Tuesday, March 27, 2012

What Are the US Snowfall Records?


Sounds like an easy question, but the answer isn't so simple.  

I figured I'd go to the National Climatic Data Center, and sure enough, I found a web page for "National Snowfall and Snow Depth Extremes."  Ah, an answer.

Source: NCDC
But, years of wasting time reading about snow caused me to scratch my head about the numbers above.  I seemed to recall that California had some prodigious snowfalls.  Indeed, it's easy to find web sites with conflicting numbers from California.  In particular, many claim that the monthly snowfall record is actually 390 inches at Tamarack, CA in March January 1911 and the single storm snowfall record is 189" at Mount Shasta Ski Bowl from Feb 13–19 1959.  

I'm not sure why the difference in the monthly snowfall record, especially since it appears the NCDC data above includes an analysis of March 1911.  Perhaps the March 1911 data was deemed suspect?  I also wonder if the Mount Shasta record might extend over slightly longer than 7 calendar days and thus doesn't meet the bar for a 7-day records.  

Got any clues?  Let me know.  

9 comments:

  1. Silver Lake, CO has the highest 24-hr (not daily) snowfall record of 76", beating Georgetown's 63". Georgetown has the record during a single day (midnight to midnight) while Silver Lake, CO has the record for any 24-hr time period. Monthly Weather Review article here: http://docs.lib.noaa.gov/rescue/mwr/081/mwr-081-02-0038.pdf

    ReplyDelete
    Replies
    1. Joel - I should have caught that one. I suspect that NCDC list is based solely on 24-h coop data in their archives and not other observations. At issue is where can one find the official snow records online. It shouldn't be this hard!

      Jim

      Delete
  2. I have always heard Mount Baker wins the prize in one season with 1,140" in 1998-1999. http://en.wikipedia.org/wiki/Mount_Baker

    ReplyDelete
  3. Depends on what qualifies as an official recording station. Baker snow depth sits at 300+ last I looked.

    ReplyDelete
    Replies
    1. To qualify as a record, the data doesn't necessarily need to be taken at an "official" station, but the methods need to be verified. The question is -- where can one find the official records online on a site that is supported by the verifying group (presumably NOAA).

      Delete
  4. Um, when I checked on the daily data for Tamarack's records it didn't appear reliable. For example, at the same time Tamarack recorded 394 inches of snow, they also recorded 39.40 inches of SWE (the correlation seems a bit unlikely). Of course, this could mean they just estimated the SWE from the actual snowfall....Also, the 454 inch deep snowpack considered the record for the U.S. recorded at Tamarack that March 10, 1911 isn't listed in their daily data and is definitely high considering they had only received 589 inches of total snow that season when the depth was recorded. These points make me suspect that station.... I've also heard the record snowdepth is 367 recorded at Paradise Ranger Station. Here are the links for the Tamarack Data:
    http://www1.ncdc.noaa.gov/pub/orders/22528.pdf and
    http://www.ncdc.noaa.gov/cdo-web/search
    Sorry this is so long!

    ReplyDelete
    Replies
    1. Ben:

      Yeah, that 394 to 39.40 SWE is your classic 10-1 conversion. Unfortunately, this used to happen a lot. They probably measured the snow and did the SWE by dividing by 10.

      Scanning through the Tamarack data on the top link, the 394" is recorded in Jan 1911. Curiously, most web sites list 390 inches as the "record" that month. I just noticed I incorrectly said it was Mar 1911 in my post. I'll update that.

      I've never believed the 454" snowpack figure. Maybe there was a wind drift at that depth somewhere.

      We need a historian and data curator to dig into this for us!

      Thanks,

      Jim

      Delete
  5. I finally found it. http://www.ncdc.noaa.gov/extremes/ncec/ lists the existing "official" records and includes a 451 inch snow depth from Tamarack on March 11, 1911. I'd like to see a report on the acceptance of this record, although that may require some digging.

    ReplyDelete