Beautiful Day and a Great Week

2014-09-09 19:08:48.000 – Caleb Meute,  Summit Intern

110 Miles of Visibility!

Well today has brought with it some of the driest air I have seen up here on the summit since arriving in the middle of May. Currently, the dewpoint is 8.3 degrees F below zero making for a relative humidity of only 10 %. This is leading to a spectacular view of 110 miles. Being able to report that type of visibility is unique to our station. We can actually report up to a maximum distance of 135 miles when the summit of Mount Marcy is visible in the Adirondack Mountains. I am still learning the names of different peaks surrounding Mount Washington, but they serve as the perfect visual aids for us to measure horizontal visibility.

This week has been truly spectacular as we have seen different weather phenomena that make living up here so interesting. We have experienced undercast conditions which is where there is a layer of clouds beneath the summit resembling an ocean of gray when you look out. Friday, the skies were clear and you would think that our visibility would have been exceptional, however due to an extremely thick layer of haze, horizontal visibility was 20 miles or less throughout the whole day. Saturday, a cold front brought showery weather to the summits, and severe weather, which just missed us to the south. Severe thunderstorms from this weather complex did end up moving through southern New Hampshire in Hillsborough County leading to a microburst of 110 mph. Luckily, no people were injured from this storm, despite downed trees being reported with rootballs up to 15 feet in diameter! In the wake of this cold front, much cooler air infiltrated the region causing the coldest temperatures that I have felt up here yet. Perhaps this is a wakeup call for me to prepare for the severely cold temperatures of the approaching winter season.

I will end with a quick anecdote. I was working on the 36 hour forecast, Sunday, with the help of our staff meteorologist, Tom Padham. When I got to the overnight period I was forecasting wind chills between 20-30 degrees F which seemed pretty intense to me. I decided to describe this wind chill range as “bitter” which gave Tom a good laugh. He instructed me to remove that adjective as, per Mount Washington standards, bitter is way less than a 20-30 degree F wind chill. He then mentioned that towards the end of our winter season, when wind chills are rising back into the 20-30 degree range, I will be describing them as a “relief” to our cold temperatures. I think I need a better coat.

Caleb Meute,  Summit Intern