Icy shift change

2010-11-10 23:44:28.000 – Ryan Knapp,  Staff Meteorologist

An icy ride up.

Another Wednesday, another shift change for the summit crews. And like the past few shift changes, my shift returns to an altered summit view. Heading down October twentieth, there was an average of 6 inches of snow, ice and rime on the ground but upon returning on the twenty-seventh, it looked and felt more like June than it did late October as warm rain diminished the snow pack to nearly zero. Over our last shift we had once again built our snow base back up to about six inches by the time we left on November third but upon returning today, most of that snow was gone and in its place is about three inches of sleet and glaze ice. And this glaze ice is covering everything up here. Covering is putting it lightly; the ice is clumped, globed, clinging, strewn, coating, sealing, squelching, and layering everything up here. If the subfreezing water could get to it, it has glaze ice on it.

As you’ve been reading in the past few days and during other icing events, working in this kind of the weather is, in my opinion, the worst type of weather to work and operate in up here. It makes for slippery conditions. It makes for heavy chunks of ice, not rime, flying about. It makes for (typically) eastern winds, a direction the building isn’t really designed to handle. It knocks out communications and sometimes instrumentation. It’s dangerous, it’s painful, and it’s disruptive when it is occurring and for several hours, if not days after it lets up and things start to thaw or sublimate.

Today though is the day of transition, it’s still icy but trending towards a return of ‘normal’ (however you want to define normal as). Fog lifted early this morning as high pressure started to build in and with it a drier and slowly warming air mass. The dry air allowed for plenty of sublimation that started during the day and is continuing tonight. And in the coming days, the building high will further sublimate and eventually evaporate and melt the ice leaving yet another altered summit scene by this weekend as we flirt with possibly some record heat. And as things melt, evaporate or sublimate, the ice will continue to change creating an ever evolving landscape up here and by next Wednesday, the summit scene the crew left with will be completely new and different for them to experience and talk about.

Ryan Knapp,  Staff Meteorologist