PRECIPITATION IN WINTER STORMS IN CALIFORNIA 
125) 
SAN RAFAEL RIDGE o i 
Sle 
2 RK a 2 9 
q w el 
lof 8 
+ re - 
° = ° 
\ wy SANTA YNEZ VALLEY < 
i‘ 
ons’ + 
de) T 
hee STABLE 
+4 
N (a) 
N fe) 
6 AS COASTAL RIDGE : 
° 
NY o 
4 cls 
o < ° ° 
w - + 
x w KEY 
oO 2 " © SEEDED 
2 N Lok @ + NOT SEEDED 
=x 
N HF 2 ° 
° S fo) 
c 
a 
6 WY 0.5 CONVECTIVE 
\ COAST Fae ° 
+ 
4 < i ° A 
= + =! 
x INCHES= VI > 
NY (b) 
2 ° | 1 | =x 
Oo 0.5 1.0 1.5 2.0 
N ISLANDS 
° Fie. 3—Comparison of island versus target 
rainfall under stable and unstable storm condi- 
tions 
N 
2 NN : ISLANDS a ah nets _ue 
\N sof ees 1 
: _—TemP-0.P. 1958 | 
6 SS == AIR TEMP °C) | 
S a 
20' ‘22 24 ‘02 ‘o# ‘os’ ‘os i | ee 
FEB. 24 FEB. 25,1958 HT 
Fic. 2—Hourly rainfall averaged over oro- ail 
graphic regions for the low-level stable storm of 
February 24-25, 1958 
complicated example of this structure. Figure 
2 shows the hourly rainfall distribution of this 
storm, over (a) the island control area and four 
east-west strips of target, (b) the coastal plain, 
(c) the first ridge, (d) the valley, then (e) the 
next ridge to the north. The maximum occurs 
in the coastal plain and the first ridge. These 
same storm characteristics have been observed in 
Sweden by Bergeron [1949] and are there dis- 
cussed in illuminating detail. 
Figure 3a shows the scatter diagram of the 
island control stations against the mainland tar- 
get stations for the stable storms of 1958. The 
rain pattern is consistent from one stable storm 
period to another. 
Figure 3b on the other hand shows the scatter 
diagram for the unstable storm periods of the 
same year. Note that the slope of the regression 
TIME -HEIGHT STORM STRUCTURE 
Fre. 4—Time-height cross section over Santa 
Barbara for a typical convective storm of April 
2-3, 1958; broken and solid lines as in Figure 1 
