13:03 Sat Oct 19, 2019
Recapping Our First Major Storm of the Fall
The past few days have the seen the first real winter-like conditions here on the summit in this month of October. Our return to winter (for now) is due in part to an impressive coastal storm that my co-worker Jay posted a great blog leading up to. The storm was notable in my mind for its very strong easterly winds, extremely low pressure, and also some pretty horrendous icing conditions on our tower!
The strongest winds were on the front end of the storm, where a low level jet maximum was located. Mount Washington seemed to just miss out on the core of these winds, which remained a bit further south and east of the area. Despite this, winds were still quite impressive for the time of year, peaking at 128 mph around 5:30 AM Thursday morning. During the several hours leading up to the peak gust freezing rain, fog, and 100+ mph winds led to 1-2 feet of solid glaze ice on our tower. This ice was very difficult to remove due to the wind direction, and once it was dislodged we had to be very careful to make sure no one was downwind where that ice was now quickly heading!
Intern Laura Kee holds a large block of rime ice on top of the tower after clearing the morning of 10-19. Ice of this size or larger was being knocked off the tower each hour yesterday!
The majority of the day Thursday the center of the powerful storm stalled near Lake Winnipesaukee, with winds decreasing as the storm slowly filled in and weakened. Temperatures climbed just above freezing and stalled there for most of the day, thankfully bringing an end to the freezing rain and switching things over to plain rain. By the early evening the system began drifting offshore very slowly, allowing for colder air to move back in and light rain showers to change to light snow showers. The warm side of the storm had now passed, and our first real taste of winter was about to begin.
By the time I had awoken Friday morning around 5:30 AM it felt like we did a fast forward to January, with the familiar hum (to me at least) of hurricane force winds outside and the clinking of night observer Ryan de-icing the top of the tower. This morning temperatures were well below freezing at 24°F, with heavy riming conditions and snow falling instead of the freezing rain from the day before. Winds were already gusting over 100 mph by the time I began my observations, but increased further by 7 AM with the peak gust of 114 mph from the NW occurring shortly after 7:30 AM. The riming conditions during the morning were right up there with some of the worst I’ve ever seen in my 7 years on the summit, at one point accumulating at a rate of nearly 6 inches of ice in a single hour.
Intern Laura stands next to several feet of rime ice for scale, and enthusiasm!
After clearing out of the clouds early this morning, we’ve finally been able to take in the scenery and also snap some photos now that the winds are lessening. The summit picked up an impressive amount of ice along with 4.3” of new snow, making it look much more like the winter season than October. With temperatures expected to warm into the 30s today and even 40s by Sunday this snow and ice will likely be gone by the end of the weekend. For now, it’s a beautiful reminder of the winter season to come!
Thomas Padham, Weather Observer/Education Specialist