Freezing Rain

2006-10-01 23:10:57.000 – Jon Cotton,  Observer

LL Bean Red

Today the summit got hammered. If you looked at the forecast today and then visited, you know the difference in what happened. The rain forecast for the state was easy. At the higher elevations the type of precipitation to expect became trickier to determine. All the models had us in the mid 30s with the freezing level about 800 feet above us through the day. We were supposed to go above freezing and confidently stay that way through the night. The hesitation was how cold would the air be above the summit and would there be enough warmth to thaw the precip into rain. The odds were high in the favor of rain. It was clear however that we were right on the border.

A forecast is a planning tool. “What am I likely to expect from the weather today and how can I be prepared for it”. Above treeline in the transition seasons it is critical to be appropriately equipped. With such a borderline of temperature and precipitation, the safe call was for “mixed precipitation” meaning liquid and/or frozen.

Day dawned at 33 degrees with rain. By 9am, we were below freezing and the liquid portion was finished for the day. Precip switched to snow and ice pellets, then freezing rain, back to snow, some more ice pellets, then freezing drizzle finished off the set. Around noon the freezing level was around 5600′ – quite an important difference from the model predictions. Total snow fall today was .6″, water equivalent of everything was .21″ and we had multiple encores of both riming and glazing. Yikes. It was a nasty day up here. Oh, our peak wind was 77mph at 1:18 this afternoon. That was a surprise as well. Welcome October.

Our volunteer cook for the week is a photographer. She took these the other day on a walk around the summit.
The Observatory Tower
The Cog Train

Jon Cotton,  Observer