It's coming

We have flurries to hand out, a winter to recap, and some other sundries. This weekend is planned as a weekend to catch up on the Tubes. So stay tuned.

That was the winter that was—mid-season report

I'd say this is the TW3 report, but the tenses would be wrong, since we're really only about half way through. So, maybe I'll call it TITWTI (this is the winter that is), or something. In any case, it's about time to examine where we stand compared to recent winters, look at some condition reports, and prognosticate where we might wind up, as well as spill some fun weather data. And, yes, there's a darned good reason I did the season recaps after the snow had melted last March: time! So this may be rather short and periodically updated.

Now, we know that ski conditions are, uh, pretty awesome. It got a late start, but since then there has been continuous skiing, with only a couple days without at least good conditions. (Ski conditions were discussed at length last year here.)

So, where do we stand? Well, first of all, we're at, as of February 10, 65 days of skiing, of which 61 have been good or excellent. We have not had to contend with the "oh no will it melt" syndrome which has plagued some past ski seasons, and the base is now up to 15 inches, the highest in nine years, with no meltdowns in sight. The City of Lakes went off without a hitch, Mora will as well, and Birkie has two feet of base two weeks before the race. As long as we can make March 15, we'll have 100 days of skiing, and an "excellent" snow year.

What's interesting is that despite the great skiing since early December (even after a couple of minor meltdowns the trails have, for the most part, been resurrected) it has not been a particularly cold or snowy winter. December was about a degree below normal, January, despite a cold start, finished just a tenth below. Snowfall through the end of January was 26.8 inches, of which 20.9 fell in December (2.8 in October, 0 in November, just 3.1 in January). With 11.3 inches so far in February, we're up to around normal. So it's been a very normal winter.

Despite some variability and unusual storms, there have been no real extremes. We've had no brutal cold snaps (no day has stayed below 0) but also no major warm-ups. The latter is, I think, the reason that we've kept our base so well. If you look back at the past few years, every one has a pretty devastating warm-up. Last January 31 it skied to 45 degrees, a week later it was 47. January '08 hit 40 twice (December '07 had as well), 2007 was, well, let's not talk about it, and other years were similar. It got me to thinking: we haven't been above 40 for more than 70 days. What are the records days under x degrees? I delved in to the data to find out.

	Longest		Second longest		Third longest
Temperature	Days	Ending:	Days	Ending:	Days	Ending:
0	7	Jan 7 1912	6	Jan 28 1904	5	Four times
5	12	Jan 12 1912	10	Jan 27 1963	9	Jan 27 1936
10	21	Feb 7 1936	15	Jan 1912/1974	13	Feb 21 1936
15	36	Feb 21 1936	16	Jan 1912/1977	15	Jan 12 1974
20	39	Feb 22 1936	25	Feb 15 1905	24	Feb 12 1904
25	41	Feb 22 1936	32	Feb 8 1978	27	Three times
27	52	Feb 19 1979	47	Feb 9 1912	41	Feb 22 1936
29	52	Feb 19 1979	50	Feb 12 1912	47	Feb 22 1978
30	58	Feb 19 1979	52	Feb 12 1912	48	Feb 25 1939
31	66	Feb 22 1978	58	Feb 19 1979	52	Feb 13 1912
32	66	Feb 22 1978	58	Feb 19 1979	52	Feb 13 1912
33	67	Feb 23 1978	58	Feb 19 1979	53	Feb 13 1912
34	67	Feb 23 1978	60	Feb 21 1979	54	Feb 13 1912
35	71	Feb 21 1969	70	Feb 22 1936	69	Feb 15 1971
36	79	Mar 7 1940	77	Feb 22 1936	75	Mar 15 1975
37	106	Mar 6 1972	84	Feb 13 1943	81	March 9 1978
38	116	Mar 12 1979	106	Mar 4 1972	105	Mar 1904/1955
39	122	Mar 22 1904	116	Mar 12 1979	114	Mar 2 2001
40	122	Mar 22 1904	116	Mar 12 1979	114	Mar 2 2001
42	126	Mar 13 2001	125	Mar 24 2006	122	Three times
45	141	Apr 3 1979	140	Apr 12 1975	135	Mar 24 1956
50	152	Apr 11 1979	149	Three times	148	Several times

Some of these data are pretty amazing. 66 days at or below freezing in 1977-8 is probably the best known. But go a couple degrees warmer, and you get 106 days at or below 37 degrees in 1972, which is, perhaps, just as impressive: it was below 37 from November 21 to March 6! And our last big snow year—the last time Minneapolis banned parking outright on one side of the street. Right now, we have a good chance of overtaking third place for the 37 degree mark, as we are just ten days away (and two weeks out of second). But there have been some impressively long cold streaks in the past. This current streak is long, and cold, but not really historic. Yet.

2009 Ski Season Awards!

It's that time of year again. Well, not again. The snow has melted, the sun is out (hooray!) and most of us are focusing in on running, biking, when the trails will dry out, when we actually want to start rollerskiing, how quickly we can make up for the beer we didn't drink during the ski season, &c.

But it's also time for the First Annual SkiMSP Blog Awards:

"The Flurries"

That's right, this blog will give out awards over the next week in several categories, with the winners determined completely unscientifically and solely by me. The winners of these prestigious awards will go on to fame and fortune. Or not. Awards will be given in the following categories:

* Website of the year: for the website which has done the most to advance local skiing.
* Skier of the year (male and female): for the local skiers who have had the most impressive skiing years (and a premium is placed on both local, national and international racing).
* Race of the year: for the race with the best snow, volunteers and organisation
* Volunteers of the year: this will be given only in years when a group of volunteers, through superhuman effort, advances the interests of skiers or makes a race happen despite all odds (see Loppet, City of lakes, 2006).
* Snowmaking of the year: for the best fake snow in the area
* Striding tracks of the year: for the best striding tracks in the area
* Grooming of the year: taking in to account snow conditions and amount, dedication and general vigour, verve and alacrity, which trail has the best grooming of the year
* Trail of the year: all things considered (grooming, terrain, snow &c.) the best trail of the year.

Again, this is all based on my opinions. If you disagree, leave a comment and start a flame war!

That was the season that was—SKIING

In our last post, we discussed criteria for rating different winters. This was all based on skiable days, and the quality of the days, and such.

So how did this season stack up, and how does it compare to other seasons? Let's chart this out:

	Skiable Days		Races			Days in			Murphy
Year	Total	G/E	COLL	Mora	Birkie	Dec	Jan	Feb	months	Rating
2008-9	93	75	Full	Full	Full	28	31	18	4	Good
2007-8	123	90	Full	Cold	Full	31	31	29	4	Excellent
2006-7	78	33	Full	Lake	Short	1	31	26	2	Fair
2005-6	107	40	Full	Full	Full	31	29	27	3	Good
2004-5	42	7	Cancel	Full	Full	0	20	14	0	Poor
2003-4	103	45	Full	Full	Full	23	31	28	2	Good
2002-3	40	17	Lake	Lake	Full	0	0	26	1	Poor

* G/E = good/excellent

That seems about right. And if it seems like we've been a bit spoiled this year and last, we have. From 2002-3 to 2006-7, there were a total of 142 "good or excellent" snow days each year. That's an average of less than 30. However, in the last two years, there have been 165 "good or excellent" days, averaging nearly three months, and more than the previous five years combined. That's not too shabby (although snow between Mora and Birkie would have been nice).

But if we want to go a bit further, we can look at each season, day by day. To view a larger version of these charts, click on them. The key is:

* White = a day without local skiing
* Light Blue = a day with fair or poor skiing locally
* Dark Blue = a day with good or excellent skiing locally
(The gray bars are in place on February 29 on non-leap years.)

And for each race, green denotes a full race, yellow a partially-skied race (either on a lake or shortened, although since this concerns mainly snow quality, a race shortened or canceled due to cold is still counted as a full race) and red a canceled race.


To see everything at once, without a lot of scrolling, I've broken the last seven years in to two:


Now, why does this only go for back seven years? Well, that's as far back as Skinnyski's archives go. I'd be glad to build more in to my little database if the information is of high enough quality, but I fear that pre-2002 reports, if they exist, might not exist in a high enough number to be of much use. What with the Internet being a lot less widespread back then. I may build something based on weather and snow depth, but it would be even more rudimentary.

But if we look back over the last seven years, what is the best date for skiing. If you want to have an event on a certain date, and that depends on snow, what is the best day you can pick? The answer is February 9. Out of a total possible 14 points (one awarded for a day having snow, another added if it was "good" or "excellent" conditions), February 9 garners 12. Other than the horrid winter of 2004-5 (the City of Lakes meltdown), it had good or excellent conditions every year. Disregarding condition, are there any days which had skiing every day in the last seven years? Well, actually, yes, several, all in February (mainly because there wasn't snow until February 1, 2003). They are the 3d, 14th, 15th, 21st and the 24th to 27th. Again, we can chart this out, using the same type of key:



What might this tell us? Well, based on a very small data set, there is some sort of skiing 5/7 of the time from January 1 to March 14. As far as good days, January and early February are pretty good, as is late February and March. There's a bit of a lull in between. Of course, this is most assuredly a statistically insignificant sample, but perhaps there are two peaks to winter, and the dreaded January Thaw is not mythical. We'll see how the numbers stack up in to the future.

That was the winter that was—how to quantify ski conditions

Recently, we explored the weather of the now-seemingly-over winter of 2008-2009. Today, we'll look in to how the skiing went, and how it measures up against recent years. With the weather, it was rather easy. First of all, there are numbers. There's data going back nearly two centuries. So it's not very qualitative. Second of all, some folks have done a lot of work documenting the weather. Ski conditions, on the other hand, are a little harder to quantify. We'll set up the qualifications for different levels of ski season quality (excellent, good, fair, poor) today, and explore the current season, and recent past seasons, later this week.

One way to do this is to count skiable days. But where do you count them, and how? Do you count days you could ski on the Como Glacier (quite a few—it probably still has snow on it)? Or days you could use your best skis at Murphy (not quite as many days, but it is a bit more fun)? And if we are going to rate ski seasons (as I am about to attempt to do), we need to establish some sort of criteria. We'll figure out how to decide whether it is an excellent, good, fair or poor season for skiing. So, what makes a good snow year?

Well, jumping beyond trail conditions at large, we can focus on three trails at three times: The City of Lakes Loppet Course (when it is held), the Mora Vasaloppet course when it is held, and the Birkie. These are entirely subjective: three points in time in three disparate locations. They do, however, account for the three largest long races anywhere near the Twin Cities. In addition, they are the only local (under three hours drive) snow-on-the-street finishes—with cheering crowds lining the course. They occur from late January to late February, generally the peak of most local racing (although there are many fine races earlier on), and when we really want snow on the ground. I'd be hard pressed to call it a "good snow year" if one (or more) of these events is shortened, "laked" or canceled. Plus, they traverse a diverse set of terrain, and they are usually rather indicative of local trail conditions.

Thus, these races will be used to assess ski seasons as follows:
• For a ski season to be excellent, all races must be held in their entirety (with the minor exception that the City of Lakes may be shortened by a couple kilometers since it is the furthest south of any major races and most prone to melting—if a couple k on the front nine are shaved off, it still qualifies).
• For a good snow year, at least two races must be fully held, and the third can not be canceled, it can only be shortened (due to snow, not cold temperatures, which do not represent the snow conditons) or "laked."
• If more than one event is shortened, or one is canceled, a season can be ranked only as high as fair, and
• If all three are shortened, or more than one is canceled, only a poor rating for the season will suffice.

Beyond the races, we begin to analyse snow conditions. When we looked at the year in weather, we looked some at snow depth. But ski conditions are based not only on snow depth, but on the temperature (ice, slush, &c.) and, of course, on grooming. What good is six inches of snow pack if it is topped with an impenetrable layer of glare ice? And what of the differences across the area? Sometimes there's good skiing at Murphy and Lebanon with brown grass at Elm Creek and Elk River. Sometimes Woodland Trails have good conditions and everyone else is on man-made snow. At times the whole Metro is very white, but only some areas have good enough grooming to merit good conditions. Wouldn't it be nice if there were a treasure trove of ski trail observations from across the Twin Cities going back several years?

Of course, I am referring to Skinnyski.com's "First Hand Trail Reports." Thanks to Bruce and his archiving, we can go back towards the start of the internet and compare conditions across the area each day of the winter—from the first "fast grass" to the last melting slush at Woodland Trails. For the purposes of this analysis, the "Metro" will stretch across the seven county region, and poke in to Sherburne to include the trails in Elk River, which often prolong the local ski season on their own.

Now, how do we count skiable days? Well, based on the reports on Skinnyski, I've devised two levels of skiing. One is "poor to fair." For a day to be counted under this criterion, somewhere in the Metro (other than a lake or manmade snow) needs to be at least somewhat skiable. This can include "fast grass" or crust skiing, but somewhere there must be the ability that day to strap on a pair of rock skis and glide. That is counted as a poor-to-fair day. The other criterion is "good to excellent." For this to be in play, somewhere between Murphy and Elk River needs to be skiable with good skis (excellent or very good) or at least two locations need to be reporting "good" conditions—skiable on at least "B" skis. If these criteria are not met, it is counted as a fair-to-poor day.

Once the days are counted, we can quantify a season:
• An "excellent" season must have at least 100 days of skiing, with at least 75 "good to excellent"
• A "good" season must have at least 75 days of skiing, with at least 50 "good to excellent." If a season has more than 100 days of skiing, only 40 need to be "good to excelent"
• A "fair" season requires at least 50 days of skiing, with at least 35 rated "good to excellent." A season with 20-30 days of "good to excellent" skiing can qualify for fair if it had at least 75 days of skiing overall.
• If a season does not meet any of these criteria, it is rated as a "poor" ski season.

Since this is already quite subjective, I'll throw in a few more criteria:
• For a season to be rated "excellent" there must be at least 20 days of skiing in December, January and February. March skiing is great, but it's not the same when the skiing is after all the races.
• For a season to be rated "good" there must be at least 20 days of skiing in at least two of the months of December, January and February.
• For a season to be rated "excellent," Murphy-Hanrahan, the most notorious of the "needs a lot of snow to open" venues, must be open and "good to excellent" in at least three separate calendar months. For a "good" season, two are required.
• No season may be rated "good" or higher unless there was at least ten days of skiing before January 1. What good is late snow when you are rollerskiing on Christmas?
• No season may be rated as "excellent" when a major race (such as the Bear Chase, the Noque, the Pepsi, the Gov Cup, any major Birkie Trail event, the Minnesota High School Championships, Nationals or JOs, if they are held in the Upper Midwest, &c.) is canceled due to lack of snow. If two are canceled, a season will not be rated "good."

Finally, ski seasons will be rated at a certain level only if all of the criteria for that level are met. Later this week we'll rate this season, and past seasons back to 2002-2003, with some nifty charts as well.

That was the winter that was—weather

In the space of about 36 hours last week, we went from -4 to 50, and two days later we were close to 70. It melted all the snow this side of Duluth, it seems, and, looking at the weather charts for the next couple weeks to April (have we skied in April? Yeah, but it melts real quick), has pretty much put an end to the ski season. Today, I'll tackle the numbers, later I'll look at the ski season.

So how did it stack up? How does it compare to last year, and previous years. Was it warmer or colder? Was the snow better or worse? How was the skiing and grooming?

Well, there are a lot of ways to answer. First, we can look at the temperatures and snow (skiing will come later). "Meteorological Winter" runs from December to February—for which records are kept. March counts as spring. This coincides rather nicely with local ski season—there are some races in March but the big ones are done and the races are generally up north. Here's how it looks:

Month	Avg. High	Avg. Low	Mean	Max	Min	Hi >32	Lo <0
Dec.	23	4	13.5 (-5.2)	41	-13	6	12
Jan.	16.8	-0.2	8.3 (-4.8)	46	-22	1	15
Feb.	29.1	12.4	20.8 (+0.7)	47	-5	13	4

A few more tidbits: snowfall was about normal (17, 8 and 11 inches) as were below zero temperatures—about 30 for the winter. There were ten days below -10, and two below -20, the first time in five years. We had a month below freezing (December 30-January 30) and almost a calendar month until the temperature skied to 46 on the afternoon of the last day of January. We were running about five degrees colder than normal, February was about average.

The coldest day of the winter was January 15, which actually fell midweek and not during a race—what are the chances. Up north was down near -40; at the airport the high was -6, the low -22, meaning for the day it was 25 degrees below average. A lot of the 'burbs went to -30 or colder. March 11, however, with a high of 8 and a low of -3, was 27 degrees below average. The warmest day, and the only day not to fall below freezing, was during the mid-February, snow-eating meltdown when the high was 47 and low was 35, 23 degrees above normal. That was a bummer—at least it was post-Mora and post-City of Lakes and Birkie was pretty much spared.

Now, on to the meteorological, numerological and chartological fun. A guy called Charles Fisk has a great website chronicling Twin Cities weather back to the '20s. The 1820s. I'm not going to link his whole site—though I could—but he has taken a ton of data and presented it in great charts. For instance, here's the month of January, in temperature.

But then it gets cool. For this winter he has charted snowfall, against the average snowfall. It'll make more sense with a chart:
Okay, that's pretty cool. And he has charts going back to 1884 (for snow), for the year, with snowfall, snow depth, temperature and all else. Here's 2008, for example. And then he has some outrageously awesome charts, like this one, showing average temperature over the whole year, by hour. Uh, amazing? I could spend all day at this site.
No wonder I love early may—60s and dry. If that's not cool enough, he has charts about wind speeds and directions and even thunderstorm probabilities (most frequent just before dawn in July fwiw).

Anyway, what can we deduce from all this information? Well, it was a pretty normal winter. It was a little colder early on, and then normalised some. The snow never got deep, but it's not terribly frequent to have deep snow in the Twin Cities. Look at the average snow depths by day for Minneapolis. The median from Mid-January to Mid-February is about five inches of depth—which is about what we had this winter. And before New Years it is significantly less. So, I got to thinking, when did we build a real "base" of snow? When did we have a good, deep layer of snow on the ground—a foot or more—in January or February. It seems abnormal not to have it, although it is actually an aberration. The last time the snow depth was more than a foot in January or February for more than a couple days was in 2001, a good snow year; and before that 1997. Before that, you have to go back to even years in the early '08s: 1986, 1984 and 1982. Before that were six years from 1969, '70, '71 and '72, 1975 and 1979. Before that, it happened one other time in each the 1960s, 1950s, 1940s, and 1930s. So people remembering the big winters remember a seventeen year period from 1969 to 1986—since the advent of skating there have been two winters with real "base building."

What I mean by base building, is snow maps like (and these are from the Minnesota Climate Working Group at the U, going back to the mid-90s):
That's March 1, 2001. Most of Minnesota had had a foot of snow or more on the ground for a month, and more than 18 inches at the end of the month. I wasn't around, but that looks awesome. The best we mustered this year was mid-January, when most of the state had a foot. Not too shabby.

A couple more data points: A nice article from skinnyski.com (PDF) shows that the 1960s to 1980s were higher than average in snowfall but that we actually seem to be getting a bit more snow compared to the first half of the century(see pages six and seven). From Fisk's site, again comes:
(click to enlarge). Again, it shows the heyday of snow in the Twin Cities from about 1970-1985, but also it looks like snowfall has been increasing slightly. Does this mean the snow sticks around more? No, likely not—warming temperatures may preclude that, but they may well cancel each other out.

And, we might well be due for a nice, good winter with a foot and a half of snow on the ground where one warm spell doesn't kill the snow, as they seem to come once a decade or so (save for the '70s and '80s). Of course, we have snow-making now (and Wirth will probably get better at, you know, making enough snow) which helps, too. We paid dearly from 2001 to 2007—we'll explore that soon—but have done rather well this year and last, and hopefully will do better going forwards.

And stay tuned for a rough analysis, using Skinnyski.com trail reports, of conditions for every day back to 2002 (when Bruce's site started archiving).

(Oh, and take this all with a grain of salt. Despite some weather geekiness, IANAM—I am not a meteorologist.)