Long Range Discussion: Winter 2020-2021

[Nashville_Wx]

our geographic location used to not matter ... due to changes mainly to our climate unfortunately.... is the problem

While that has played a roleif you look back over the past I believe that snowfall records here are a bit harder to figure over a given time as localized events have happen year to year. If the airport does not report it it never happened. Point being averages per county drastically changes. I have been here years before most of you showed up... We broke it down to the freaking T! What we learned was most storms come from a random wave that just happens to work with the cold , at the same time. As a whole yes it is getting warmer but we are in a terrible region for snowfall, even if we can get colder temps of the past. Urban heat islands , there is a lot that plays to this in the South.

[Thundersnow]

While that has played a roleif you look back over the past I believe that snowfall records here are a bit harder to figure over a given time as localized events have happen year to year. If the airport does not report it it never happened. Point being averages per county drastically changes. I have been here years before most of you showed up... We broke it down to the freaking T! What we learned was most storms come from a random wave that just happens to work with the cold , at the same time. As a whole yes it is getting warmer but we are in a terrible region for snowfall, even if we can get colder temps of the past. Urban heat islands , there is a lot that plays to this in the South.

Put in statistical terms, we have a very high standard deviation on snowfall averages in this region.

A single blockbuster storm could make the difference between a nothing season and a season that appears above normal. The "average" doesn't mean a whole lot with a tiny sample set. It's just a point in the middle between nil to low figures and higher outliers that all average out.

[schneitzeit]

Let's have a look at some "season-saving" events, where a single storm placed a winter snowfall at average or above average. These are to the best of my memory.

March 1993 Superstorm: 10-20+" totals for all of East Tennessee after almost nothing the entire winter.
March 7-8, 2008 Snowstorm: Pretty much statewide. Came in to the rescue after a lousy winter. High temperatures were in the 80s the weekend before this event.
March 1, 2009 Snowstorm: Smacked West Tennessee and produced significant snowfall in southern Middle Tennessee.
November 2011 Early Season Snowfall: West Tennessee locations such as Jackson pick up as much as 6" in this historically early snow. Nothing much to report after this storm, as the winter of 2011-2012 was very warm.
Winter Storm Jonas, January 22, 2016: Knockout snowfall totals for Nashville metro, especially north of the city. As much as 12" in Robertson and Sumner counties. The only season snowfall above 1 inch for the whole winter for most of those places.
December 10-11 2018 Snowstorm: Affecting NE Tennessee, this was a big snowstorm dropping 1 foot totals on the Tri-Cities. Nothing much to report after this.
February 8, 2020 Chattanooga Snowstorm: 4-5" of snow in a single day's storm produces Chattanooga's seasonal snowfall average.


It takes a single storm to make all the difference. It can come anywhere from November to March. I'm sure the board's older residents will give you some more instances. I was born in 1997 for goodness sakes, and I have that much to offer already.

[gcbama]

Put in statistical terms, we have a very high standard deviation on snowfall averages in this region.

A single blockbuster storm could make the difference between a nothing season and a season that appears above normal. The "average" doesn't mean a whole lot with a tiny sample set. It's just a point in the middle between nil to low figures and higher outliers that all average out.

I get what you are saying, however I distinctly remember almost every other winter from 90's until early 2000's we would get about 2 decent events of 3-5 inches across a lot of the mid- state whereas the past decade it is sparse at best. The past 4 years I have gotten about 4 inches of snow total in all those four years combined, so something has changed, but again I believe it's cyclical and will come back around at some point

[BRUCE]

I get what you are saying, however I distinctly remember almost every other winter from 90's until early 2000's we would get about 2 decent events of 3-5 inches across a lot of the mid- state whereas the past decade it is sparse at best. The past 4 years I have gotten about 4 inches of snow total in all those four years combined, so something has changed, but again I believe it's cyclical and will come back around at some point

i was a young boy during 70s  remember we get 3 to 4 snows a year   Easily

[Thundersnow]

I get what you are saying, however I distinctly remember almost every other winter from 90's until early 2000's we would get about 2 decent events of 3-5 inches across a lot of the mid- state whereas the past decade it is sparse at best. The past 4 years I have gotten about 4 inches of snow total in all those four years combined, so something has changed, but again I believe it's cyclical and will come back around at some point

It's interesting to note the difference of perspective based on age and personal experience. I think I have about a decade of years on you. So, I remember growing up in the late 1970s and 1980s, coming of age in the early 1990s, and already well into adulthood in the early 2000s.

When we started this forum, I think around 2006, I remember a lot of discussion about, "it sure doesn't snow like it used to." My perception is there's basically been a snow drought in this region for most of the last 30 years, to be honest.

Back in those days I remember our comparing annual snowfall records back over the decades. I even created a graph that demonstrated snowfall trends over time in cities in TN.

The last 10 years were really not much worse than the 1990s in my mind. We had a few exception years with decent snowfall... such as 1996, 2003, and then around 2010-2011, but really that was about it. Other than that, a few spots "lucked out" with ULL systems that gave big events that missed the rest of the state. I noticed an uptick in snow around about 2010 and was hopeful the cycle might be turning a corner back to a longer term snowier pattern, but that didn't really pan out. So, there's kind of a IMBY (what happens "in my back yard") bias we all have to an extent.

So, all that to say- (and no jab intended on this)- it's a little funny to me when people say, oh it sure doesn't snow like it did in the 1990s and early 2000s, when I was thinking during those years, "it sure doesn't snow around here like it did back in the 1980s."

[JayCee]

2014-15 was an uneventful winter until a two week "cold snap" in February and early March brought below zero temperatures into much of TN, along with multiple snow and ice events.  Strangely enough, that winter was the 19th warmest in the U.S.  And while we were in the ice box, much of the Northern Hemisphere was unusually warm.   We just happened to be in the sweet spot, where what cold there was in the Arctic was being directed into the eastern U.S.

Here is what NOAA had to say about February 2015:

In all, NOAA said about 30.6 percent of the country was “very warm” – meaning February was in the warmest 10 percent of the historical record – while 31.5 percent of the country was “very cold,” or in the coldest 10 percent historically. Out of the 1,442 months in NOAA’s dataset, only one other (October 1988) has ever seen very warm and very cold conditions each claim more than 30 percent of the country in the same month.

[StormNine]

Let's have a look at some "season-saving" events, where a single storm placed a winter snowfall at average or above average. These are to the best of my memory.

March 1993 Superstorm: 10-20+" totals for all of East Tennessee after almost nothing the entire winter.
March 7-8, 2008 Snowstorm: Pretty much statewide. Came in to the rescue after a lousy winter. High temperatures were in the 80s the weekend before this event.
March 1, 2009 Snowstorm: Smacked West Tennessee and produced significant snowfall in southern Middle Tennessee.
November 2011 Early Season Snowfall: West Tennessee locations such as Jackson pick up as much as 6" in this historically early snow. Nothing much to report after this storm, as the winter of 2011-2012 was very warm.
Winter Storm Jonas, January 22, 2016: Knockout snowfall totals for Nashville metro, especially north of the city. As much as 12" in Robertson and Sumner counties. The only season snowfall above 1 inch for the whole winter for most of those places.
December 10-11 2018 Snowstorm: Affecting NE Tennessee, this was a big snowstorm dropping 1 foot totals on the Tri-Cities. Nothing much to report after this.
February 8, 2020 Chattanooga Snowstorm: 4-5" of snow in a single day's storm produces Chattanooga's seasonal snowfall average.


It takes a single storm to make all the difference. It can come anywhere from November to March. I'm sure the board's older residents will give you some more instances. I was born in 1997 for goodness sakes, and I have that much to offer already.

I would add the Feb 2nd-4th 1998, December 23-24th 1998 (although that was largely sleet and freezing rain), the 2002 surprise snow, and December 22nd-23rd 2004 (for West and NW Middle TN) to that list.   

[StormNine]

The PNA is looking to go positive as we head into December. 

If we had more cooperation in the arctic then I would be more excited, but a +PNA as long as it verifies and sticks around will prevent us from going full-blown torch. 

[gcbama]

It's interesting to note the difference of perspective based on age and personal experience. I think I have about a decade of years on you. So, I remember growing up in the late 1970s and 1980s, coming of age in the early 1990s, and already well into adulthood in the early 2000s.

When we started this forum, I think around 2006, I remember a lot of discussion about, "it sure doesn't snow like it used to." My perception is there's basically been a snow drought in this region for most of the last 30 years, to be honest.

Back in those days I remember our comparing annual snowfall records back over the decades. I even created a graph that demonstrated snowfall trends over time in cities in TN.

The last 10 years were really not much worse than the 1990s in my mind. We had a few exception years with decent snowfall... such as 1996, 2003, and then around 2010-2011, but really that was about it. Other than that, a few spots "lucked out" with ULL systems that gave big events that missed the rest of the state. I noticed an uptick in snow around about 2010 and was hopeful the cycle might be turning a corner back to a longer term snowier pattern, but that didn't really pan out. So, there's kind of a IMBY (what happens "in my back yard") bias we all have to an extent.

So, all that to say- (and no jab intended on this)- it's a little funny to me when people say, oh it sure doesn't snow like it did in the 1990s and early 2000s, when I was thinking during those years, "it sure doesn't snow around here like it did back in the 1980s."

Makes sense to me, its clear to see those massive snows in 60's and 70's were alot bigger than anything from 90's and 2000's.
But there were more events not alot of massive ones though in 90's early 2000's than there have been in the past decade for me, perspective is right lol

[BRUCE]

The PNA is looking to go positive as we head into December. 

If we had more cooperation in the arctic then I would be more excited, but a +PNA as long as it verifies and sticks around will prevent us from going full-blown torch.

EPS is saying, not so fast my friend...

[schneitzeit]

EPS is saying, not so fast my friend...

I'm really not sure what you're talking about. The EPS shows a dip in the heights by late Nov/ early Dec.

[BRUCE]

I'm really not sure what you're talking about. The EPS shows a dip in the heights by late Nov/ early Dec.

going by latest temps map I observed

[schneitzeit]

going by latest temps map I observed

I wouldn't call it a torch, man. Temps look average.

[StormNine]

If the polar vortex wasn't being a turd we would have a shot at below-average temperatures, but with the main ridging to our west and northwest, we should avoid the widespread torch temperatures we saw in 1998 and last year.