By May 1, the snowpack as a percent of average had increased in most areas, and forecasts were raised slightly. Although, the snowpack had increased to near normal in the upper Colorado and above normal in the Gunnison and Dolores, the variability was high. For example, on May 1, in the Blue River basin, Grizzly Peak SNOTEL was 94% of average but Summit Ranch SNOTEL was 131% of average. In the upper Gunnison, Butte SNOTEL was 93% of average, yet Porphyry Creek SNOTEL was 134% of average. On April 30, in the Dolores River basin, Scotch Creek SNOTEL was 37% of average and El Diente Peak SNOTEL was 138% of average.
The three graphs shown below depict the 50% probability forecast and the associated reasonable maximum and minimum for three streamflow points. These forecasts are fairly indicative of the range of forecasting for water year 1998. That is, some points were overforecasted and others underforecasted. The mixed forecasts reflect the difficulty in quantifying areal conditions using point data that show significant variations in conditions within and among neighboring basins.