IOWA WEATHER AND CROP REPORT 591 



State as a whole, more than half of the monthly total occurred during a 

 single 24-hour period. While the precipitation was generally deficient, 

 there was sufficient to keep pastures in good condition and benefited 

 truck crops, but the lack of rain over the northern and western portions 

 of the State caused a suspension of plowing, prevented the germination oi 

 winter wheat and caused a shortage of stock water. The weather was un- 

 usually favorable for the maturing of the corn crop and at the end of the 

 month not more than 6 per cent was susceptible to injury from frost. 

 Low humidity, hot weather and an excess of sunshine caused some corn 

 to mature too rapidly so it became loose on the cob and lessened the yield 

 somewhat. The dry weather retarded the seeding of winter wheat some* 

 what, but much seeding was intentionally delayed to avoid the Hessian 

 fly pest. 



No severe storms of any character occurred during the month. The only 

 damage reported was from a local wind squall in the northern portion of 

 Cerro Gordo County that blew down a number of telephone poles, frail 

 buildings and trees. Roads were in good condition except somewhat rough 

 after the rainy periods and all outside work was carried on with very little 

 interruption. 



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

 30.07 inches. The highest recorded was 30.54 inches, at Dubuque, on the 

 16th, and the lowest was 29.62 inches, at Des Moines, on the 1st, and Sioux 

 City, on the 5th. The monthly range was 0.92 inch. 



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

 records of 100 stations, was 67.1°, or 3.7° higher than the normal. By 

 divisions, three tiers of counties to the division, the means were as fob 

 lows: Northern, 66 0°, or 4.2° higher than the normal; Central 67.3°, or 

 3.8° higher than the normal; Southern, 68.1°, or 3.1° higher than the nor- 

 mal. The highest monthly mean was 70.4°, at Fairport, and the lowest 

 was 63.0°, at Postville. The highest temperature reported was 103°, at 

 Belle Plaine and Mason City, on the 6th, and the lowest was 31°, at 

 Washta, on the 11th. The monthly range for the State was 72°. 



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

 records of 103 stations, was 2.03 inches, or 1.33 inches less than the nor- 

 mal. By divisions, the averages were as follows: Northern, 1.69 inches, 

 or 1.36 inches less than the normal; Central, 2.24 inches, or 1.22 inches 

 less than the normal; Southern, 2.17 inches, or 1.39 inches less than tho 

 normal. The greatest amount, 4 34 inches, occurred at Iowa Falls, and 

 the least, 0.31 inch, occurred at Inwood and Milford. The greatest amount 

 in 24 consecutive hours, 3.05 inches, occurred at Le Mars, on the 18th. 



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

 81 per cent, and at 7 p. m. was 60 per cent. The mean for the month was 

 70 per cent, or 4 per cent below the normal. The highest monthly mean 

 was 77 per cent at Charles City, and the lowest was 62 per cent, at Sioux 

 City. 



Sunshine. The average per cent of the possible amount of sunshine 

 was 71, which is 9 per cent above the normal. The per cent of the possible 

 amount at the regular Weather Bureau stations was as follows: Charles 



