124 AIR MASS ANALYSIS 
cs = Rear limit of Acu opacus attached to the primary Cold Front 
Cs = Occlusion Point 
ce; = Fore limit of Nbst formed on the primary Warm Front Surface 
cs = Fore limit of Ast formed on the primary Warm Front Surface 
@; = Fore limit of Cist formed on the primary Warm Front Surface 
Vertical Section D: 
d: = Fore limit of Ast of the next disturbance 
d: = Rear limit of Acu opacus attached to the wave disturbance of the 
Cold Front 
ds = Cold Front of the wave disturbance on the primary Cold Front 
d: = Warm Front of the wave disturbance on the primary Cold Front 
ds = Fore limit of Nbst on the Warm Front Surface of the wave disturbance 
ds = Rear limit of Nbst formed on the primary Cold Front Surface 
d; = Primary Cold Front 
ds = Limit of drizzle before the primary Cold Front 
dy = Limit of drizzle behind the primary Warm Front 
di = Primary Warm Front 
di: = Limit of drizzle (= rear limit of Nbst) before the primary Warm Front 
di = Fore limit of Nbst formed on the primary Warm Front Surface 
dis = Fore limit of Ast formed on the primary Warm Front Surface 
du. = Fore limit of Cist formed on the primary Warm Front Surface 
A THREE-DIMENSIONAL PICTURE OF THE WARM- 
FRONT OCCLUSION (lL. = low pressure center 
at the ground; L’= low pressure center 
in the warm air aloft; P= the point 
where the upper cold front pierces the 
2, z-plane). 
