If that ski jacket you own comes with one of those powder skirts you better make sure it works because you can put it to use this weekend. The ghosts of Valentines Day have been put to work and are producing an event this Sunday which is very analogous to February 14th. Who would've thunk it !! Certainly not me since apparently someone injected with me the "glass-half-empty steroid" prior to that pre-season report I gave last month. But who really cares what was said and when. Without a doubt the best responsibility I have maintaining this blog is to hype a storm such as the likes of this one.
The Storm
Dig back through the archives of the blog or in the recesses of your mind and recall that the Valentines Day Blizzard deepened to about 978 mb and tracked directly over the city of Boston. It was a juicy system also supported with moisture from the gulf, amplifying/digging upper air dynamics and a healthy supply of fresh low level cold air from eastern Canada. This system has about every part of what Valentines Day had including the cold air which will arrive on brisk northwest winds by Saturday morning. The difference would seem small but it does make the forecast a bit trickier. This storm, according to the models will track from Philadelphia, to Hartford to Worcester to Portland, Maine. In other words, if things go according to the plan, the storm tracks west of Boston bringing the above freezing temperatures in the mid-layers of the troposphere closer and eventually over MRG. So recall that the sweet spot for Valentines Day storm was at the base of the Single Chair and I marked the spot with some red tape if anyone wants to take a look (joke). For this event, the sweet spot will probably be closer to Mt. Marcy in the Adirondacks. That is quite alright though because Mt Marcy is really not that far away.
The Details
High clouds from the rapidly strengthening system may arrive as early as the afternoon Saturday which will help to keep temperatures at or below 10. Calm winds and the new snow received throughout this past week will help to make it a pretty good day to ski. Good visibility will do wonders for the view as well (won't be much of a view on Sunday). My guess right now is that the snow commences around 8 am Sunday with a minimal accumulation by first tracks time if any at all. I know a few inches would be nice but the timing here isn't bad since the first 6-8 hours of the storm will be the part which does not feature as much wind thus putting us less at risk for any wind holds. Believe me once this snow starts coming down by mid-morning it will accumulate at a rate of between 2-3 inches an hour and this should persist throughout the end of the day. In other words, it will be all about last tracks since that 3:30 pm run I know everyone plans to take will feature nearly a foot of new powder to ski in. In all seriousness though, please drive safe if your traveling Sunday and consider staying at a lodge and taking the day off Monday. It will be a epic day to ski but a miserable day to travel particularly during the evening when the wind intensifies. The interstates should improve dramatically by late Monday.
Sleet Factor
Some have accused me of sleet-a-phobia and I will argue that I have none. I am just an east coast realist as far as weather is concerned and I have also looked at the temperature cross sections about 10 different ways. The change to sleet will occur during the evening and last for a period of around 3-6 hours Sunday night before we go back to a period snow prior to first tracks Monday. Snow and sleet accumulations will be in the 16-30 inch range with much predicated on the duration of the sleet. We will not get any freezing rain however which means none of that dreaded breakable crust. What I can say is that this storm assuredly puts the mountain in fantastic shape heading into the X-Mas holiday as far as the base is concerned.
Next Week and Beyond
The snow on Monday will taper to snow showers and flurries. It will be blustery and quite chilly as it always is following a big storm such as this. On Tuesday the winds diminish but remains cold with temperatures below zero in the morning and in the teens during the afternoon. On Wednesday, a clipper system will bring limited amounts of moisture to the region which will likely be deposited as a small accumulation of snow and giving us a powder day (either Wednesday or Thursday).
Now I hinted at a potential pattern change of a possible adverse variety late next week and indeed some of the teleconnection indices specifically the PNA will turn unfavorable by the winter solstice. Data however from both the medium range model guidance and the ensembles seems to be delaying the effects of this pattern change in the northeast and is suggesting that the turn to milder weather will be felt most dramatically in the plains. This is certainly encouraging for the time being and we will have to hope that an ample supply of cold air is still available X-Mas weekend prior to the arrival of the next system which still has a zillion possibilities as far as its impacts on MRG are concerned. More will follow on this but for now I will stay focused on the storm and will provide another/shorter update regarding that sometime on Saturday.
Friday, December 14, 2007
Wednesday, December 12, 2007
Thursday storm disappoints but the ghosts of the Valentines Day Blizzard 2007 are brewing up a sequel this Sunday !!!!
I suppose it was very foolish of me to stray from the philosophy which worked so well during the winter of 06-07. There was a disagreement on how the weather would play out this week and the European model said this and the American model said that and in light of some of the recent struggles which plagued the European model through the summer and fall I was baited into fading its reliability during the winter. I like my crow served with cranberry sauce thank you ! Actually I would prefer my crow served with about 2 feet of snow and there and things are in the works to make that a reality if you can believe it.
The European had the right idea all along. It had the right idea Sunday and had the right idea Monday when I issued the last update and now the other model guidance is in the process of jumping on the bandwagon. Wasn't it somewhere that I heard that all the cool people show up late to the party ?? Perhaps that only applies to America and not Europe. Actually us weathergeeks are often joked on for rarely getting invited to the party at all though we can still be fun and festive company, like Phillip Seymour Hoffman in Twister who was great as a tornado-chasing weather weenie in a movie full of bad science.
Thursday event fizzles to a few inches by Friday morning
Thursday's system was a disjointed one to begin and because it is a fast moving, it never had huge potential. As it turns out, the two pieces that were suppose to make up this weather system will never fully align. One storm, containing the bulk of the moisture will move quickly out of the Tennessee Valley early Thursday and be south of Long Island by the evening, too far south for any real impact on MRG. The other is a rather potent Alberta Clipper which marks the leading edge of a re-enforcing shot of cold air which will trail the aforementioned moisture-rich system to the south. Most of central and northern Vermont can expect snow from this trailing system but mainly late on Thursday or Thursday night. The dynamics from the clipper will induce snow showers and snow squalls Friday. Accumulations should be considerably lower than what was advertised in the last update, probably in the 2-6 inch range between Thursday night and Friday.
Sunday contains the real potential
The jet stream will form a nice confluence area over the Canadian Maritimes providing interior New England with a chilly day Saturday including high temperatures which struggle to get past 10 on the mountain although the winds will be relatively calm. This confluence area is a key ingredient for what is to follow on Sunday as a major weather system approaches from the southwest. It is rather incredible actually to look at the upper air and surface maps and see so many things which are strikingly similar to Valentines Day 2007, a day which probably should be memorialized at MRG. In truth, it is dangerous for a prognosticator to make such analogies 4 days from the event and some key details are likely to change over the course of the next few days. With that said, there is very good agreement concerning a big noreaster this weekend, one which will provide the coast with a mix of snow, sleet, freezing rain and ice and one which will deal interior New England and much of northern New York a sizable snow event (and wind) or one that can be measured in feet. I don't want to get carried away here because it is early and hype as a tendency to fizzle. Another update in a day or two can probably zoom in on the details a little closer and we can go to work from there.
The 20th or the 21st continues to be the date of a potential pattern change with two of the three teleconnection indices turning against us. The most dominant feature according to all indications will be a big trough in the northeast Pacific Ocean and over British Columbia. The snow cover which could be fairly deep by then could mitigate any warm-up for a time. Hopefully we can also avoid any X-Mas rain drops.
The European had the right idea all along. It had the right idea Sunday and had the right idea Monday when I issued the last update and now the other model guidance is in the process of jumping on the bandwagon. Wasn't it somewhere that I heard that all the cool people show up late to the party ?? Perhaps that only applies to America and not Europe. Actually us weathergeeks are often joked on for rarely getting invited to the party at all though we can still be fun and festive company, like Phillip Seymour Hoffman in Twister who was great as a tornado-chasing weather weenie in a movie full of bad science.
Thursday event fizzles to a few inches by Friday morning
Thursday's system was a disjointed one to begin and because it is a fast moving, it never had huge potential. As it turns out, the two pieces that were suppose to make up this weather system will never fully align. One storm, containing the bulk of the moisture will move quickly out of the Tennessee Valley early Thursday and be south of Long Island by the evening, too far south for any real impact on MRG. The other is a rather potent Alberta Clipper which marks the leading edge of a re-enforcing shot of cold air which will trail the aforementioned moisture-rich system to the south. Most of central and northern Vermont can expect snow from this trailing system but mainly late on Thursday or Thursday night. The dynamics from the clipper will induce snow showers and snow squalls Friday. Accumulations should be considerably lower than what was advertised in the last update, probably in the 2-6 inch range between Thursday night and Friday.
Sunday contains the real potential
The jet stream will form a nice confluence area over the Canadian Maritimes providing interior New England with a chilly day Saturday including high temperatures which struggle to get past 10 on the mountain although the winds will be relatively calm. This confluence area is a key ingredient for what is to follow on Sunday as a major weather system approaches from the southwest. It is rather incredible actually to look at the upper air and surface maps and see so many things which are strikingly similar to Valentines Day 2007, a day which probably should be memorialized at MRG. In truth, it is dangerous for a prognosticator to make such analogies 4 days from the event and some key details are likely to change over the course of the next few days. With that said, there is very good agreement concerning a big noreaster this weekend, one which will provide the coast with a mix of snow, sleet, freezing rain and ice and one which will deal interior New England and much of northern New York a sizable snow event (and wind) or one that can be measured in feet. I don't want to get carried away here because it is early and hype as a tendency to fizzle. Another update in a day or two can probably zoom in on the details a little closer and we can go to work from there.
The 20th or the 21st continues to be the date of a potential pattern change with two of the three teleconnection indices turning against us. The most dominant feature according to all indications will be a big trough in the northeast Pacific Ocean and over British Columbia. The snow cover which could be fairly deep by then could mitigate any warm-up for a time. Hopefully we can also avoid any X-Mas rain drops.
Monday, December 10, 2007
Is the Airmass Clash leading to a Thursday Winter Storm Bash ??
La Nina often means some serious pain for our skiing friends south of the Mason-Dixon line and the jet stream's southeast ridge this week promises to bring another chapter of mild weather and rain to those locations. There is typically more drama concerning the impacts of the southeast ridge on Vermont and surrounding New England locations since the storm track is often lifted northward with many systems taking direct aim at General Stark and his Green Mountain companions. The arctic air provided courtesy of the negative Arctic Oscillation (AO) will take to the battlefield against La Nina's ultimate weapon (the aforementioned southeast ridge) leading hopefully to some very positive consequences as far as the upcoming weekend is concerned. I realize the drama was poured on a little thick but the Thursday storm threat is real and we should be excited to see winter storm potential such as this so early in the season.
Tuesday Teaser !!
Prior to Thursday, MRG will be impacted by what should be a rather disorganized area of precipitation late Tuesday or Tuesday night. Temperatures, particularly in the valley locations on Tuesday will warm quite significantly and in many cases may exceed the freezing mark. Precipitation in these areas may fall as a mix for a time before going to snow overnight. Aries the higher terrain, such as MRG, precipitation will be all snow and accumulations have a chance to exceed 4 inches. The snow will fall in association with a fast moving arctic cold front which will clear the areas early Wednesday and will end all precipitation by the middle to late morning. The clear skies, snow cover and light winds will set the stage for one of the colder nights of the season Wednesday night before what we hope will be some fun and games for Thursday.
Thursday's Storm !!
The fast-moving aspect of weather systems within this ambient pattern presents a challenge to the prognosticators and the Thursday's situation is no exception. The medium range guidance has been keying on a system in the southern Plains gathering moisture very quickly Wednesday night before speeding northeastward. Although it seems likely this will happen in some variety meaning the increase in clouds and the eventual accumulation of snow, the exact timing will have a big say on the end result. The usually reliable European model has been unusually unreliable for much of the fall and it seems somewhat pessimistic on moisture reaching the central and northern sections of Vermont. The GFS and Canadian model tell a different and much more appealing tale and will be one I will choose to lean to at this time. This solution has the system in question tracking from southern Illinois to southern New England. Snow would develop during the day and would fall heavily during much of the afternoon accumulating 8-16 inches as a conservative guess. Wednesday's update will have to take the more specific step on addressing accumulations and a more smaller window of start times and stop times.
The Weekend
Although this European model seems unwilling to give us any love for Thursday, it does follow up with a humdinger of a noreaster for the weekend. Unfortunately it is not good scientific practice to go buffet style as far as sifting through the model data is concerned and we will not do that here. For now we will stick to the idea that the dynamics and upper air jet stream support stemming from Thursday's storm will linger into the weekend and will keep the opportunity for new snow through Saturday when finally the commencement of a slight warming trend will act as a stabilizer for the atmosphere. Not bad though for a December 14-15 weekend !!
The Xmas week questions are beginning to role my way also. Don't want to get too distracted with that right now since I am exhausted but I will say though that the ensembles are not showing a fundamentally supportive pattern for cold and new snow beginning around the time for the winter solstice with the main axis of the upper air trough shifting in the west. In short, I am expecting a more adverse change in the pattern within a few days of the Solstice and we will have to hope that the arctic cold provided by the negative AO index can hold off such a change as long as possible. Even if the cold does relinquish significantly, we will not see a repeat of 06 when the mild weather completely depleted an already limited base.
Tuesday Teaser !!
Prior to Thursday, MRG will be impacted by what should be a rather disorganized area of precipitation late Tuesday or Tuesday night. Temperatures, particularly in the valley locations on Tuesday will warm quite significantly and in many cases may exceed the freezing mark. Precipitation in these areas may fall as a mix for a time before going to snow overnight. Aries the higher terrain, such as MRG, precipitation will be all snow and accumulations have a chance to exceed 4 inches. The snow will fall in association with a fast moving arctic cold front which will clear the areas early Wednesday and will end all precipitation by the middle to late morning. The clear skies, snow cover and light winds will set the stage for one of the colder nights of the season Wednesday night before what we hope will be some fun and games for Thursday.
Thursday's Storm !!
The fast-moving aspect of weather systems within this ambient pattern presents a challenge to the prognosticators and the Thursday's situation is no exception. The medium range guidance has been keying on a system in the southern Plains gathering moisture very quickly Wednesday night before speeding northeastward. Although it seems likely this will happen in some variety meaning the increase in clouds and the eventual accumulation of snow, the exact timing will have a big say on the end result. The usually reliable European model has been unusually unreliable for much of the fall and it seems somewhat pessimistic on moisture reaching the central and northern sections of Vermont. The GFS and Canadian model tell a different and much more appealing tale and will be one I will choose to lean to at this time. This solution has the system in question tracking from southern Illinois to southern New England. Snow would develop during the day and would fall heavily during much of the afternoon accumulating 8-16 inches as a conservative guess. Wednesday's update will have to take the more specific step on addressing accumulations and a more smaller window of start times and stop times.
The Weekend
Although this European model seems unwilling to give us any love for Thursday, it does follow up with a humdinger of a noreaster for the weekend. Unfortunately it is not good scientific practice to go buffet style as far as sifting through the model data is concerned and we will not do that here. For now we will stick to the idea that the dynamics and upper air jet stream support stemming from Thursday's storm will linger into the weekend and will keep the opportunity for new snow through Saturday when finally the commencement of a slight warming trend will act as a stabilizer for the atmosphere. Not bad though for a December 14-15 weekend !!
The Xmas week questions are beginning to role my way also. Don't want to get too distracted with that right now since I am exhausted but I will say though that the ensembles are not showing a fundamentally supportive pattern for cold and new snow beginning around the time for the winter solstice with the main axis of the upper air trough shifting in the west. In short, I am expecting a more adverse change in the pattern within a few days of the Solstice and we will have to hope that the arctic cold provided by the negative AO index can hold off such a change as long as possible. Even if the cold does relinquish significantly, we will not see a repeat of 06 when the mild weather completely depleted an already limited base.
Thursday, December 6, 2007
Mad River is off and running - Challenges lay ahead
A fiercely negative Arctic Oscillation (AO) brought some big time love to Vermont and helped give MRG one of the earliest opening day's I can remember this decade. It was also a big slap in the face to the seasonal forecast but I have no problem with that. The prospects for new snow over the next few days including the weekend do not look great as the atmosphere will become fairly stable as a ridge in the jet stream becomes established across the southeast. As I mentioned in the previous post, the southeast ridge is what La Nina does best and it forces the mountain to go on the defensive in terms of protecting its base and keeping temperatures below freezing.
Specifically for the weekend, we do have a the passing of a very benign weather system late Friday. It would obviously nice to squeeze out a few inches prior to first tracks time on Saturday but a dusting to 2 inches is the most reasonable guess I can make. Saturday's temps may approach 30 in the afternoon. On Sunday, we will be blessed with some great visibility (either clear skies or a high overcast) but low level cold will push temps to near zero in the morning while afternoon readings only approach 20.
By early next week, the baraclinic zone will be directly over Mad River Glen and much of Vermont. To put it plainly the baraclinic zone refers to the region where warm air is directly clashing with cold air thus producing a big contrast in temperatures over a relatively narrow region. It also is the region where overrrunning precipitation is often focused. The challenge involves keeping all this precipitation in the form of snow which could prove to be quite difficult. The best I can do in terms of offering out specifics now is to say that precipitation, if we get any, on Monday and Monday night will be in the form of snow. By Wednesday a much more organized area of low pressure will approach along this baraclinic area and threaten to push more warmth into central and northern Vermont. Models are suggesting that we do have a chance at keeping enough low level around to prevent a move to above freezing temperatures and plain rain. It will be tough however to keep precipitation all snow during the middle of next week. Again, we are playing defense.
By late next week and into the weekend, we are back into more widespread cold and also some instability. This means that some accumulating TIS is likely before the weekend of the 14th and 15th. There also is a chance that we are impacted by a more organized weather system. We can't really expand on that however until the next update. Enjoy the snow and the early December skiing !!!
Specifically for the weekend, we do have a the passing of a very benign weather system late Friday. It would obviously nice to squeeze out a few inches prior to first tracks time on Saturday but a dusting to 2 inches is the most reasonable guess I can make. Saturday's temps may approach 30 in the afternoon. On Sunday, we will be blessed with some great visibility (either clear skies or a high overcast) but low level cold will push temps to near zero in the morning while afternoon readings only approach 20.
By early next week, the baraclinic zone will be directly over Mad River Glen and much of Vermont. To put it plainly the baraclinic zone refers to the region where warm air is directly clashing with cold air thus producing a big contrast in temperatures over a relatively narrow region. It also is the region where overrrunning precipitation is often focused. The challenge involves keeping all this precipitation in the form of snow which could prove to be quite difficult. The best I can do in terms of offering out specifics now is to say that precipitation, if we get any, on Monday and Monday night will be in the form of snow. By Wednesday a much more organized area of low pressure will approach along this baraclinic area and threaten to push more warmth into central and northern Vermont. Models are suggesting that we do have a chance at keeping enough low level around to prevent a move to above freezing temperatures and plain rain. It will be tough however to keep precipitation all snow during the middle of next week. Again, we are playing defense.
By late next week and into the weekend, we are back into more widespread cold and also some instability. This means that some accumulating TIS is likely before the weekend of the 14th and 15th. There also is a chance that we are impacted by a more organized weather system. We can't really expand on that however until the next update. Enjoy the snow and the early December skiing !!!
Saturday, December 1, 2007
Negative AO means a strong early December start
Fundamentally, there are few allies more dependable than a negative Arctic Oscilation. Send the cold down to the mid-lattitudes and keep the relative warmth near the poles. A whole winter consisting of such a pattern and there would be no need for a single chair weather blog since every other day would be a powder day. It is encouraging to see the '07-'08 winter begin as the '06-'07 winter ended but the deck remains stacked against us unlike it was last year.
Not only do we have some cold courtesy of the AO index, but we also have a storm. One which should begin as snow late Sunday, change to a period of sleet for a time early Monday and then go back to a longer period of snow later Monday into Tuesday. Much of the snow later Monday into Tuesday will be of the terrain induced variety and I will refer to this as TIS (Terrain induced snow) for the sake of concision. It is a fairly good set-up for TIS actually and I would not be surprised to see MRG tally 10-20 inches in the period beginning late Sunday and ending early Wednesday. No sense in getting more specific with the mountain closed but if new snow totals do indeed fall in this range it could be enough to induce an opening day announcement from the powers that be.
The AO is expected to remain on the negative side of zero for the next 10 days although models are showing a dreaded strengthening of the southeast ridge by next weekend. This is going to be a tough animal to tame this winter as the prevelance of the southeast ridge is correlated to the La Nina. It will be a bullet we will need to dodge next weekend or else its mild weather and perhaps even some rain. I will check back early next week to see if MRG plans an opening and will update the blog accordingly.
Not only do we have some cold courtesy of the AO index, but we also have a storm. One which should begin as snow late Sunday, change to a period of sleet for a time early Monday and then go back to a longer period of snow later Monday into Tuesday. Much of the snow later Monday into Tuesday will be of the terrain induced variety and I will refer to this as TIS (Terrain induced snow) for the sake of concision. It is a fairly good set-up for TIS actually and I would not be surprised to see MRG tally 10-20 inches in the period beginning late Sunday and ending early Wednesday. No sense in getting more specific with the mountain closed but if new snow totals do indeed fall in this range it could be enough to induce an opening day announcement from the powers that be.
The AO is expected to remain on the negative side of zero for the next 10 days although models are showing a dreaded strengthening of the southeast ridge by next weekend. This is going to be a tough animal to tame this winter as the prevelance of the southeast ridge is correlated to the La Nina. It will be a bullet we will need to dodge next weekend or else its mild weather and perhaps even some rain. I will check back early next week to see if MRG plans an opening and will update the blog accordingly.
Sunday, November 18, 2007
Back 4 More !! – Seasonal Outlook for ’07-‘08
I always say that the approval rating of a weather guy is only as good as the weather he/she predicts. If I can’t forecast sunshine and pleasant temperatures on your wedding day then I can’t forecast my way out of a paper bag. Likewise, if I can’t predict a snowy winter for the Mad River Glen faithful then perhaps the powers that be should find someone who can ;). Don’t feel bad the sentiment is perfectly normal and I am very used to it. I am proud to be “back 4 more” or a 4th season of blog duties. It’s been a lot of fun and it’s the greatest audience. And for all those skiers who visit the blog but are still loyal to Sugarbush, Stowe or Killington; well, we are still happy to have you but would be even happier to see you buried in powder on Paradise. And for our snowboarders out there, we are happy to have you too, but I can’t provide regular updates on snowmaking, or half-pipe making in November. You will just have to get your weather from other sources until the opening bell at MRG is a few days from sounding.
If the opening sentence sounds to you like a disclaimer then your intuition is correct. There is very little to be excited about when looking at the upcoming winter from the perspective of our favorite seasonal variables. That being said, I don’t think I can do much better than 60 percent on these seasonal outlooks and I have for the most part, called the last three winters correct. This means I am overdue for a serious bust. It took one heck of a finish in 2007 to get that one into the win column but in the end the mountain tallied nearly 300 inches of snow and temperatures were slightly above normal in accordance with the pre-season prediction. There was a gentlemen (I forgot his name) who emailed me after the seasonal forecast last year and by using his favorite folklore, predicted a slow start to the winter followed by a big finish. He was even more right and should receive some well-deserved recognition.
1) ENSO – It has delivered us a low blow with the re-development of what could turn out to be a nasty La Nina.
2000-2001 quite possibly could have been the most epic winter in the history of Mad River Glen. That winter included a storm in early March which dumped 50-70 inches on much of the Green Mountain spine. Believe it or not, ENSO conditions that winter were that of a weak La Nina. 1995-1996 also featured a weak La Nina and MRG was graced with Mother Nature’s better half for much of the winter. Moderate to strong La Nina’s, such as the one threatening to prevail this winter, do not have a particularly good relationship with us MRG skiers. Some of the stronger La Nina winters include 1999-2000, 1998-1999, 1988-1989 and a string of winters during the early to middle 1970’s. Vermont typically fairs substantially better than locations further south during moderate to strong La Nina’s. Locations such as West Virginia for instance often feel the effects of a potent southeast ridge in the Jet Stream, which aside from making it incredibly mild for long stretches of the winter, also deflect storms to the north and west, which means little if any natural snow. Snow often does fall in New England but very often the snow events also include mixed precipitation or rain. We were blessed with 58 days during the second half of the 06-07-ski season without rain, an occurrence, which made last season one of my personal favorites. It is very unlikely that we will even get 30 days without rain unless La Nina subsides. Currently the critical 3&4 Nino regions are seeing SSTs of 1.3 C degrees below normal, which in a quantitative assessment is as a moderate to borderline strong La Nina. SST’s would need to warm to at least within a degree of Celsius before we can categorize the ENSO event as weak.
Round 1 - The current state of La Nina favors below normal snow and normal temperatures. A La Nina such as this one is often a knockout upper cut to the ski areas in the Middle-Atlantic but interior New England does tend to fair better but far from great.
2) Pacific Decadal Oscillation (PDO) – This is measured as an index and the October value was an ugly -1.45.
We can again start this part of the analysis on a positive note by recalling the winter of 1970-1971. This is one winter that ranks right up with 2000-2001 in the epic category and a winter where the PDO index was close to -1.70 (see link below).
http://jisao.washington.edu/pdo/PDO.latest
In general, however, there has been a correlation between the index of the PDO and the prevailing weather pattern for eastern North America and this correlation would have us hoping for a more positive index as opposed to the -1.45 recently recorded. There is some very general information on the PDO that can be obtained through Wikepedia.
http://en.wikipedia.org/wiki/Pacific_decadal_oscillation
More specific information including the page that actually tracks the indices is included here.
http://jisao.washington.edu/pdo/
Both the index of the PDO and the ENSO have been known to change quite abruptly even at the 11th hour. It is often why many seasonal forecasts which are made too early in the autumn go belly up. This seasonal outlook has been created fairly late in the ball game but these variables still have some time to do some shifting. Unless they do however I think we are in trouble.
Round 2 – The current negative index of the PDO favors both below normal snow and above normal temperatures.
3) Snow cover area – One of my favorite seasonal indicators when looked at hemispherically. When measured in millions of square KM the normal snow cover area in October is 17.7. Last year we recorded an October number of 19.8 but this year its closer to 16.3. Yuck !!
The measure of a winter from the standpoint of temperature is usually determined by the following tongue twister. The strength of the cold embedded within the cold pattern. The “strength of the cold” refers to the arctic air originating near the poles. Arctic air of a stronger intensity in a fundamentally colder than normal pattern may mean the difference between 5 degrees and 15 degrees below normal. Likewise, a normal pattern may be 5 degrees below normal instead of 5 degrees above and the adverse impacts of an above normal pattern may very well be significantly mitigated. The opposite if of course true if the air with polar origins is weaker than expected. It is important to examine this issue in any seasonal outlook because the most basic assumption that needs to be made is that the winter will consist of both fundamentally mild or unfavorable patterns for us MRG skiers and fundamentally cold or favorable patterns. 2006-2007 was a winter where us New Englanders got a good look at both sides of the spectrum.
So what does snow cover in October indicate about the measure of cold in an upcoming winter? It has to do with cold pooling efficiency. A greater coverage of snow in the polar regions early in the year will allow arctic air to strengthen quicker and reach a greater maximum intensity. An analogy can be drawn between the effects of snow cover on arctic air and the effects of anomalously warm water has on hurricanes. 2005, the year which featured Hurricane Katrina among many other land-falling storms, was defined by warmer than average water temperatures in the Caribbean and Gulf of Mexico. Storms traveling through these areas strengthened quicker and reached a greater maximum intensity. Arctic air has a similar relationship with snow cover.
Round 3 - 16.3 millions of square km is a very ugly number snow cover number. It is worse in fact than what we saw in the autumn months of 2001 and in 2005, which preceded two not-so-friendly winters. To put it mildly, the data favors above normal temperatures and when combined with some of the aforementioned indicators, I would be very surprised to see temperatures average below normal for the December to March period.
The Prediction – No spin here at the Single Chair Weather Blog. We tell it like it is though admittedly I am hoping to be dead wrong. Temperatures for the season will average above normal and significantly so. When I say significant I mean at least 3 degrees above normal for the December through March period. In terms of snow, I predicted 300 inches last year against an average of 260. This year I expect less than 220. Sorry for the lack of hype but I always like to say, if you keep expectations at a minimum you open the floor for a few pleasant surprises.
If the opening sentence sounds to you like a disclaimer then your intuition is correct. There is very little to be excited about when looking at the upcoming winter from the perspective of our favorite seasonal variables. That being said, I don’t think I can do much better than 60 percent on these seasonal outlooks and I have for the most part, called the last three winters correct. This means I am overdue for a serious bust. It took one heck of a finish in 2007 to get that one into the win column but in the end the mountain tallied nearly 300 inches of snow and temperatures were slightly above normal in accordance with the pre-season prediction. There was a gentlemen (I forgot his name) who emailed me after the seasonal forecast last year and by using his favorite folklore, predicted a slow start to the winter followed by a big finish. He was even more right and should receive some well-deserved recognition.
1) ENSO – It has delivered us a low blow with the re-development of what could turn out to be a nasty La Nina.
2000-2001 quite possibly could have been the most epic winter in the history of Mad River Glen. That winter included a storm in early March which dumped 50-70 inches on much of the Green Mountain spine. Believe it or not, ENSO conditions that winter were that of a weak La Nina. 1995-1996 also featured a weak La Nina and MRG was graced with Mother Nature’s better half for much of the winter. Moderate to strong La Nina’s, such as the one threatening to prevail this winter, do not have a particularly good relationship with us MRG skiers. Some of the stronger La Nina winters include 1999-2000, 1998-1999, 1988-1989 and a string of winters during the early to middle 1970’s. Vermont typically fairs substantially better than locations further south during moderate to strong La Nina’s. Locations such as West Virginia for instance often feel the effects of a potent southeast ridge in the Jet Stream, which aside from making it incredibly mild for long stretches of the winter, also deflect storms to the north and west, which means little if any natural snow. Snow often does fall in New England but very often the snow events also include mixed precipitation or rain. We were blessed with 58 days during the second half of the 06-07-ski season without rain, an occurrence, which made last season one of my personal favorites. It is very unlikely that we will even get 30 days without rain unless La Nina subsides. Currently the critical 3&4 Nino regions are seeing SSTs of 1.3 C degrees below normal, which in a quantitative assessment is as a moderate to borderline strong La Nina. SST’s would need to warm to at least within a degree of Celsius before we can categorize the ENSO event as weak.
Round 1 - The current state of La Nina favors below normal snow and normal temperatures. A La Nina such as this one is often a knockout upper cut to the ski areas in the Middle-Atlantic but interior New England does tend to fair better but far from great.
2) Pacific Decadal Oscillation (PDO) – This is measured as an index and the October value was an ugly -1.45.
We can again start this part of the analysis on a positive note by recalling the winter of 1970-1971. This is one winter that ranks right up with 2000-2001 in the epic category and a winter where the PDO index was close to -1.70 (see link below).
http://jisao.washington.edu/pdo/PDO.latest
In general, however, there has been a correlation between the index of the PDO and the prevailing weather pattern for eastern North America and this correlation would have us hoping for a more positive index as opposed to the -1.45 recently recorded. There is some very general information on the PDO that can be obtained through Wikepedia.
http://en.wikipedia.org/wiki/Pacific_decadal_oscillation
More specific information including the page that actually tracks the indices is included here.
http://jisao.washington.edu/pdo/
Both the index of the PDO and the ENSO have been known to change quite abruptly even at the 11th hour. It is often why many seasonal forecasts which are made too early in the autumn go belly up. This seasonal outlook has been created fairly late in the ball game but these variables still have some time to do some shifting. Unless they do however I think we are in trouble.
Round 2 – The current negative index of the PDO favors both below normal snow and above normal temperatures.
3) Snow cover area – One of my favorite seasonal indicators when looked at hemispherically. When measured in millions of square KM the normal snow cover area in October is 17.7. Last year we recorded an October number of 19.8 but this year its closer to 16.3. Yuck !!
The measure of a winter from the standpoint of temperature is usually determined by the following tongue twister. The strength of the cold embedded within the cold pattern. The “strength of the cold” refers to the arctic air originating near the poles. Arctic air of a stronger intensity in a fundamentally colder than normal pattern may mean the difference between 5 degrees and 15 degrees below normal. Likewise, a normal pattern may be 5 degrees below normal instead of 5 degrees above and the adverse impacts of an above normal pattern may very well be significantly mitigated. The opposite if of course true if the air with polar origins is weaker than expected. It is important to examine this issue in any seasonal outlook because the most basic assumption that needs to be made is that the winter will consist of both fundamentally mild or unfavorable patterns for us MRG skiers and fundamentally cold or favorable patterns. 2006-2007 was a winter where us New Englanders got a good look at both sides of the spectrum.
So what does snow cover in October indicate about the measure of cold in an upcoming winter? It has to do with cold pooling efficiency. A greater coverage of snow in the polar regions early in the year will allow arctic air to strengthen quicker and reach a greater maximum intensity. An analogy can be drawn between the effects of snow cover on arctic air and the effects of anomalously warm water has on hurricanes. 2005, the year which featured Hurricane Katrina among many other land-falling storms, was defined by warmer than average water temperatures in the Caribbean and Gulf of Mexico. Storms traveling through these areas strengthened quicker and reached a greater maximum intensity. Arctic air has a similar relationship with snow cover.
Round 3 - 16.3 millions of square km is a very ugly number snow cover number. It is worse in fact than what we saw in the autumn months of 2001 and in 2005, which preceded two not-so-friendly winters. To put it mildly, the data favors above normal temperatures and when combined with some of the aforementioned indicators, I would be very surprised to see temperatures average below normal for the December to March period.
The Prediction – No spin here at the Single Chair Weather Blog. We tell it like it is though admittedly I am hoping to be dead wrong. Temperatures for the season will average above normal and significantly so. When I say significant I mean at least 3 degrees above normal for the December through March period. In terms of snow, I predicted 300 inches last year against an average of 260. This year I expect less than 220. Sorry for the lack of hype but I always like to say, if you keep expectations at a minimum you open the floor for a few pleasant surprises.
Thursday, April 5, 2007
Winter returns and will give MRG a true Easter grand finale !!!
And a grand finale it will be for both the mountain and for the 06-07 edition of the Single Chair Weather Blog. Sorry for the less than frequent updating but the uncertain status of the mountain gives little incentive for continuous updates (although the weather has provided incentive enough). The general themes from the update a week ago were very much on the ball although I freely admit that it was almost shocking to see snow fall through much of the day yesterday when a few days prior it looked like a 45 degree rain was almost certain. Thus the forecast for this past Wednesday was first class bust. This is another example of how the war between warm vs cold and rain vs snow is fought on different battle lines every year with different coefficients and different variable inputs. In a final analysis, the cold and snow has won many victories in 2007 compared to the few if any won in 2006.
Cold in April can mean big things for the New England high country
The skinny on the weekend is for winter-like cold and terrain induced snow which will continue sporadically through early next week when at that point the seasonal snowfall will be very close to average thus finishing off our incredible 2007 comeback. For a minute here let me just rave about what can be accomplished when cold weather combined with deep upper trough settles favorably over Vermont in April. Instability just thrives in April and the reason is this. The sun angle is obviously higher providing more hours of daylight and more time to warm the earth's surface. The middle and upper level layers of the atmosphere are slower to respond to the seasonal changes and thus we have a climatologically more unstable period (warmer at the surface, colder aloft) in the spring and a likewise more stable climatological period in the fall. It is the same concept behind the severe weather season in the plains when tornadoes are the most frequent and most destructive. It may sound confusing and thats because like many things in life it is a relative game.
1-2 additional feet and a few powder days
So with that little tangent fully exercised I can continue with a forecast. It must be prefaced however the rapidly becoming famous "subject to bust" disclaimer which should automatically apply to terrain induced snow events since they are so tricky to predict accurately. With the cold weather now becoming firmly entrenched the big question now becomes when and how much terrain induced snow will fall. I looked at as many things as I could Thursday morning and decided that the snow should fall heaviest Thursday (the time of this update) and Thursday night and then again beginning late Saturday through Sunday and Monday. The period beginning Friday and ending early Saturday appears to be the time frame where the region will be in between the two jet amplifications. I think this translates to a forecast where heavier snow showers Thursday and Thursday night taper to flurries Friday, Friday Night and early Saturday before snow showers re-intensify later Saturday and persist through Sunday, Sunday night and even Monday. Yikes ! Say that 3 times fast ! The powder days, and they will be powder days by the way given the intensity of this very impressive April cold, given this forecast will be Friday, Sunday and Monday. Snowfall has already totaled close to 10 inches as of midday Thursday and I am conservatively expecting an additional 1-2 feet by late Monday. 6-12 of these inches may very well fall by first tracks time on Friday.
If we can convince the powers that be at MRG to stay open later than Easter Sunday, there could another big easter egg discovery courtesy of mother nature. It is a bit early and medium range computer models are not exactly aligned as of yet but the possibility of a mid to late week storm exists producing snowfall of the more synoptic (as opposed to the fluffy terrain) variety.
With that I will sign off for the season. If your heading out this weekend dress warm. The forecast may say 30's for the valley locations but temps will be substantially colder on the mountain (20's). Thanks to all the readers for the interest in both the blog and skiing at MRG. We will ramp it up again for another season late this upcoming fall. Until then, enjoy the remainder of spring and upcoming summer.
-Joshua Fox
Single Chair Weather Blog
Cold in April can mean big things for the New England high country
The skinny on the weekend is for winter-like cold and terrain induced snow which will continue sporadically through early next week when at that point the seasonal snowfall will be very close to average thus finishing off our incredible 2007 comeback. For a minute here let me just rave about what can be accomplished when cold weather combined with deep upper trough settles favorably over Vermont in April. Instability just thrives in April and the reason is this. The sun angle is obviously higher providing more hours of daylight and more time to warm the earth's surface. The middle and upper level layers of the atmosphere are slower to respond to the seasonal changes and thus we have a climatologically more unstable period (warmer at the surface, colder aloft) in the spring and a likewise more stable climatological period in the fall. It is the same concept behind the severe weather season in the plains when tornadoes are the most frequent and most destructive. It may sound confusing and thats because like many things in life it is a relative game.
1-2 additional feet and a few powder days
So with that little tangent fully exercised I can continue with a forecast. It must be prefaced however the rapidly becoming famous "subject to bust" disclaimer which should automatically apply to terrain induced snow events since they are so tricky to predict accurately. With the cold weather now becoming firmly entrenched the big question now becomes when and how much terrain induced snow will fall. I looked at as many things as I could Thursday morning and decided that the snow should fall heaviest Thursday (the time of this update) and Thursday night and then again beginning late Saturday through Sunday and Monday. The period beginning Friday and ending early Saturday appears to be the time frame where the region will be in between the two jet amplifications. I think this translates to a forecast where heavier snow showers Thursday and Thursday night taper to flurries Friday, Friday Night and early Saturday before snow showers re-intensify later Saturday and persist through Sunday, Sunday night and even Monday. Yikes ! Say that 3 times fast ! The powder days, and they will be powder days by the way given the intensity of this very impressive April cold, given this forecast will be Friday, Sunday and Monday. Snowfall has already totaled close to 10 inches as of midday Thursday and I am conservatively expecting an additional 1-2 feet by late Monday. 6-12 of these inches may very well fall by first tracks time on Friday.
If we can convince the powers that be at MRG to stay open later than Easter Sunday, there could another big easter egg discovery courtesy of mother nature. It is a bit early and medium range computer models are not exactly aligned as of yet but the possibility of a mid to late week storm exists producing snowfall of the more synoptic (as opposed to the fluffy terrain) variety.
With that I will sign off for the season. If your heading out this weekend dress warm. The forecast may say 30's for the valley locations but temps will be substantially colder on the mountain (20's). Thanks to all the readers for the interest in both the blog and skiing at MRG. We will ramp it up again for another season late this upcoming fall. Until then, enjoy the remainder of spring and upcoming summer.
-Joshua Fox
Single Chair Weather Blog
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