568 TWENTY-THIRD ANNUAL YEAR BOOK— PART VIII 



Temperature. The mean temperature for the State, as shown by the rec- 

 ords of 96 stations, was 23.7°, or 3.2° higher than normal. By divisions, 

 three tiers of counties to the division, the means were as follows: North- 

 ern, 18.4°, or 1.3° higher than the normal; Central 24.7°, or 4.0° higher 

 than the normal; Southern, 28.0°, or 4.4° higher than the normal. The 

 highest monthly mean was 31.3°, at Burlington, and the lowest 14.8°, at 

 Rock Rapids The highest temperature reported was 70°, at Clarinda and 

 Mt. Ayr, on the 21st, and the lowest was -20°, at Inwood, on the 13th. The 

 temperature range for the State was 90°. 



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

 79 per cent, and at 7 p. m. it was 66 per cent. The mean for the month 

 was 72 per cent, or 8 per cent lower than the normal. The highest monthly 

 mean was 85 per cent, at Charles City, and the lowest was 66 per cent, at 

 Keokuk. 



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

 records of 97 stations, was 1.59 inches, or 0.44 inch greater than the nor- 

 mal. By divisions the averages were as follows: Northern, 1.96 inches, or 

 1.05 inches more than the normal; Central, 1.43 inches, or 0.23 inch more 

 than the normal; Southern, 1.39 inches, or 0.04 inch more than the normal. 

 The greatest amount, 4.56 inches, occurred at Fayette, and the least. 

 0.40 inch at Spencer. The greatest amount in any 24 hours, 3.20 inches, 

 occurred at Fayette, on the 21st-22d. 



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

 The highest velocity reported from a regular Weather Bureau Station was 

 55 miles per hour, from the west, at Sioux City, on the 1st. 



Snowfall. The average snowfall for the State was 1.3 inches, or 6.1 

 inches less than normal. The greatest amount, 7.4 inches, occurred at 

 Rock Rapids, and there were 21 stations that reported only traces, and 10 

 stations no snow whatever. The snowfall for the State was the least 

 ever recorded, being just half of the least amount previously recorded, 

 which was in 1902. 



Rivers. Low and nearly stationary stages prevailed on the Mississippi 

 and interior rivers until after the general storm of the 21st-22nd, when a 

 sharp rise occurred in the Mississippi and a high stage continued through 

 the rest of the month. Ice gorges caused local floods on many interior 

 rivers and bridges were threatened by ice jams which had to be dyna- 

 mited. In the northeast portion of the State high water and ice caused 

 great damage. Low and nearly stationary stages prevailed on the M:ss- 

 ouri the entire month. 



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

 of sunshine was 65, or 9 per cent more than the normal. The per cent of 

 the possible amount at the regular Weather Bureau Stations was as fol- 

 lows: Charles City, 46; Davenport, 63; Des Moines, 73; Dubuque, 64: 

 Keokuk, 68; Sioux City, 67; Omaha, Nebr., 73. 



Miscellaneous Phenomena. Aurora: 12th, 14th.. Birds (migration of ) : 

 Columbus Junction, robins, 16th; Earlham, blue birds, 21st, black birds, 

 22d. Fog: 1st, 9th, 19th, 21st, 22d. Hail: 1st, 21st, 22d, 23d. Halos (lunar 

 and solar) : 4th, 6th, 7th, 8th, 9th, 10th, 11th, 12th, 13th, 17th, 22d, 23d, 26th 

 27th, 28th. Meteor: 12th. Sleet: 1st, 4th, 5th, 18th, 21st, 22d, 23d, 26th, 

 27th. Thunderstorm: 19th, 21st, 22d. 



