Snow melting forecast fading for state

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With about half of the snow accumulation season for the northern New Mexico mountains concluded, and a weak to moderate La Niña expected to persist through early 2012, the prospects for a better than normal spring snow melt runoff season are fading for northern New Mexico.
The erratic and highly variable winter storm track, as well as the potential for a drier than normal La Niña-influenced spring, do not bode well for water supply forecasts in several key northern New Mexico river basins.
Forecast flows for the Rio Grande include 79 percent of normal into Cochiti Lake and 70 percent at Elephant Butte Lake.
Other reservoir forecast inflows include 74 percent of normal at El Vado Lake and 89 percent of normal for Santa Rosa Lake.
Navajo Reservoir is expecting 80 percent of normal inflow. Inflow to Conchas Lake is forecast to be 65 percent of the 30 year March through June median inflow.
Precipitation amounts across New Mexico during January 2012 ranged from zero in the east central plains to near normal at a few spots in the mid Rio Grande Valley.
Most areas of the state and nearly all mountain regions saw well below normal precipitation during January. Seasonal precipitation, October 2011 through January 2012, was below normal in parts of the southeast corner of the state but near normal to above normal elsewhere in New Mexico.
Surveys by the U.S. Department of Agriculture’s Natural Resources Conservation Service indicate that snowpack water content in the Rio Grande Basin as of February 1 was 85 percent of normal and 124 percent of one year ago.
In the San Juan Basin the snowpack water content was 71 percent of normal and 67 percent of the total of Feb. 1.
The Rio Grande Basin snowpack water content average of 85 percent of normal as of Feb. 1 was a combination of near normal snowpack in the Sangre de Cristo Mountains and below normal snowpack in the Rio Chama Basin and Jemez River Basin.
Snowpack water content on the high peaks and east slopes of the Sangre de Cristo Mountains that comprise the headwaters of the Pecos River Basin and Cimarron River Basin ranged from near normal to 120 percent of normal respectively.
The water supply forecast issued in early February 2011 also followed a much drier than normal January and also anticipated a drier than normal spring due to the influences of an ongoing La Niña event.
An abysmally dry spring for all but the far northwest corner of the state in 2011 resulted in a poor snow melt runoff season even as La Niña weakened.  
Odds are against the spring of 2012 as being as dry as 2011, but still favor spring 2012 as being drier than normal.
New Mexico reservoir storage is well below normal in the Rio Grande Basin, Canadian Basin, and Pecos Basin, but near normal at Navajo Lake. In the Rio Grande basin, storage is 46 percent of the 1971 to 2000 normal and 83 percent of last years storage at this time.
In the San Juan basin, Navajo Reservoir storage is 104 percent of the 30 year normal, and 97 percent of the storage of one year ago.
This water supply forecast reflects conditions as of Feb. 1 and assumes near normal to below normal precipitation through rest of this winter and into the spring.