BASIN Home
BASIN Text Image
Current Theme: Waterworks
Snowpack report - Niwot Ridge - February, 2003
Mark Losleben - CU INSTAAR Research Staff

The following snowpack conditions on Niwot Ridge have been reported by Mark Losleben for February, 2003. Select here for more information about these snowpack reports

Finally, a snowy February blessed us, after a (too) long dry spell, this year! At C1, Niwot Ridge, we recieved 44.9 inches of snowfall, and 3.17" SWE (snow water equivalent), and have a snowpack 38.5" deep with a SWE content of 8.5", as of 27 February 2003 (manual measurements). The SWE content is 81% of average, which is a hefty increase over a month ago when it was a mere 60%, showing nearly a 1%/day increase!

Note that February is a much easier month to catch up than March, on a percentage basis, because it is normally much drier than March. (In other words, an additional inch of SWE has a much greater impact on the average in February than it does in March).

According to the SnoTel network, the Niwot snowpack agrees well with the manual measurement, 81% of average. The cummulative winter precipitation to date is 94%, meaning we are still behind in what we might nomrally expect in the snowpack given how much precipitation has fallen this winter. This is also true for the South Platte basin as a whole (81% SWE and 89% precipitation), but is not true for many of the basins in the state, for a change.

The Yampa/White and Upper Colorado basins have the top snowpack SWE percentages, 90%, but the Yampa/White has recieved 92% of their average precipitation this season, and the Upper Colorado a little less, 88%, as of 27 February. The San Miguel/Dolores/Animas/San Juan area has the least snowpack, at 72% (79% precipitation), and the Upper Rio Grande is close, with 73% SWE and 78% precipitation. Both of these are a great improvement over last month when they were 64% and 58%, respectively.

So, the southwest corner of the state contiues to be the driest area, and the nothern areas wettest, but all parts have increased their snowpack compared to average, in February. Many folks are predicting an above average snowfall in March, so the future is looking more promising than it has any time last year.

For a little broader perspective, snowpack SWE conditions over the full western US show a mixed El Nino pattern. Consistent with this pattern, the northwest Pacific regions are dry (the Coast Range of Oregon has 0% of its snowpack right now), but the southwestern regions which should be wet, are also drier than normal (Arizona snowpacks range between 35 and 70%). Colorado actually has one of the healtier snowpacks compared to the other western states. Some SWE ranges for other states:

Northern NM is actually doing quite well, with four basins over 100%, but the southern part of the state is dry (Gila basin has 55%).

Alaska is interesting because its snowpack is a low 35-72% but its winter precipitation is 105-138%, a very clear indication that warmth (and other factors) are hindering snowack formation there.

In summary, February was a good month for Colorado, and the March outlook is favorable for a continued recovery. The manual historical snowpack record follows.


                      Snow Water Content (inches)
                      Values are for the end of given month
                      except as noted for May and June


     Season     Dec      Jan      Feb      Mar      Apr     May          
      81/82    4.75     10.5     11.75    15.5     14.9    12.0   (17th)
      82/83    3.63              4.75     12.75     17     11.75  (30th)
      83/84    12.6     13.25     15      18.9     20.75
      84/85    3.75     6.25      8.5     10.25    8.75
      85/86     6.5      7.5      14      15.38    17.5
      86/87    6.25     8.75     11.25    12.75    11.75
      87/88     6.5      9.1     12.4     15.75    14.5
      88/89     5.5      7.6      11      10.25     5.6
      89/90     6.5     9.25     10.75    16.1     16.5
      90/91      3        5       7.1     9.38      10
      91/92    6.65     6.75      8.5     12.25    10.25
      92/93    5.75     6.75     10.75     14      15.875
      93/94    7.125    9.063    12.25    13.25    13.25     2.5  (18th)
      94/95    2.625    3.925     7.0     10.125   16.75    17.0  (22nd)  
                                                            19.75 (30th)
      95/96    7.50     12.00    17.5     20.375   18.75     6.125 (15th)
      96/97    8.75     12.625   15.125   14.625   20.375   18.0   (15th)
      97/98    7.0625   10.0     10.125   12.875   17.25    12.875 (15th)
      98/99    3.25     6.625     8.375    9.125   14.125   14.25  (15th)
      99/2000  3.5      7.5      10.625   12.375    7.625
      00/2001  4.375    5.375     7.125   10.00     9.125
      01/2002  2.625    4.25      6.19     7.563    0.0
      02/2003  4.00     5.25      8.5

     Average   5.554    7.967    10.389   13.027    13.363

Addendum

Please pardon the major omission in yesterdays C1 snowpack report. I did not give last years figures for comparison, so here they are:


       Feb 2002                  Feb 2003

Niwot (manual)       58%      81%
      (SnoTel)       53%      81%

S. Platte basin      57%      81%

State Maximum        68%      90%   Upper Colorado basin both years
State Minimum        42%      72%   San Miguel/Animas/Dolores/San Juan both years

Contact Mark Losleben with comments or questions
Snowpack report for January, 2003
Snowpack report for March, 2003
General information about Niwot Ridge (C1) Snowpack reports

INVITATION BASIN is a community project actively seeking public participation. We appreciate all feedback and welcome comments, suggestions and contributions. To find out more about how you can be involved, click here.

BASIN is supported by the US EPA, the City of Boulder, WASH, BCWI and BCN
Home | Site Map | Glossary | Bibliography | Contributors
About BASIN | Attribution | Feedback | Search
Last Page Update - Sunday January 15, 2006