6 BULLETIN 1155, U. S. DEPARTMENT OF AGRICULTURE. 
In 1913, 1914, and 1915 the precipitation was above normal 
(normal for a 49-year period is 23.01 inches); in 1917, 1918, 1919, 
and 1921 the precipitation was far below normal, while in 1916 and 
1920 it was slightly above normal. The average precipitation for 
the 9-year period from 1913 to 1921 was 21.67 inches. The months 
of greatest precipitation are December, January, and February. 
Little or no rain falls during June, July, and August. The average 
monthly precipitation in inches at the Biggs Rice Field Station from 
1913 to 1921, inclusive, is shown graphically in Figure 2. 
Heavy continuous rains in October and November may result in 
serious losses to rice growers in the valley. In the fall of 1920 only 
about half of the rice crop was warehoused when the heavy rains 
began on November 7. The remainder of the crop stayed in the 
P/?£C/P/7Xr/OA/ //V //V&/£3 
jA/vv/iffy 
pss/fcs/iffy 
| 2.66 
MAffCH 
mm zoo 
APRfL 
Wk-22. 
M/\y 
WL-8+ 
S£Pr£Af3£# 
\.04- 
O 
.63 
OCr03£7? 
m.73 
/HJS 
03C3Af33/? 
4.73 
Fig. 2.— Average monthly precipitation (in inches) at the Biggs Rice Field Station during the 9-year 
period from 1913 to 1921, inclusive. 
fields until spring, much of it was lost, and that which was salvaged 
was badly damaged. 
Table 4 presents data showing the maximum, minimum, and 
average monthly wind velocity in miles per hour from April to 
October, inclusive, during the 9-year period from 1913 to 1921, 
inclusive. 
The maximum velocity recorded for any month during this period 
was 16.1 miles per hour and the minimum 0.1 mile per hour. The 
average daily velocity ranged from 1.6 miles per hour, in October, 
1921, to 5.3 miles, in May, 1915. 
In general, this section has but little wind, though strong winds 
sometimes blow from the north. These, if very brisk, are known as 
"northers," and are welcome at harvest time because of their effective 
drying qualities. A strong north wind for 24 hours is equal to about 
a week of sunshine for drying purposes. 
