WSP08299 - Laserfiche WebLink

Home Browse Search

4$01 . . 17. CLIMATOLOGY.- Wide variations of climate occur in the Arkansas Basin above Pueblo darnsite. In the mountainous regions of the headwaters precipitation varies widely over relatively short distances. It varies from 10 inches annually in some locations to 40 inches annually over limited areas. Much of the total precipitation at the higher elevations' is in the form of snow. Runoff from snowmelt constitutes a dependable water supply for municipal, irrigation, industrial, and other uses. In the plains region most of the precipitation is in the form of rainfall. At times, occurrences in the form of violent cloudbursts cause flash floods of short durations and small volumes but of damaging intensities. More than 80 percent of the average annual precipitation on the plains occurs during the period April through October, " 18. Annual precipitation normals within the watershed vary from 24.27 inches at Lake Moraine to 9.69 inches at Buena Vista. During the six-month period, April through September, Lake ~loraine gets 76 per- cent of the annual normal, and Buena Vista gets 68 percent. The maximum rainfall months are Nay and July throughout most of the basin. Thunder- storm activity is greatest in July with an average of 13 days at Pueblo. A maximu," 24-hour, or maximum observed day precipitation of 6.10 inches occurred at Rye, Co 1 0" in ~lay 1955. The June 1965 storm produced a maximum 24-hour precipitation amount of 11,08 inches at Holly, Colo. 19. ~Iean annual sno\<fall amounts vary from 146 inches at Lake Moraine to 33 inches at Canon City. Pueblo Weather Bureau Airport has had a maximum month ly sno\<fall of 29.3 inches, and a maximum 24-hour amount of 16.8 inches. ~fonth ly and annual precipitation normal s for representative weather stations in and adjoining the Arkansas \<ater- shed above John clartin Darn are tabulated in table 1. Locations of weather stations are shown on plate 2. 20. There is a wide variation of temperatures in the Arkansas Basin above the Pueblo damsite. This is due principally to the varia- ~ - - - - -, -tion--in-altituae-;-Leaavi11e;- aCelevatTonro-;-r77-feet, nas-a mean annual - - -- maximum and minimum of 50.7 and 21.9 degrees, respectively; whereas Pueblo at elevation 4,700 feet has a mean annual maximum and minimum,of 68.0 and 37.3 degrees, respectively. Extreme temperatures have ranged from 105 degrees at Pueblo to a -54 degree" at Westcliffe, elevation 7,860 feet. The average last spring occurrence of 32 degrees varies from 28 April at Pueblo Weather Bureau Airport to 24 June at Lake ~Ioraine. TIle average first fall occurrence of frost at the same locations are 12 October and 23 August. j 21. Relative humidity records are available for only one station in the vicinity of the Pueblo project. The Pueblo Weather Bureau Air- port record shows average relative humidities at 5:00 a.m., 11:00 a.m., 5:00 p,m., and 11:00 p.m. to be 65, 38, 41, and 61 percent, respectively. 6