Wednesday, January 23, 2013

Salmon River watershed snow & streamflow report

The US Natural Resources Conservation Service (NRCS) is THE most authoritative source for the status of the snowpack as well as what type of runoff we might expect when the snow melts.

We downloaded their report and then uploaded it to a PDF viewer.  You can actually easily read the document online without downloading it if you choose.  The full report in the online reader appears below narrative for The Salmon River.

Here is what the NRCS has to say about the current status of Salmon River snow and streamflow:


"The water year is off to a good start in the Salmon Basin. Monthly precipitation in October, November and December was above average, leaving water year to date precipitation at 128% of average since October 1. The season’s first storms produced rain at SNOTELs below 6,500 feet, meanwhile snow piled up at higher elevation stations. The Salmon’s snowpack still displays quite a disparity above and below this threshold elevation. As of January 1 snow at sites above 6,500 feet is 123% of normal, while snow at sites below 6,500 feet is 80% of normal. Overall the Salmon basin snowpack is 113% of normal. 

Streamflow forecasts show the potential for excellent summer flows. The MF Salmon River is forecast at 130% of normal while the Salmon River at Salmon is forecast at 121%. The influence of changing averages, as mentioned on this month’s cover, is slightly reduced in the Salmon basin as compared to other parts of Idaho. Overall the Salmon basin snowpack is about 8 percentages points higher using the 1981-2010 normal, instead of the 1971-2000 average. Nonetheless, please understand the effects of the average change and recalibrate your expectations, so the somewhat inflated snow and streamflow percentages don’t let you down when the snow starts melting."

SOURCE: ftp://ftp-fc.sc.egov.usda.gov/ID/snow/watersupply/bor/2013/borid113.pdf


No comments: