A quick follow-up to my last post is in order after some helpful comments from Jim Green (who has an interesting blog post on snow loads here.) Jim has observed a large shortfall in reported precipitation at the Haines ASOS, and he proposes a similar deficiency in the data from Yakutat. I think this is a highly credible suggestion given Jim's information, as well as data from the Yakutat CRN site.
I'm not sure why I didn't check this before, but indeed the Yakutat CRN - which is located right next to the airport - reported much more precipitation in November and December than the ASOS instrument. See below (but the CRN has missing data since January 6).
From November 10 through January 5, the CRN reported over 3.5" (32%) more precipitation than the ASOS, and if we apply this ratio to my earlier estimates, we arrive at perhaps 150" of snow, instead of 100-120".
Jim also points out the following photo from January 11, the day Yakutat declared their emergency. The snow depth appears to be at least 60", which is consistent with well over 100" of total snowfall. And if Jim's snow density measurement applies here, then Yakutat's snow pack may have had at least 18" of liquid-equivalent stored in it; this suggests that perhaps even the CRN was reporting too little precipitation. Snow water storage of 18" translates into nearly 100 lbs of snow load per square foot.
Not gonna complain it is cold today.
— Eugene Wilkie (ReesusPatriot) (@ResusCGMedia) January 11, 2022
Glacier Bear Lodge
Yakutat, Alaska. pic.twitter.com/npJ2mYcIJo
As an aside, I compared November-December precipitation totals between the Yakutat CRN and ASOS, and in the 3 years with complete data, the CRN reported 12%, 33%, and 30% more than the ASOS. So it appears this is not a new problem with winter precipitation amounts, even in more typically rainy years.
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