Back to Truck and Van Season

2019-04-26 12:30:33.000 – Adam Gill, Weather Observer/IT Specialist

Winter seems like it has come to a fairly abrupt end up here on the Rockpile this year which is quite the difference from the previous few years. We went from having plenty of snow on the mountain from top to bottom taking the snow cat from the base up to just using the truck and van the whole way in only a matter of weeks. All this warm weather and rain melted the snow fast and allowed for the Auto road to make significant progress on clearing the road. There was a little bit of ice just above tree line that we had to put chains on for but other than that, it was a smooth ride up the mountain! Cragway corner was also cleared so we got to do our annual photo at the snow wall this year. It was a little shorter than previous years but that could have been due to how much snow melted with the rain and heat last week.

Our 4X4 van sitting at Cragway Corner where the snow wall is usually the deepest

As much as I like to take the snow cat, by the end of the season it is nice to be able to get up and down the mountain in a short period of time. Now that the road is clear and the ground warming up, even if we get more snow, we will be able to plow through it so the snow cat season is officially over! The only reason we may have to use it is in the off chance that we get another snowstorm like we did for Mother’s day 2 years ago where we got over 30 inches of snow in a little over 24 hours.

Now winter is not over yet even though snow cat season is over for the year. The summit usually will receive snow on a regular basis all the way into June. The last several years have experienced large snow storms that bring a foot plus of snow in the late season. Taking a look ahead, we are in a stormy weather pattern with many quick moving storms expected to move through over the next few weeks. This storm coming in will have mostly rain associated with it as warm air is pumped into the region through the low level jet. It is fairly intense for this time of year with its central pressure forecasted to fall down to around 985 millibars. Cold air wrapping around the back of the low will bring in some much colder air with temperatures falling all the way down to the single digits above tree line. There will be enough moisture to support snow but accumulations are not expected to be great.

Looking further ahead, it is looking like our spring/summer like weather we have been seeing in the mountains will be coming to an end. Below is the European models outlook for the North Atlantic Oscillation (NAO). This indicates that it will go negative for the last few days in April and first week or so of May. When the NAO is negative, blocking high pressure exist up near Greenland and that will force air south out of the Hudson Bay area so usually when the NAO is negative, New England sees colder than average temperatures. It is not guaranteed but the probability of cold air and even snow is possible. In order to get snow we will need a storm to come through that will bring precipitation and clouds. The sun is strong enough at this time of year to really warm things up if there are no clouds, even if we have cold northwest flow out of Canada.

The 10 day forecast for the NAO. When the NAO is negative, there exist a greater probability of seeing below average temperatures in New England

We are getting to the point of the year where it takes an exceptional weather event to get accumulating snow in the valleys but it is possible. Over the higher terrain it still does not take much to produce wintery conditions until early June, though any snow and rime that we do see will melt the next sunny day we get.

Adam Gill, Weather Observer/IT Specialist