2020 Weather Recap

KNOXVILLE, Tenn. (WATE) — Our forecast for the 2020 winter was pretty good. Our snowfall forecasts were very close for the Valley and were just slightly under for some of the Plateau, Kentucky and the Smokies.

It was certainly a nice present for many with the Christmas Eve snowfall of around 2″-4″ across the region giving us a rare White Christmas in East Tennessee. We had a forecast for above-average temperatures for the months of December, January and February and we ended up being right at average for the 3 month period.

Expectations for this year’s winter

Once again a moderate La Niña pattern is influencing the Pacific Ocean off the west coast of South America. This can have some impacts on our weather across the entire United States, including a slightly warmer and slightly wetter than average winter, similar to last year.

Here is a month-by-month breakdown of what we’re expecting temperature-wise:

• For December, it looks as though we could see a below-average temperature trend for the month. In fact, we are thinking this may be where we could see the majority of our coldest air for the season.
• January appears to provide an average to above temperatures where we see a slow warming trend for the second half of the month.
• February looks to hold above-average temperatures where we could actually see an early transition to spring toward the end of the month.
• We are also giving you a “wild card” forecast for March because IF we do see a warmer February and an “earlier’ spring, it could lead to a more active and earlier start to our severe weather season across East Tennessee.

A look at past Winters

Let’s take a look back at how much snow the Knoxville area has seen since 2013 and how it could’ve been influenced by La Niña, El Niño or Neutral years.

From past research, the Knoxville area seems to have some of its biggest snows during Neutral phases on the El Niño Southern Oscillation including 1960 when we saw a whopping 56.7″ of snow. More recently, the years of 2013 and 2014 provided some decent snowfall totals as well between 9″ and 13″.

During an El Niño cycle, we can sometimes see slightly higher than average values like in 2015. On the other hand, we often see below-average snowfall during La Niña cycles like in the years 2017 and 2018.

Where did all the snow go?

If you have lived in the area long enough or know someone that has, you may have said or heard, “we always had more snow when I was younger”. And do you know what? They are right.

Our average yearly snowfall values for East Tennessee have decreased steadily since the early 1970’s going from an average of nearly a foot per year all the way down to around four and a half inches now.

Snowfall estimates for 2021-22 Winter

Here is our bottom line for what we are thinking this season. A La Niña pattern is certainly back this year and it appears as though it could be a moderate one which would lead us to believe that we will see a slightly warmer and wetter than average December to January period.

For snowfall estimates, we think the Valley will see right at average values of between 3″ to 5″ based on the latest 4.6″ yearly averages released by NOAA earlier this year.

Our forecast for the Plateau is between 8″ to 18″ which is slightly above average, but these higher totals would be for the higher terrain areas with higher elevations.

For the Southeast Kentucky/Southwest Virginia area, we think between 8″ to 14″ are possible which is just slightly above the yearly averages.

Finally, for the Smokies, we think this area will also see right at average totals of between 40″ to 70″ across the highest peaks.

The wetter than average forecast we’re expecting could aid in some higher isolated snowfall values if they correspond with some colder air pushing into the region at the same time, but that looks to be an exception rather than the rule in a La Niña pattern. The more likely scenarios for this season would be for more borderline snow events. like a chilly rain or mixed events of freezing rain or sleet.