EIGHTEENTH ANNUAL YEAR BOOK— PART IX 471 



APRIL. 



April, 1917, was generally cold, cloudy and rainy. Only a few days, 

 particularly the 18th and 22d, were notably warm. The week, 9th-15th, 

 was the least rainy, after which rain fell somewhere in the State every 

 day, being heavy the last four days. Rainy days, averaging 11, nearly 

 equaled the record of April, 1909, which had 12. Snowfall, 3.8 inches, has 

 not been exceeded in April since 1896. It was heaviest in the southern 

 division, where it averaged 5.4 inches which is greater than the total 

 of the preceding three months. In Wayne and Decatur counties it ex- 

 ceeded one foot. The drought of several months in the central and 

 southern divisions was effectually broken. Cloudy days, 14, is the great- 

 est of record for April; and sunshine was correspondingly deficient. 



Vegetation made slow progress. Winter wheat and meadows had win- 

 ter-killed so badly that a large acreage was plowed up and devoted to 

 other crops, mainly corn, though there was also a large increase in the 

 acreage of oats and potatoes. Where the stand was considered promis- 

 ing enough to allow the winter wheat to grow, and this was mostly on 

 heavy bottom lands, it made fair progress, as did other small grains, the 

 seeding of which was about completed by the third week. Wet weather 

 delayed the preparation of corn ground so that at the close of the month 

 only a little planting had been done in the southern counties. Pastures 

 and meadows were too backward to turn in stock. The pig crop was re- 

 ported as below normal. Trees and fruits were generally dormant. 



Pressure. — The mean pressure, (reduced to sea level) for the State 

 was 29.99 inches. The highest recorded was 30.36 inches, at Sioux City, 

 on the 8th, and the lowest was 29.51 inches at Omaha, Neb., on the 20th. 

 The monthly range was 0'.85 inch. 



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

 records of 107 stations, was 45.5°, or 3.2° lower than the normal. By 

 ■ divisions, three tiers of counties to the division, the means were as fol- 

 lows: Northern, 43.8°, or 2.9° lower than the normal; Central, 45.9°, or 

 3.0° lower than the normal; Southern, 46.8° or 3.8° lower than the normal. 

 The highest monthly mean was 49.4°, at Mt. Pleasant and Tipton, and 

 the lowest was 41.8°, at Sibley. The highest temperature reported was 

 8'8°, at Lenox, on the 19th, and the lowest was 17° at Guthrie Center on 

 the 2d, and at Sibley on the 15th. The temperature range for the State 

 was 71°. 



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

 78 per cent, and at 7 p. m. it was 63 per cent. The mean for the month 

 was 70 per cent, or about 3 per cent above the normal. The highest 

 monthly mean was 74 per cent, at Charles City and Sioux City, and the 

 lowest was 64 per cent, at Dubuque. 



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

 the records of 117 stations, was 4.55 inches, or 1.69 inches more than 

 the normal. By divisions the averages were as follows: Northern, 3.93 

 inches, or 1.25 inches more than the normal; Central, 4.44 inches, or 1.5S 

 inches more than the normal; Southern, 5.27 inches, or 2.22 inches more 



