THIRTEENTH ANNUAL YEAR BOOK— PART I 7 



Driest February, 1904, with total precipitation of 0.41 inch. 



Average depth of snowfall, 7.3 inches, (1892 to 1912 inclusive). 



Greatest snowfall in February, 15.5 inches in 1905. 



Least snowfall in February, 2.6 inches in 1902. 



Average number of days with 0.01 inch or more of precipitation, 5. 



Prevailing wind direction, northwest. 



Average number of clear days, 12; partly cloudy, 8; cloudy, 8. 



THE WINTER OF 1911-1912. 



The mean temperature for the three winter months is 16.7°, which 

 is 5.9° below the normal for the state. The highest temperature reported 

 was 60°, at Keokuk, Lee County, on December 10th. The lowest tempera- 

 ture reported was — 47°, at Washta, Cherokee County, on January 12th. 

 The average monthly precipitation for the state was 1.44 inches, and the 

 average total precipitation was 4.31 inches, or 0.91 inch above the winter 

 normal. The average total snowfall, unmelted, was 29.3 inches, or 12.0 

 inches more than for the winter of 1910-1911. The average number of 

 days with .01 inch or more of precipitation was 17, or 3 more than for 

 the previous winter. The average number of clear days was 37, partly 

 cloudy, 22; cloudy, 32, as compared with 36 clear, 21 partly cloudy, and 

 33 cloudy days during the winter of 1910-1911. The winters of 1892-3; 

 1903-4; and 1904-5 were colder than the past winter. The average tem- 

 peratures for those winters were 14.9°, 16.1°, and 15.8° respectively, but 

 January, 1912, was much colder than any month on record. 



MARCH. 



With the exception of March, 1899, the month was the coldest March 

 of which we have a record in this state. The average temperature of 

 the past month for 113 stations is 24.9°, and while the mean of the rec- 

 ords of 125 stations for March, 1899, was 23°, the average tempera- 

 ture of the regular weather bureau stations at Charles City, Davenport, 

 Des Moines, Dubuque, Keokuk, Omaha, and Sioux City, where the ther- 

 mometers and their location have remained practically the same, is 

 0.4° lower for the past month than it was for March, 1899. The records at 

 Dubuque, which are complete for 60 years, except for 1857, 1872 and 1873, 

 show the month just closed to have been 0.6° colder than any other 

 March in the history of the station. The first half of the month was 

 remarkable for the persistency of low temperatures, the means being 

 from 10° to 25° below the normal almost daily. The latter half of the 

 month was milder, but on only one or two days was the mean temperature 

 above the normal or the minimum temperature above the freezing 

 point. However, a decided change to spring-like conditions set in toward 

 the close of the month, during which time the snow melted rapidly and 

 by the 31st it had practically disappeared, except where it lay in drifts. 

 Some frost remained in the ground at the close of the month, but the 

 amount was inconsiderable. Nearly all of the precipitation was in the 

 form of snow, and while there were four principal storm periods, the 

 storms of the 14th-15th and 20th were the only ones of importance. That 



