Conflicting reports about Colorado snow pack?

Just last week I posted a link to an article saying the northern Colorado snow pack was slightly above the 30-year average, even though much of the state remains in drought conditions. Saturday, the same news source posted an article saying the state's snow pack is slightly below the 30-year average. 

So, what's the story? 

As of 1 March, the state-wide snow pack was above average for all the major basins. February was, however, quite dry, and lead to decreases in the percent of normal across all basins. [source: US Dept of Agriculture, Nat'l Resources Conservation Service] It is also notable that the dry conditions in early 2009 have made the snowpack much less than in 2008. The story from Friday, supposedly from GreeleyTribune.com (I can not find the article) specifically is about the 1 April report, though. 

Although the report from the USDA NRCS for 1 April does not appear to be available, the data is. Looking at the Basin reports, it is clear that the FortCollinsNow.com article from 1 April is misleading. Here are the relevant numbers:

BENNETT CREEK         83 64
BIG SOUTH             50 79
CAMERON PASS         105 108
CHAMBERS LAKE         74 72
HOURGLASS LAKE        69 64
RED FEATHER           91 94
Basin Totals          93% 95%
Number Courses         9  8
                   (LSWE = 108.5) (SWE = 93.3)
                   (LAST = 117.0) (AVG = 97.7)

Cameron pass is 108% of average, and 105% of last year (these numbers are as of today), just as the article reported. However, Joe Write Resevoir is just 110% of average, not the 112% reported. More importantly though, note that every other station in the Cache La Poudre Basin is below normal, some amazingly below normal. The basin as a whole is at 95% of normal, which is clearly below 100%. 

The Colorado state-wide snowpack stands at 96% of normal as of 1 April. This is the value given in the FortCollinsNow.com article from yesterday.

So to summarize, I think we've learned a couple of things. First, Colorado is, on average, below the 30-year mean snowpack. Second, there is large regional variability, and very large station-to-station variability. Third, we are reminded that news sources are not as reliable as they should be; the numbers in the article I linked to on Friday are a clear cherry-pick. Two spot measurements clearly do not reflect the overall situation in either the Cache La Poudre basin or state-wide. 

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