CLIMATE 
71 
River Valley, nearly all of Ohio, the northern half of Illinois, 
western Kansas, or the Columbia River Valley. 
The Southern Highlands includes the rough and rolling region, 
generally over 1,000 feet in elevation, extending from Clark 
County south to the Illinois line, and lying between the Missis¬ 
sippi Valley on the west and the Wisconsin and Rock River 
Valleys on the east. It is characterized by a cooler temperature 
than the adjoining valleys, the summer temperature (66° to 29° 
E.) being similar to that along the Michigan shore, while the 
mean winter temperature is only 2° higher than along the 
Superior shore. The growing season, averaging 145 days, is 
apparently 20 to 30 days shorter than on the lower lands of the 
State in the same latitude, while in the river valleys and ravines 
in this section the frost danger is still greater. 
The first of the following tables gives the mean monthly and 
annual temperature and precipitation at Wabasha, Minn., and 
at Whitehall, Wis. Wabasha is situated just across the Missis¬ 
sippi River from Buffalo County, and Whitehall is located in 
Trempealeau County, which borders Buffalo County on the east. 
The station at Wabasha has an elevation of 681 feet above sea 
level and the station at Whitehall is 675 feet above sea level, so 
that these records indicate the weather conditions of the Missis¬ 
sippi Valley and the Trempealeau River Valley rather than of 
the whole region surveyed. The greater part of the county is 
from 200 to 400 feet higher than the river valleys, and varies 
somewhat in the length of growing season, as indicated above. 
The second table gives the normal monthly, seasonal, and 
annual temperature and precipitation and the average dates of 
first and last killing frosts at Eau Claire, about 14 miles north 
of the north county line. This station has an elevation of 800 
feet. A comparison with the tables from the other points men¬ 
tioned may be of interest. 
