Center for Snow and Avalanche Studies

Swamp Angel Study Site
Swamp Angel Study Plot (subalpine)

Senator Beck Study Site
Senator Beck Study Plot (alpine)

Putney Study Site
Putney Study Plot (summit)

Senator Beck Basin Stream Gauge
Basin Stream Gauge

St Paul Basestation
St. Paul RF Base Station

The Center for Snow & Avalanche Studies serves the mountain science community and regional resource managers by hosting & conducting interdisciplinary research and conducting integrative 24/7/365 monitoring that captures weather, snowpack, radiation, soils, plant community and hydrologic signals of regional climate trends.

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Mountain System Monitoring: Winter Storm Data


  Past Winter Storm Reports:

This CSAS Storm and Precip Data xlsx file contains the current and past 11 seasons of CSAS winter storm data, including:

  • Dates, times and duration of each winter storm event
    (2003-current)
  • Change in the height of snow at both our alpine Senator Beck study plot and our subalpine Swamp Angel site.
  • Peak gust data from our Putney site.
  • Mean and maximum precipitation intensity during each storm
  • Total new water accumulation in mm for each storm event.
  • Summary data for each month of the season.
  • Cummulative annual precipitation graph by month

See our Current Conditions for the latest hourly data. All times shown are in Mountain Standard Time (MST)


2014-2015 Winter Storm Reports:

Winter Storm #4: December 13-14, 2014
Greetings from Silverton on Monday morning, December 15 - It's a clear, 'crisp', San Juan morning, at -6 F here in town, with bright sun on the peaks above.

Aside from receiving 11 mm of precip on December 3rd (just 1 mm short of our threshold for a Winter Storm), our dry-ish December ended last weekend with a slightly over-achieving Storm #4 producing a 37 cm (14.6") gain in snowpack depth and a 32 mm (1.26") gain in snowcover water content.  The Storm #4 Report is attached.

We'll hope that the Pacific keeps sending systems our way.  California may have a love/hate relationship with these major "atmospheric river" precipitation events, aka "Pineapple Express" storms, but Colorado probably can't get enough of them, even if we're just getting the dregs. Storm Report #4 (pdf).

Winter Storm #3: November 22-25, 2014
Greetings from Silverton - It's a very mild (28 F) Wednesday morning, November 26, a nice reprieve from a string of cold mornings.

Here is the Storm Report for our third winter storm of winter 2014/2015. This storm began with some intensity for the first 24 hours but then tapered to a long-duration, lower intensity event. One long interval of 10 hours without a recorded mm of precip almost ended the storm at 2000 hrs on Monday (using our 12-hour break in precip rule for 'storm end'). That would have shortened the storm length by a full day but another 4 mm fell on Monday and stretched the storm to 2000 hrs Tuesday, for a full 72 hours in duration.

Storm #3 was a significant precip event with quite sustained NW-N winds. Wind redistribution of the 1.8" of water equivalent resulted in substantial loading to leeward slopes (and cross-loading of terrain on some windward slopes). And, winds continue this morning, still from the NW. But, given the sustained storm period winds, there may not be much loose snow left in the fetches to move.

This Storm #3 has brought our Water Year (Water Years start October 1) total precip to 197 mm, a little shy of the 210 mm we had received in October and November 2013, last winter, after a total of five winter storms. Our 11 year period of record at Swamp Angel Study Plot has averaged 1.8 numbered winter storms in October and another 3.1 storms in November, with an average total of 191.5 mm of precip collected by the end of November. So, we're a little short on numbered storms so far this year, but a little above that average end-of-November total precip. Storm Report #3 (pdf).

Winter Storm #2: November 14-15, 2014
Greetings from Silverton - Sunday morning dawned clear and cold (5 F in Silverton, -4 F at Putney) here in the western San Juans following a long winter storm - our Storm #2 of the winter of 2014/2015. Storm Report #2 (pdf)

The prior, 'tentative' Storm #1 earlier this month did, in fact, linger just long enough with snowcover over more than half of Senator Beck Basin, albeit very thin cover, to 'count' as #1 . We will find that Storm #1 layer in our snow profiles for the rest of the winter, at least at the higher elevation Senator Beck Study Plot. Now we're really in business with a half-meter of snowcover and more over the entire Basin.

A special thanks to the many of you who have made your Winter 2014/2015 Friends of the CSAS contribution ... kudos to you! For those who would also like to contribute, and sustain our data collection at Senator Beck Basin, see: snowstudies.org/friends1.html. You can donate through PayPal or simply send a check to CSAS at the address shown.

Winter Storm #1: November 2-3, 2014
After a dry October, with only a couple of very minor and short-lived snowfalls that quickly melted back to the ground, we finally received a snowfall last weekend that may comprise the basal snowcover in Senator Beck Basin for this winter. We'll see - we're in for a sunny period ahead and we may lose this snowcover too. But, so far, the new snow is hanging in there over the majority of Senator Beck Basin and at our two study plots. So, tentatively, I'll consider this event as Storm #1 at Senator Beck Basin for winter 2014/2015. Storm Report #1 (pdf)