| OCR Text |
Show Water Supply Forecasts for the Western United States are published annually by the U. S. Weather Bureau for the five months, January through May. The bulletins for January and February of the water year 1951-1952 are at hand as this Third Annual Report of the Commission is being prepared. The three later bulletins for this season will be received in due time. The March number will include revised and therefore more accurate forecasts, but probably not in time to include them in this statement. The following is quoted from the February issue, concerning the Colorado Basin. "January brought above-normal precipitation to most of the Upper Colorado River Basin. In general, precipitation amounts ranged from 130% to 180% of normal; over the upper San Juan, from 170% to 300% of normal. The only areas having below-normal precipitation were lower stations in the Duchesne and Grand River Valleys and the extreme headwater area of the Green River in Wyoming. "Colorado River above Cisco: The current water supply outlook for the Colorado and its tributaries above Cameo and for the Taylor River Basin is excellent; even if subsequent precipitation is as low as the minimum of record, runoff equal to or exceeding the 10-ye,ar average should be realized for these areas. The outlook for the Uncompahgre River is much less favorable; precipitation for the balance of the season must approach the maximum of record if average streamflow is to be realized. Median forecasts for the Dolores River Basin are for flows near the 1940-1949 average, which is much in excess of the low flows of the past two water years. "Green River Basin: With the exception of the Wyoming drainage area of the upper Green River, runoff greatly exceeding the 10-year average is expected for the basin if precipitation for the remainder of the season is near normal. The Utah portion of the basin has the most favorable water-supply outlook. Median forecasts for the Utah tributaries range from 155% of the 10-year average for the Ashley Creek near Vernal to 190% of the average for the Strawberry River at Duchesne. The below-normal seasonal precipitation over the upper Green River watershed in Wyoming is reflected by this month's median forecast of 83% of the 10-year average for the Green River near Linwood. "San Juan River Basin: As a result of the heavy precipitation which occurred during the past month, substantial increases are noted in the forecasts for the San Juan Basin. With near-normal precipitation for the balance of the season, 111% to 121% of the 10-year average flow is in prospect for the basin. Above-normal stream- -36- |
