There's nothing about this at the Mt Washington web site, but I joined and posted to their forum:
Title: WMO lists new wind gust record 113.2 m/s (253 mph; 220 kt)
I know of some event that challenged the MWO record, but I'm not sure if this is the same event or not, I think not. It is from 1996, I'm not sure what took them so long to investigate, this sounds like a new declaration.
http://wmo.asu.edu/world-maximum-surface-wind-gust
http://wmo.asu.edu/
http://www.wmo.int/pages/mediacentre/infonotes/info_58_en.html
The folks at Mt. Washington view their record with great reverence, I'm surprised the site is silent about it.
