Its been awhile since the last post and I apologize. A lot has happened on the Berkshire East and personal front. Since the last blog visit we’ve had holiday snow, rain, ice, snowmaking, more snow, more rain and a lot more snow making. In the middle of it all, I got the winter bug that was passed around and it took me out of commission for awhile.
Last week (January 11-13) in review. The weather got weird, warm and the mountain got dinged up pretty good. We spent all day Friday the 13th, putting everything back together again, while getting the snowmaking reset for a big 4 day push.
All the while the weathermen were telling us that we were staring down the barrel of a water monitor which poised to bring an inch of rain, 50 degree temps and a 10-14 days of non freezing temps to New England…
Until in typical stubborn New Englander fashion, the New England cold air is sticking around a little longer than weather guys expected and thankfully, it looks like we are going to get some snow and ice.
With this change in forecast what could have been a tough hit, looks like a net gain to the base. Here is a link to the Active Winter Weather Advisory. After this storm passes the longterm temps are still warm / seasonal, but heck, who doesn’t like skiing when its 40 and sunny with freezing temps at night? Personally, I think that the rest of the week and into the weekend should be some of the best skiing of the year (so far).
Late next week (late January 20’s), we’ve got a nice pattern shift which the weather guys say should bring us to below seasonal temps. This should ’T’ up February for a great start. Pattern shifts are often associated with storminess, so hopefully we get some plowable snow in that timeframe.
As an aside, my weather comes from a mix of sources. Our longterm number 1 guy is John Hawkridge, who not only is a great forecaster, but a personal friend of our families. Beyond John, I use a mix of sources and look at trends. I have a three to four time a day habit of checking the following weather apps, The Weather Channel, Accuweather, Underground (same as the TWC, but Weather Underground features the Wundermap which shows crowd sourced weather stations so you can see real time temps around New England). I don’t put too much faith in the apps beyond 48 hours, but I figure the temp displays are outputs of computer models that are good enough to show you trends, i.e. “the 5-7 day temps appear colder today than yesterday, maybe I should look into this more.”
Here is a link to an article on the accuracy of the weather apps / pages, or you can skip the link and feel confident in saying that Weather Channel and Weather Underground have a tight lead over Accuweather in a 5 year race. I’ve also read, but can’t find the link, but I’ve read frequently that Accuweather has the best cold temp forecast…
There are also a mountain weather bloggers who write about weather. I prefer Josh Fox with Mad River Glen. Part of this might just be nostalgia, because we used to crush Mad River on powder days when I raced at Middlebury and I spent the better part of the famous Valentines days storm there in about 40 inches of light powder, skiing amazing lines and getting frost bite. Anyway, Josh is great at describing the global inputs such as the AO, MJO, PNA, and other meta patterns that effect our local weather.
Locally, you can’t beat the Scientific Forecaster discussion from the National Weather Service. I find it by scrolling to the bottom of the Weather Underground forecast page. This gives a detailed written explanation to the weather. It’s my experience from reading enough weather bloggers that a lot of them just jump this feed from a real forecaster and repurpose that persons good work for their own clicks.
Dave Hayes the Weather Nut has an extremely popular local weather page on Facebook and he is very attentive to minute to minute details of a storm. His passion bleeds through to his work and its fun to watch the snow totals pile up as folks use the comment section of his posts to share town by town and street by street weather info.
If you feel like it, tell me what your most consistent source of weather on this survey from Survey Monkey.
HOWEVER, WE DON’T NEED PLOWABLE SNOW TO MAKE GREAT CONDITIONS!!!
If I don’t say so myself, we’ve got a pretty sweet snowmaking system. Honestly, I’d take it up there with just about anyone. The fan guns make snow of a quality rivaling the best natural packed powder and we can move a lot of water and our new sticks optimize the efficiency of our system by their judicial use of electricity and optimize our use of pumped water. Additionally, our new Prinoth groomers have the best tillers available and the guys behind the sticks no how to use them.
To make sure these blog posts aren’t too ra ra and just because I can, I’ve spent a little time putting together a Glossary of Terms and phrases on snowmaking for you. Some of its basic, and some of its scientific, and some of the science I’ve botched (don’t bother pointing out the errors because of the tenacity of wordpress spammers I don’t post submitted comments), but hopefully it lends some clarity to the process.
Though maybe someday we should do a mailbag, strike the above comment, if you have a question send it in to the comments, I get the emails…
So here we go.
Snow Making: (man made snow, as opposed to natural snow) is the process by which, water (which tends to freeze in cold weather) is pumped under high pressure through miles of pipes while trying to freeze solid every step of the way. At the gun, it emerges through specialized nozzles that atomize the liquid into a fine spray where it mixes with cold air, freezes into small pieces of ice and is lands (ideally) onto the trail. Basically, the required inputs are water, cold air, and energy.
When nature doesn’t send us natural snow, snowmakers step in. Using a mix of fan guns and stick guns, multiple pumps and our pipe infrastructure, the Berkshire East crew is pretty well prepped to make a lot of snow.
Some interesting properties of water per the snowmakers.com website.
Water is a unique material, it expands when it freezes and it has high heat of fusion, thus your ice cubes float and last a long time. Heat of fusion means that one can cool a pound of water say from 65°F (18.3°C) to 64°F (17.8°C) or 34°F (1.1°C) to 33°F (.6°C) by removing 1 BTU. But to convert one pound of liquid water at 32°F (0°C) from a liquid to one pound of ice at 32°F (0°C) requires the removal of 144 BTUs. In summary, a large amount of heat removal (cooling) is required in snowmaking. Also, water can be cooled well below 32°F (0°C) and still stay a liquid unless it is nucleated. This phenomenon is called supercooling.
So a snowmaking machine (a) breaks the water into small particles, (b) cools the water to 32°F (0°C), (c) removes the heat of fusion, and (d) nucleates.
[This is where the fan guns come in handy, they spread out and mix the water so much with the cool air, more water can convert to high quality snow]
Berkshire East can convert about many hundreds of tons of water into snow an hour and lay down many acres of snow, several feet deep in a night.
The following weather variables are critical to snowmaking.
Temperature: We all know that water freezes below 32 degrees, but it is not that simple, there are a lot of inputs such as humidity, pond water temp, etc that need to line up before you make good snow. Pond water is warmer than 32 degrees, so a lot of heat needs to be removed from the water to convert the liquid water to snow crystals by the time the passes from the nozzle to the gun and hits the ground. Humidity, can effectively raise or lower the freezing point of water via the wet bulb.
Wet bulb: The wet-bulb temperature is the lowest temperature which may be achieved by evaporative cooling of a water-wetted (or even ice-covered), ventilated surface.
Basically, if its 25 degrees and 90% humidity, you’ll have a tough time making snow, but if its 32 degrees and 10% humidity, you can make snow all day. A lot of times we will be making snow and at first light the temperature rises the capacity of the atmosphere to hold water increases and the humidity drops. So essentially, even though the temps warm up the wet bulb stays the same or drops, and your snow making capacity is unchanged. Amazingly, there are times we make snow above 32 degrees in these conditions.
Wind: Sometimes it is so windy when we make snow that we make snow Hawley and Ashfield. Ideally, its calm, either way, wind is a factor.
Cold Air Damming, Inversions, and Capping Inversions: Weather terms. Complex enough, but wikipedia does a great job of explaining them if you are interested. At Berkshire East, these happen frequently. Basically cold air gets trapped in the valley as warmer storms pass through, resulting in snow and ice while our neighbors get rain.
Snow Making Basics and Glossary Continued:
There are many parts and pieces of a man made snow making system. Here are some of the equipment terms used.
Nozzle: When the water leaves the snow gun it passes through the nozzle which atomizes the water. Once the water is atomized it cools quicker, freezes faster and is converted at higher rates to ice droplets. These can clog and the clogs can cause spray pattern issues, effecting snow making quality, most snow guns use onboard water filters.
Nucleation: Nucleation occurs when water freezes around a seed crystal. In a snow gun, nucleation occurs in the snow gun around one of three things; 1) bacteria in the water (such as pseudomonas syringae) 2) ice crystals formed by expanding forced air 3) introduced commercial particulates to act as seed crystals. Without the seed crystal, water can supercool below the freezing point and exist in a liquid state until a seed crystal reveals itself.
The common bacteria that helps nucleate snow, Pseudomonas syringae is pretty cool. Many ski areas use a freeze dried product of this bacteria to help in early season snow making. This bacteria is pretty common and basically binds water in a really efficient (nucleate) way, and allows snow crystals to form in warm temps.
Stick Gun: A stick gun is a tall pole. You will see that Berkshire East has added some sticks to compliment the fan gun fleet. These guns use less electricity, but lack the throw and marginal temp performance of fan guns. Stick guns have limited throw and are very sensitive to the wind.
Fan Gun: Fan snow guns use propellers to throw the snow and provide hang time for mixing and freezing. Fans are known for throw, high capacity in all weather conditions, low wind sensitivity and overall performance. Fans can be portable or fixed position on towers and swing arms. The fans are more popular in area with marginal weather conditions and wider slopes.
Water Pumps: Berkshire East has an internal network of pumps to transfer water from the base area to the top of the ski area. These high pressure pumps are essentially the four chambers of the heart. They take the most energy to run, without them we shut down, and its imperative that they operate efficiently.
Physicality of the work: Snowmaking is a physically challenging endeavor. The days and nights are long, the weather tough and its heart, it is an industrial process that occurs in a frozen, dark, windswept mountain where we change the physical state of water to ice. The trick is to get the water to phase change after the nozzles of gun, not in the miles of freezing pipes before that point.
The complexity of a snow making system invites issues and inevitably you are constantly dealing with weird, unique problems on an almost nightly basis. But the work is fun, interesting, challenging and when you get out and arc some turns (or simply watch others) on the surface you made, it can be really rewarding.
Anyway, thats the news from Berkshire East. Pardon the lengthiness and the probable spelling / grammatical errors. I am trying hard to provide relevant content and not ski area propaganda.