Force 12 or greater) 



©©©©©© Brown ©©©©©© 

 + + + + + + Brown + + + + + + 



§ 

 * 



Red 



Red 





35 Intertropical convergence zone 



i / > f ' ~r Red i i i i i zn. 

 NOTES 



1. In symbols 1-12 inclusive, Column III, barbs may be separated mors than shown, but a continuous Una 

 will always be drawn through the bases of tha barbs 



2. In symbols 13-18 inclusive, Column III, tha barbs will always b* separated and will always ba drawn 

 without a connecting Una. 



3. In symbols 19*26 inclusive, Column HI, tha barbs may ba spaoad a greater distance than shown hara, 

 but tha length of tha dash batwaan barbs should aqual tha spaoa batwaan tha dash and each adjacent 

 barb. 



4. In symbol 35, Columns II and III, tha spacing batwaan tha continuous Unas will normally ba about % 

 inch, but may ba graatar whan tha intertropical convergence rone Is broad. 



Figure 11-9.— Weather analysis symbols — Continued. 



209.305.1 



letter H, and label all low-pressure centers with 

 a red block letter L. 



After the final analysis is complete, the 

 following become apparent: 



1. Isobars representing different pressure 

 values never touch or cross. 



2. Isobars never split. 



3. The spacing between isobars is directly 

 related to the wind speed. The closer the iso- 

 bars are to one another, the stronger the wind; 

 the wider the space between isobars, the weaker 

 the wind. 



205 



