Milk River Basin - Water Supply Forecasts

As of April 1, 2007, below average to average natural runoff volumes are forecast for the March to September 2007 period in the Milk River basin (Table 3a). Current forecasts in the basin range from 80 to 94% of the median, 18 to 25% higher than volumes recorded during the March through September 2006 period. For the Milk River at Milk River, current forecasted values for the March to September 2007 period would rank 37th lowest in 91 years of record (1912-2001).

Forecasts are similar to those published on March 1 for Western Crossing, and lower for Milk River and Eastern Crossing. Precipitation during March was much below normal in most areas, but near normal at higher elevations.

The first month of the forecast period has been completed, with March 2007 recorded natural runoff volumes ranging from 222% of average at Western Crossing to 105% at Eastern Crossing. Recorded volume data is preliminary, due to ice effects, and is subject to change. Early melting of snowpack in this low elevation basin, in combination with near normal precipitation during March in the upper basin, are the reasons for the high March runoff. March volumes typically comprise a small portion of the March to September total. The remaining volume forecast, which is the March to September 2007 forecast minus the recorded volume to date, is available in Table 3b. The forecast is for below average to average April to September 2007 natural runoff volumes.