Late Season Snowfall in Minnesota

photo by Nic McPhee via Flickr
photo by Nic McPhee via Flickr

A week ago today, the landscape in southern Minnesota was snowless. Our lawn was bare – covered only with brown grass (which I convinced myself was most definitely turning green by the hour) and the desiccated leaves of last autumn. I imagined myself getting to work in the garden, planting hardy seeds of kale and spinach. I threw the kids’ snowsuits down the stairs to wash and dry them to put in storage for next fall. As retribution for such thoughts and actions, we received 3.6 inches of snow on Sunday night and more is coming down even as I type. After nearly 30 years here, you’d think I would know better. In Minnesota, you must keep your dreams of spring in check until at least April, possibly May.

In the Twin Cities, the average snowfall for March is 10.2 inches, beating out all months besides December and January. In March of 1951, the Twin Cities received a whopping 40 inches of snow. (Tangent: They shoveled this by hand. No ‘snowblowing’. Although snow throwing machines were invented as early as the 1880s for clearing train tracks, the domestic use ‘walk behind’ machines were only just coming on the market in the early 1950s.) Calling March ‘spring’ here might be tempting fate. March is a month of extreme variability in Minnesota with a record high of 88°F and a record low of -50°F. That’s a 138 degree spread!

I’ve been reading meteorologist Mark Seeley’s informative Minnesota Weather Almanac this week. In this book, Seeley details Minnesota’s worst and most remarkable winter storms. I was surprised how many of them occurred in March. My surprise is probably due to my annual (and naive) belief that winter is over in March – a belief which is perpetually crushed. Do I learn? Of course not, I’m an optimist; we never do.

A few notable late season snow storms:

March 19-20, 1826: Like 1951, March of 1826 brought about 40 inches of snow, including 18 inches on these two days causing snowdrifts of 6 to 15 feet. This snowfall was followed by a further 8 inches in early April. Subsequently, a blast of cold air (4°F on April 10th) arrived further delaying the breakup of ice on the rivers. This sequence of events led to massive flooding carrying away low lying buildings at Fort Snelling and Fort Crawford as well as Chief Little Crow’s village at the site of modern day South Saint Paul. The river ultimately crested at 20 feet above low water.

April 5, 1933: A heavy snowfall struck the north shore, dumping 28 inches of snow in Cook County, a still standing record for 24 hour snowfall in April.

March 15-16, 1941: A blizzard hits western Minnesota. 85 mph winds were reported at Grand Forks and 75 mph winds were reported at Fargo-Moorhead. The wind chill bottomed out at -35°F. Although snowfall from this storm was light, a number of people died from exposure due to the extreme winds and temperatures. Before this storm, Minnesota only had observational weather services, but upset over the lack of warning and the resulting fatalities resulted in forecasting services being added by the National Weather Services.

May 2-3. 1954: Yes, you read that correctly, MAY. A huge storm moves across northern Minnesota. Dropping as much as 10-12 inches of snow across much of the northern half of the state. I would be pissed.

March 14-15, 2002: A storm of mixed precipitation, thunder, and lightning, brought 10-21 inches of snow.

March and April snowfalls aren’t the outliers I’d like the believe they are. They are, in fact, the norm. And while they are often minor interludes between luxuriously (to Minnesotans) sunny days in the mid-40s, they can also be severe, even dangerous. Huge winter storms can even arrive in May (as they did in 1954), but it’s uncommon.

Well, at least we have June, July, and August, because it sometimes snows in September too.


The Vernal Equinox

Equinoxes occur twice a year, once in the spring (the vernal equinox) and once in the fall (the autumnal equinox). On the equinox, the number of hours of day and night are equal over the entire Earth. So, on the equinox northerly Barrow, Alaska (71°N), equatorial Bogota, Colombia (4°N), and Dunedin, New Zealand (45°S) all receive about 12 hours of daylight and 12 hours of night. If we flash back to the most recent solstice (December 21, 2014), we can see how different these times were. On the last winter solstice, Barrow received zero hours (or seconds!) of daylight. Poor Barrow. Bogota received 11 hours and 51 minutes of daylight (daylength varies little throughout the year near the equator). And Dunedin received a pleasant 15 hours and 44 minutes of daylight – the northern hemisphere’s winter solstice being the southern hemisphere’s summer solstice. So, while there was a great deal of variation between these locales on the solstice (nearly 16 hours from north to south), they all receive about the same amount of daylight on the equinox. 

 The vernal equinox is considered the first day of spring. While first signs of spring may vary based on your locale, this designation makes sense astronomically. The Earth doesn’t orbit the sun in a straight up and down alignment; it is tilted on its axis – this is why we have seasons. From a northern hemisphere perspective, during our winter the northern hemisphere is tilted away from the sun. During our summer, the northern hemisphere is tilted toward the sun. On the equinox, the celestial equator (the Earth’s equator projected out in space) passes through the center of sun. Which means, that neither the South nor North Pole are tilted away from the sun, so all parts of the Earth receive the same amount of sunlight. So, the moment before the equinox, the northern hemisphere is still (just barely) tilted away from the sun. The moment after the equinox, the northern hemisphere is now (just barely) tilted toward the sun. Thus, astronomically, the seasons have changed. The equinox marks the beginning of spring and spring will continue until the summer solstice (June 20-21). On the summer solstice, the northern hemisphere is tilted the most toward the sun it will get, so we receive the most amount of sunlight on that day. After the summer solstice, the northern hemisphere is starting to tilt away from the sun little by little until we reach the next equinox, and then the winter solstice, when we will start to tilt back toward the sun again.

If you are having trouble wrapping your mind around this, I found this video extremely helpful. I posted it here before. It really makes the whole concept much clearer to me. 


 As with the solstices, cultures throughout the world have celebrated the equinoxes for millennia. The Mayans built El Castillo at Chichen Itza around 900 A.D., where on the equinoxes, observers can see a huge shadow depicting the body of a wriggling serpent rise up along the stone wall. 


 A simple equinox celebration:

In much of the world, the new year is celebrated close to the winter solstice. This new beginning is often celebrated by making resolutions. People are filled with intentions of turning over a new leaf and beginning again. To me, this seems out-of-sync with the world around us, however. While sun is gradually returning to the land, we don’t see fresh starts or literal ‘new leaves’ around us (especially in places with cold winters). At the vernal equinox, however, the world is full of new beginnings. The snow is melting, buds may be forming, daffodils and tulips popping up through warming soil, and if not yet – they will be soon. I think this is a more appropriate time to think about starting fresh and new, leaving behind the old and opening yourself to the new.

Consider what has been holding you back or what has been keeping you down. What narrative have you carried with you through the winter that you are ready to let go of? Write it down on a piece of paper and take it outside to burn (safely) on your patio, in your firepit. Let it go; you don’t need to carry it with you any longer. Make room for fresh, new growth.

All Hail the Micro Moon!

Last Night’s Moon by Will C. Fry via Flickr

On Thursday, March 5, 2015 the full moon will be present in Earth’s sky. This month’s full moon is a “micro moon”. While the term  “super moon” seems to be widely recognized, its inverse, the micro moon, is less well known. The micro moon occurs once each year, though not always in March. Micro moon refers to a full moon that occurs when the moon is at its farthest point in its orbit from the Earth (known as apogee). The super moon is the opposite – a full moon that occurs when the moon is closest to the Earth (known as perigee). The difference is noticeable to the human eye, though is takes a keen one. Every year the mini moon returns one month and eighteen days later than the previous year. So next year, the micro moon will occur on April 22nd, in 2017 on June 9th, and so on.

March’s full moon has a number of names ascribed to it by the various Native tribes of the Americas. One name is the Full Sap Moon. March’s warmer weather causes sap to begin to run once again in the trees in March. Many Native tribes harvested maple sap each spring, including Minnesota’s Anishnabeg (Ojibway). The March full moon is likewise known as the Sugar Moon, because most of the tribes that collected maple syrup boiled it down until it crystallized, becoming sugar, making it much easier to transport.

From a 1896 European observer:

The season of sugar making came when the first crow appeared. This happened about the beginning or middle of March, while there was yet snow on the ground. This period of the season was looked forward to with great interest, and, as among the Minnesota Ojibwa today, became a holiday for everybody. Each female head of a household had her own sugar hut, built in a locality abounding in maple trees which might or might not have been convenient to her camp, but which was the place always resorted to by her, and claimed by right of descent through her mother’s family and totem. (Prentice, 26)

The March full moon is also the Snow Crust Moon, so called because of the crusty nature of March’s snow – resulting from daylight snow melt, followed by the nighttime freeze. The Algonquins of New England called the March full moon the Full Worm Moon, because in March the ground would thaw and the worms would wiggle out once again.

To me, these names all signal a recognition of the changing seasons that occur at this time of year. While in the northern part of the country, snow is still on the ground and no green is yet in sight, life is returning to the barren winter landscape – the sap is flowing, the worms squirming, and the character of the snow is shifting. Here in Minnesota, with a high temperature of 13 degrees F today, it doesn’t feel much like spring. Walking in the woods, I don’t see much sign of it at all. I am sure that the people who walked this land long before I did were much keener observers of the natural world, though. The one obvious sign of spring is the increase in daylight, of course. Today, we received 11 hours and 21 minutes of daylight, a significant increase over the meager 8 hours and 46 minutes we received back in December on the winter solstice. What signs of spring are you seeing where you live? What would your local March full moon be called?

Why isn’t the Solstice the Coldest Day of the Year?

cold as ice by matthias klaiber via flickr
cold as ice by matthias klaiber via flickr

After I wrote about the winter solstice back in December, I got to wondering why the solstice isn’t typically the coldest day of the year. Since we get our heat from the sun and on the winter solstice we receive the fewest hours of sunlight, why does the coldest day on average occur almost a month later (at least here in Minnesota – this map shows average coldest day across the US.)? On January 21st, we receive almost forty more minutes of sunlight then we do on December 21st, so why is January 21st on average the colder of the two days?

The answer is actually quite straight forward. It takes awhile to warm up! Technically, this phenomenon is known as the lag of the seasons. There are a few forces at work. First, the oceans and ground absorb heat from the sun. They are still hanging onto (and releasing) some of the heat they gathered up over the hot summer months into December. As we move past the solstice, deeper into winter, the amount of residual heat has decreased, so even though we are getting more sunlight, the temperatures still continue to drop.

One apt analogy is a tea kettle on a stove top. When you place the tea kettle on the stove and light the burner, it takes awhile for the water to absorb the heat. The water won’t be hottest thirty seconds after you turn in on, even if you’ve turned the burner all the way up; it takes some time for the water to warm up. Inversely, if after you have heated the water all the way up (this would be July or August on Earth) and then you turn the burner down to low, the water won’t be immediately cool. It will take some time (until January) to cool down to the minimum temperature.

Since the ocean is efficient at retaining heat, this is why some places along the ocean experience less seasonal change than one might expect given their latitudes. For example, London (51 degrees N) is farther North than Minneapolis (44 degrees N), but the average temperature of London in the winter is much warmer than in land-locked Minneapolis. Additionally, the average monthly temperatures in Minneapolis vary by 61.7F, while in London monthly temperatures vary by only 24.3F. The North Atlantic Current brings warm water up to London from the Gulf of Mexico. This water retains much of its warmth during its long Tranatlantic voyage into northerly latitudes, thus keeping temperatures in London much warmer than one would expect given the city’s latitude.

Another factor that slows down warming in the winter is snow cover. When the solar heat emitted by the sun is retained by the Earth, it leads to greater warming. However, abundant snow cover reflects the solar heat back into space, so that we don’t feel its full warming effects. This is like wearing a white t-shirt on a hot day in an attempt to stay cool. So, in the months with the most snow cover (December – February), solar heat retention is reduced.

This year in Minneapolis, we may already have our coldest day behind us. We had a stretch of several sub-zero days at the beginning of January, with a low of -11F on January 5th. Now, we are in the midst of a warming trend. We enjoyed a balmy 37F, sunny day today and we broke out the sleds and skis. It can’t last though, February will bring more cold weather, but hopefully we’ve seen the bottom and are on a (slow) path toward spring weather.

The Winter Solstice

Winter Sun by NietNagel via Flickr

December 21st is the winter solstice in the Northern Hemisphere. It is the shortest day of the year and, correspondingly, the longest night. On the winter solstice, the sun is the farthest south in the sky it will appear and it is the day of the year when the sun reaches its minimum noon altitude. The sun appears to hang at this altitude for a few days, and then turns and begins its journey back northward toward its highest noon altitude – the summer solstice on June 20th or 21st.

These phenomena are more drastic the farther you are from the equator. For example, Bogota, Columbia is just 4 degrees north of the equator. In Bogota on the winter solstice, there will be 11 hours and 51 minutes of daylight. On the summer solstice, Bogota will receive 12 hours and 23 minutes of sunlight. There is only 32 minutes of difference between the shortest day and the longest in Bogota. Let’s compare that to Minneapolis, MN at 44 degrees north. In Minneapolis, we will receive 8 hours and 46 minutes of sunlight on the winter solstice. On the summer solstice, we received 15 hours and 36 minutes of sunlight. So, there is a difference of nearly 7 hours of daylight between the solstices, compared to Bogota’s 32 minutes.

This becomes even more extreme as you go farther north. Let’s head to 71′ N – Barrow, Alaska. The sun will not rise at all in Barrow, Alaska on December 21st. In fact, the sun has not risen in Barrow since November 18. The sun will not rise again until January 23rd, on which day Barrow will receive a welcome one hour and eight minutes of sunlight. They will have gone 65 days since the last sunrise. Conversely, on May 11th, the sun will rise in Barrow at 1:46 a.m. and it will not set again until August 2nd. So, in Barrow, the difference in day length between the winter and summer solstice is 24 hours.

The solstices have been important in human culture for millenia. Imagine yourself living in a world deeply tied to nature and the seasonal cycle. Each day the world has been getting darker and darker. Cold has crept across the land. Nothing is growing. Death and decay seem to be conquering the world. But then, behold! The sun pauses in its sinking journey toward the southern horizon, and it turns back; gradually, the days start growing longer. The cycle of death and rebirth continue once again. This is something to celebrate!

From prehistoric artifacts, we know that the solstices were acknowledged by humans across the world from at least 3200 BCE. Artifacts that show recognition of the solstices have been found across cultures – in Ireland, Indonesia, and Peru, for example. The oldest of these artifacts we’ve discovered comes from Ireland. Just over 30 miles north of Dublin, a prehistoric tomb known as Newgrange overlooks the River Boyne. The tomb was built around 3200 BCE. If you are having trouble placing 3200 BCE in context, this was 500 years before the pyramids were built, a whopping 2400 years before the Greek city states emerged – we’re talking 5000 years ago here.There is a 60 foot passage in this tomb, at the south end of the passage is an opening that the sun shines in only on the winter solstice. On the solstice, the sun illuminates this inner passageway for 17 minutes. You can actually go and visit Newgrange on the winter solstice and witness this phenomenon for yourself, but you’ll have to win their yearly lottery for tickets, as the event is so popular.

Fire is the most wide-spread aspect of winter solstice celebrations. It is easy to see why – what better way to mark the darkest night of the year then by lighting candles and building bonfires? Part of this fire tradition includes the burning of the Yule Log. The roots of the Yule Log are somewhat mysterious, but may have originated in Northern Europe in the 6th century. The Yule Log (perhaps an entire tree in some places) would be burnt on the solstice and should be kept burning throughout the entire night. A portion of the Yule Log would be kept to be burnt in the next year’s fire. On some Yule Logs, a chalk outline of a man was drawn before the log was placed in the fire…perhaps a remnant of human sacrifice made on the solstice?

A simple solstice celebration:

If you would like to celebrate the winter solstice, it is quite easy to put together a simple celebration. I would start by taking advantage of the few hours of daylight that you have on the solstice (unless you are in Barrow, in which case, maybe leave Barrow?) by getting outside. Take your fellow celebrants out for a nature walk in a wooded area and hunt for the perfect Yule Log. What makes a perfect Yule Log? Go with your gut, you’ll know that Yule Log when you see it. Gather your Yule Log and bring it back home. If you have a fireplace, festivities can continue inside, if you prefer. If you are going to be celebrating outside, as the sun is setting (4:34pm here in Minneapolis), get a roaring bonfire going. If you celebrated last year and have a part of the previous year’s log, put that on the fire. Once the old log is burning well, add the new log. When the new Yule Log has just about burnt out, make sure you pull part of it out of the fire to save for next year’s celebration. I love a good poem and a celebration isn’t quite complete without one, in my opinion. As you sit around the fire, have one brave or dramatic soul in your party recite an appropriate poem (there are many). I like this one:

So the shortest day came
and the year died
And everywhere down the centuries
of the snow-white world
Came people singing, dancing,
to drive the dark away.

They lighted candles in the winter trees;
They hung their homes with evergreen;
They burned beseeching fires all night long
to keep the year alive.
And when the new year’s sunshine blazed awake
They shouted, reveling.

Through all the frosty ages you can hear them
Echoing behind us — listen!
All the long echoes sing the same delight,
This shortest day.
As promise wakens in the sleeping land;
They carol, feast, give thanks,
And dearly love their friends, and hope for peace.
And so do we, here, now,
This year, and every year.
Susan Cooper

While it might be traditionally appropriate to keep the fire burning all night long, I’m into sleeping, and it is cold in Minnesota in December. So, I’d recommend putting the fire out when everyone is tuckered. You can bring the party back inside, but – and this is key- don’t turn the lights on. Whatever hours of wakefulness remain should be spent without the use of artificial illumination. How nice to come in from the bonfire and light the house only with candles on the darkest night of the year. What a different atmosphere it will create from the average night! Contemplate the ways that companionship and celebration combat the darkness of the longest night, maybe even more so than the candles and the fire.

If you find the science side of the solstice interesting, you cannot miss the video below. The visualizations are amazing.

Long Night Moon

photo by Sigurd Rage via flickr
Full Moon Over Oak by Sigurd Rage via flickr

At 7:27 on the morning of December 6th, the moon will become, for an instant, full. Then, it will begin its steady process of waning once more toward the new moon. The December full moon has a number of traditional names attached to it. It is variously called the Long Night Moon, the Cold Moon, and the Moon Before Yule.

The Long Night Moon is quite an appropriate appellation for the December full moon. This full moon occurs close to the winter solstice – the longest night of the year. Moreover, because the moon rides high in the sky at this time of year, it is visible above the horizon for most of the night. Here in Minneapolis, the moon rises at 4:23 pm on December 5th and doesn’t set until 7:25 am on the 6th. That is just over 15 hours of full moon; Long Night Moon, indeed! A good night to be a werewolf or just a plain lunaphile like myself!

If you are here in Minnesota, the sky is perfectly clear across the state tonight and the weather is mild (relatively speaking) – step outside and get a glimpse of the Long Night Moon! If you miss it on Friday night, it will look just as full on Saturday night, so try again then!

St. Nicholas Day

St. Nicholas Day 2009 - St. Mary's Cathedral - 4 by Gary Bridgman via flickr
St. Nicholas Day 2009 – St. Mary’s Cathedral – 4 by Gary Bridgman via flickr

December 6th is the feast day of St. Nicholas. St. Nicholas Day goes largely uncelebrated in the United States, but in many countries St. Nicholas is the primary gift giver of the holiday season and his feast day supersedes Christmas as the main day of gifting. Where the holiday is celebrated, children put out their freshly polished shoes or boots on the windowsill on the evening of the fifth. That night, St. Nicholas visits children’s houses and fills their shoes with apples, oranges, almonds, candies, or other small gifts.

The details of the celebrations vary from country to country. For example, in the Netherlands, St. Nicholas takes the form of Sinterklaas who arrives in the country by boat from Spain in late November. Accompanying him is his servant, Zwarte Piet, dressed in the garb of a German mercenary (Zwarte Piet means ‘Black Pete’ and traditionally has been a white man dressed in black face. There is an ongoing controversy in the Netherlands about whether or not Zwarte Piet is a figure of racism, which I am not going to get into in this post! If you’d like to read more about the controversy, HuffPost has a decent summary here.)

The historical St. Nicholas lived in the fourth century and was bishop of Myra in Lycia (present day Turkey). This is why we still see images of St. Nicholas carrying a bishop’s crosier (staff with a curl at the top) and wearing a mitre (pointy bishop hat). St. Nicholas is said to have performed many miracles, given away his vast inheritance to the poor, and rescued the city in a time of famine. More than 400 years after his death, his bones were taken from Myra to the Italian harbor town of Bari, after which his popularity began to spread throughout Europe and his feast day became a more popular celebration.

A simple St. Nicholas celebration:

If you would like to celebrate St. Nicholas Day with your children this year, it can be done quite simply. On the evening of December 5th, tell a simple St. Nicholas story. Many St. Nicolas stories an be found here:

There are a wide-range of stories varying from the religious to the secular, so you should be able to find one that reflects your family’s beliefs.

Then, have your children clean a pair of their shoes or boots with a rag and set them either outside their bedroom door or by a windowsill. During the night, St. Nicholas can pay a visit and leave special treats inside the shoes such as oranges, chocolate, candy canes, a note, poem, or whatever else is special and at hand!