EIGHTEENTH ANNUAL YEAR BOOK— PART IX 487 



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

 30.03 inches. The highest recorded was 30.59 inches, at Sioux City, on 

 the 23d, and the lowest was 29.32 inches, at Davenport, on the 26th. 

 The monthly range was 1.27 inches. 



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

 records of 102 stations, was 42.9°, or 7.9° below the normal. By divisions, 

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

 ern, 40.8', of 8.2° below the normal; Central, 42.9°, or 8.0° below the nor- 

 mal; Southern, 45.1° ,or 7.5° below the normal. The highest monthly mean 

 was 47.8°, at Northboro, and the lowest 38.1°, at Northwood. The highest 

 temperature reported was 85°, at Mason City, on the 2d; the lowest was 

 0°, at Galva, on the 30th. The range for the State was 85°. 



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

 records of 108 stations, was 1.41 inches, or 1.05 inches less than the nor- 

 mal. By divisions the averages were as follows: Northern, 1.31 inches, 

 or 1.03 inches less than the normal; Central, 1.49 inches, or 1.00 inch less 

 than the normal; Southern, 1.44 inches, or 1.10 inches less than the 

 normal. The greatest amount, 4.00 inches, occurred at Davenport, and 

 the least, 0.15 inch, at Rock Rapids. The greatest amount in 24 con- 

 secutive hours, 2.02 inches, occurred at Davenport on the 16th-17th. 



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

 75 per cent, and at 7 p. m., 55 per cent. The mean for the month was 65 

 per cent, or 6 per cent below the normal. The highest monthly mean was 

 77 per cent, at Charles City, and the lowest, 54 per cent, at Omaha, Nebr. 



Snoto.— The first light snow flurries of the season occurred in nearly 

 all portions of the State on the 11th. Other snows covered portions of 

 the State on the 22d-23d and 26th-27th, but the first large, general snow 

 storm occurred on the 2Sth-29th, when the amount varied from 11.0 inches 

 at Decorah in the northeast to none at Rock Rapids in the extreme north- 

 west and Thurman in the southwest. At Decorah this snowfall is said to 

 be the greatest in October for more than 40 years. 



The average fall for the month for the whole State is 2.2 inches which 

 has been exceeded but twice since 1892. The greatest monthly amount is 

 12.5 inches at Decorah. 



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

 The highest velocity reported from a regular Weather Bureau station 

 was 57 miles an hour from the northwest, at Sioux City, on the 22d. 



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

 of sunshine was 44, or 17 per cent below the normal. The per cent of 

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

 lows: Charles City, 19; Davenport, 41; Des Moines, 51; Dubuque, 38; 

 Keokuk, 45; Sioux City, 54; Omaha, Nebr., 59. 



Miscellaneous Phenomena. — Fog: 1st, 3d, 6th, 11th, 17th, 18th, 19th, 

 24th, 25th, 28th, 29th. 



Frost: 1st, 6th, Sth (not recorded after first killing). 



Hail: 9th, 10th, 11th, 17th, ISth, 20th. 



Halos (lunar or solar). 2d, 3d, 4th, 7th, 8th, 19th, 24th, 26th, 30th. 



Sleet: 9th, 11th, 28th, 29th. 



Thunderstorms: 2d, 9th, 16th, 17th, 18th, 25th. 



Rivers. — The rivers remained nearly stationary during the month. 



