278 



THE WEATHER 



center of the land division (Fig. 206). This results in prevail- 

 ing southerly winds in summer over most of the United States 

 east of the Rocky Mountains. These winds carry moisture 

 from the Gulf of Mexico and Atlantic Ocean far inland and 

 contribute largely to the ample rainfall of summer over the 

 plains and the Missouri and upper Mississippi valleys. It is 

 this feature of weather control that contributes largely to the 

 fruitfulness of that portion of the country (Fig. 207). 



FIG. 206. Pressure and prevailing winds of the globe for July. 



In winter the land cools much more than neighboring oceans. 

 This develops high pressure over the continents, and this, in 

 turn, causes outflowing winds on all sides (Fig. 208). This 

 results in prevailing west or northwest winds in winter over 

 most of the United States east of the Rockies, with dry, cold 

 weather in the interior, and most of the precipitation confined 

 to the southeastern and eastern sections (Fig. 209). 



304. Land and Sea Breezes. A similar effect, on a much 

 smaller and less important scale, is seen in the sea breeze 

 of afternoon and the land breeze at night, that give comfort 

 and prosperity to scores of summer resorts on many coasts. 



305. Monsoons of India. The Indian monsoons and the 

 remarkable summer rains they carry to the land are a striking 



