09:18 Fri Nov 16, 2018
What A Start to Winter!
Although it may not technically be meteorological winter just yet, which starts in December, we are already off to a great start to our snow season here on the summit of Mount Washington. Our snow season runs from July 1st through the following year to June 30th, with each winter centered across the snow season. This is a much more accurate way of looking at a yearly depiction of snowfall and the variations from one winter to another, especially for locations that see snowfall over many months of the year like Mount Washington.
A Snow-Capped Mount Washington from Jackson, NH on October 14th, 2018
With that said, we are heading into the heart of the snow season, where the vast majority of our precipitation falls as only snowfall with very infrequent rainfall. As of this writing, snow is currently falling with a departing Nor’easter, and we’re expecting at least another 6” of snow over the next several days. 28.3” has fallen for this month of November so far, and we are well on pace to have an above average month (38” is average for November).
Roughly 10" of snow is in place across the summit as of 11/15/2018
For the total snow season the summit is now up to 81”, roughly 3 feet above average! October in particular was a great month from a snow standpoint, ending up as our second snowiest on record. Unfortunately, most of that snow is no longer on the ground up here due to a combination of high winds and some melting and rain. The winds have also been above average these past few months, with an impressive 19 days with hurricane force winds in October, more than half the month!
Even if the rest of the winter turns out to be just “average” there’s still plenty more snow to be had. “Average” snowfall December through May should total another 19 feet, and there’s always the potential for much, much more! With the real winter season just around the corner, this observer hopes to see a whole lot more snow up here soon!
Weather Observer/Research Specialist Taylor is excited for winter too!
Tom Padham, Weather Observer/Education Specialist
05:16 Wed Nov 14, 2018
"What do you guys do on your off weeks?"
A question we’ve gotten from a couple Facebook lives this week was, “So what do you guys do on your off weeks?” I love this question because most of the time we are asked about operational questions. And don’t get me wrong, we love answering those. However, we’re also human beings, and we all do a bunch of unique things in our off weeks. Sure the mountain is immaculate, but we’ve been up here since last Tuesday (With a chance of us having to stay up until Thursday.) So, it’s had us making plans, and getting ready to enjoy our off time. This shift has amazing human beings up here, and I thought it’d be fun to dip briefly into what they like to do on their off time, and what I personally do when I’m down.
Ian is always someone who you can find in a park, probably around southwest NH, tossin’ pokeballs in Pokémon go. That game is incredibly fun, especially when you are looking to take a leisurely stroll around town. Adam is the kind of guy who’s ready to go on a bike trip across the entire US. He’s always one to say, “Welp, I’m gonna go on a bike ride.” Then disappear for 4-5 hours. Zach has an excellent job at EMS her works, and often times will hike around with his ol’ AMC palls.
We normally all meet up as a shift at least once on our down week, and sometimes we’ll go on individual endeavors with one another. We genuinely enjoy each other’s company, so it’s always fun to do things without the pressure of taking Observations every hour! For example, Ian and I visited Fun Spot in Laconia a few weeks back. We had a blast for pretty much the entire day. If you have not been, I highly recommend you head on over!
Adam and I live together, so we’re always heading out together to explore the great state of NH. When we’re not hanging out together, I have a few hobbies I tend to gravitate toward. I love creating stained glass pieces; it’s been a lovely hobby I’ve had ever since high school. I’ve slowly branched out to more intricate works, I’m even working on right now of a Barn Owl (One of the most beautiful creatures in my opinion). Here is a work in progress picture from about a month ago:
Again, I cannot express how much I love working here, but we all need some off time. It’s been a joy to work this unique schedule; and have the time to really plan out trips in my “Mini-Weekly Vacation.” This winter I’m hoping to hit the slopes like the rest of you. You’ll probably find me around Black Mountain or Cannon digging into that powder.
Thanks for reading! If you have any more questions about the Observatory, don’t hesitate to message us! Have a great day everyone.
Christopher Hohman, Night Observer
13:48 Sun Nov 11, 2018
A Windy Start to Winter
This year it seems like we have seen a greater frequency of strong storms that produced 100+ mph gusts up here on the summit. Taking a look at this year, as of today November 11th, we are sitting at 8 days since July 1st where we have hit 100 mph. This does not sound like much but usually our frequent high winds don’t start coming until December, then we see it much more regularly. Last year was also fairly windy but there was 7 days that had 100+ mph winds by this time.
Looking back at our history, the next year that tied or exceeded our total so far was 2005, where there were 10 days of 100+ mph wind gusts by this time of year. For the last 20 years or so, the amount of 100 mph days we have seen up to this point has averaged pretty low, averaging only 4-5 days. The 1980’s saw the most where most years were in the 8-10 day range.
Out of curiosity, I took a look at some of the historical weather maps on days where the winds got quite high during the 1980’s and there were pretty consistent large storms that traveled up the coast or came out of the Great Lakes region. Many of the storms that were seen multiple times a year in the 80’s would be a significant storm to even have just once here. I did not have the time to go through and see if I can find any sort of correlation with the ENSO (El Nino/la Nina index), NAO (North Atlantic Oscillation), or the AO (Arctic Oscillation).
These oscillations influence the weather, with the NAO having the biggest impact on East Coast weather. There have been projects done in the past correlating these oscillations with snowfall and precipitation up here on the summit but it would be fun to do a more wind climatology and see how much of an effect these oscillations have on the winds up here!
Adam Gill, Weather Observer/IT Specialist
14:17 Sat Nov 03, 2018
A Unique Instrument for a Unique Place!
In anticipation of high winds tonight on the summit, it seemed appropriate to discuss how the observatory measures wind speeds in such an extreme environment. Since Mt. Washington experiences wind speeds that exceed 100 mph every three days in the winter as well as rime ice accretion up to 9 inches per hour, the observatory is forced to use an unusual instrument to measure winds. Typical anemometers such as a three-cup anemometer or a vane anemometer would not be able withstand such extreme conditions. With an average wind speed of 35 mph, such instruments would wear out very quickly from spinning so fast. Additionally, with the large accumulations of rime ice, the propellers or cups would get clogged very quickly and either break or not work properly. So instead we use a pitot tube.
The pitot tube was initially invented by French engineer Henri Pitot in the early 18th century but it was later modified to its modern form in the mid-19th century by French scientist Henry Darcy. It is used to measure fluid flow velocity, most commonly used to determine the airspeed of aircrafts. The basic pitot tube consists of a metal tube pointing directly into the fluid flow. We use a pitot-static tube which is just a pitot tube with two ports, pitot and static ports. The pitot port measures the pressure of the air ramming into the tube known as the total pressure. The static port measures the static pressure of the air sliding along the tube using small holes along the side of the tube. The diagram below shows the placement of both ports.
The pitot tube is able to output air velocity using a fundamental principal called Bernoulli’s principle. Bernoulli’s equation states that the Total Pressure = Static pressure + Dynamic Pressure. Using the measured static and total pressure, one can thus calculate the dynamic pressure. Bernoulli’s principle also states that the dynamic pressure can be related to the velocity of the fluid. So calculating the pressure differential between the static and total pressure will give you the velocity of the airflow! Connecting a tail to the end of the tube makes sure that the tube always points into the direction of the wind meaning it can always accurately measure the wind speed regardless of direction.
This special anemometer has several perks. First, this instrument does not have any moving parts like a propeller. This means that it will not be jammed with ice as temperatures dip below freezing nor will it wear out from high wind speeds. It also has the huge advantage of being able to be heated which helps to combat the large quantities of rime ice that collect on every surface.
With such unique conditions present at Mt. Washington, we use a pretty unique instrument. Hopefully you learned a little something about it from this blog post and hopefully we see this instrument recording some pretty high winds tonight!
Chloe Boehm, Summit Intern