TWENTIETH ANNUAL YEAR BOOK— PART VIII 689 



Humidity. The average relative humidity ior the State at 7 a. m. was 

 83 per cent, and at 7 p. m. it was 68 per cent. The mean for the month 

 was 76 per cent, or about 2 per cent higher than the normal. The highest 

 monthly mean was 80 per cent, at Charles City, and the lowest was 71 at 

 Keokuk. 



Precipitation. The average precipitation for the State, as shown by the 

 records of 109 stations, was 2.33 inches, or 0.56 inch more than the normal. 

 By divisions the averages were as follows: Northern, 1.58 inches, or 0.05 

 inch more than the normal; Central, 2.44 inches, or 0.57 inch more than 

 the normal; Southern, 2.98 inches, or 1.06 inches more than the normal. 

 The greatest amount, 5.40 inches, occurred at Lacona, and the least. 0.81 

 inch at Spencer. The greatest amount in any 24 consecutive hours, 3.50 

 inches, occurred at Muscatine on the 16th. 



Snow. The average snowfall for the State was 1.1 inches, or 4.2 inches 

 less than the normal. The greatest amount, 5.5 inches occurred at Rock 

 Rapids. Fourteen stations reported no snow, and 20 stations reported only 

 a trace. 



Wind. The prevailing direction of the wind was from the southeast. 

 The highest velocity reported from a regular Weather Bureau station was 

 at the rate of 45 miles an hour from the southeast, this occurring at Sioux 

 City on the 14th. 



Simshine and Cloudiness. The average per cent of the possible amount 

 of sunshine was 60, or about 2 per cent higher than the normal. The per 

 cent of the possible amount at the regular Weather Bureau stations was 

 as follows: Charles City, 51; Davenport, 54; Des Moines, 62; Dubuque, 

 63; Keokuk, 67; Sioux City, 60; Omaha, Neb., 62. 



Rivers. Stages above normal prevailed in most of the interior rivers 

 of the State during the winter, which was so mild that in the central and 

 southern portions the rivers remained open much of the time and there wa.s 

 no well-defined spring breakup. Heavy rains, March 14-16, caused marked 

 rises in all of the rivers. The smaller streams of the eastern parts of the 

 State overflowed and caused some damage by washouts and interfering 

 with railway traffic. Three persons were drowned near Waukon, Allamakee 

 County, while crossing what had been a dry run before the storm. The 

 Des Moines River at Des Moines reached a crest stage of 8.4 feet, 8.6 feet 

 below flood stage, on the 19tli, but about 50 miles down stream where the 

 drainage area received heavier rains the flood stage was reached. At Ot- 

 tumwa it rose 8.8 feet to a crest stage of 13.2 feet, 3.2 feet above flood 

 stage, on the 18th. Moderate crests passed down the boundary rivers be- 

 tween the 19th and 24th. 



Miscellaneous Phenomena. Aurora, 1st, 5th, 8th, 12th, 19th, 20th, 21st, 

 27th, 28th, 31st. Birds: (migration of) Corydon, robins and bluebirds on 

 the 10th; Earlhanj, bluebirds on the 9th, robins and meadow larks on the 

 13th, wild geese and ducks on the 13th; Murray, robins and bluebirds on the 

 8th; Boone, robins on the 11th, bluebirds on the 12th; Whitten, robins on 

 the 10th; Nora Springs, robins and meadow larks on the 23d; Pocahontas, 

 robins, meadow larks and wild ducks on the 13th and 14th; Postville, blue- 

 birds on the 12th, robins on the 15th, blackbirds, on the 16th; Sanborn, 



44 



