9 



never reported a freezing temperature nor one higher than 

 87°F aboard their ships. 



Precipitation is less along the coast than in Los Angeles 

 and lower still over the waters of the continental shelf. 

 There are no continuous records of rainfall over the ocean, 

 but the figures for San Pedro probably give a close approxi- 

 raation (Fig. 3). At one time or another rain has fallen in 

 every month of the year, but the summer months are quit* dry. 

 The average for June is 0.10 inch, for July, 0.01 inch, and 

 for August, 0.05 inch. Even in February, the rainiest month, 

 the average is less than 2.5 inches and the greatest preci- 

 pitation over a 24 hour period produced a mere 3.5 inches. 



Sky Conditions 



Data of the sky conditions on land are available from the 

 U. S. Weather Bureau station at the Los Angeles International 

 Airport and are shown in Figure 4. Even so, these do not 

 represent the conditions prevalent over the coastal waters of 

 Los Angeles. The sky and visibility conditions in Figure 4 

 were compiled from the logs of the Catalina Island steamers 

 and represent an observation period of ten years. 

 January 



Fog is prevalent in January with 27% of the mornings 

 (9 days) having ceilings below 500 feet and visibilities less 

 than \ mile. The fog usually changes to a low overcast or 

 broken clouds by 1100 hours. Slightly more than two days a 

 month have fog throughout a 24 hour period. However, in 

 January 1950, a continuous fog was recorded lasting 94 hours, 



