2019 2020 Season Forecast

2019-2020 Snow Forecast
December 1, 2019

For the past two years, KingstonSnows has been issuing seasonal snow forecasts. Last year the forecasts called for 34 inches with a likely range of 22 to 46 inches - the season total was 46.2 inches. The year before called for 48 inches with a likely range of 35 to 61 inches - the season total was 51.3 inches.

2017-2018
(issued December 12, 2019)
2018-2019
(issued January 2, 2019)
Forecast 48 inches
Likely range of:
35 to 61 inches
34 inches
Likely range of:
22 to 46 inches
Actual Total 51.3 inches 46.2 inches

In both years the forecast was based on what I'm calling the "Second Snow Rule". This is an observation in KingstonSnows data since 2004 that there is a fairly strong correlation between the date of the second snowfall of the season and the total snowfall for the season. Many people wonder about if an early first snow has any indication for the season ahead; however, it generally does not. Since 2004 in Kingston, if one were to use the date of the first snowfall to estimate the season total, the forecast would off by an average of 40 inches - that is a very significant error. However, if one were to use the date of either the second or third snowfall to estimate the season total, the forecast would be off by a more acceptable average of 12 inches.

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Caption: The purple dots represent calculations of season snowfall based off the first snowfall. The green dots represent calculations of season snowfall based off the second snowfall. The closer the dots are to the red line the more accurate they were. Click image for larger and clearer version.

So far this winter, we have had two measurable snowfalls: November 12th, November 19th, and today - December 1st. Using the correlation of the 1st snowfalls, a season total of 80.4 inches +/- 40.6 inches would be expected. Using the more accurate 2nd snowfall approach, 75.0 inches +/- 12.5 inches would be expected, and using the 3rd snowfall correlation, a season total of 69.8 inches +/- 12.6 inches would be expected. Because the 2nd and 3rd snowfalls actually have same average error, I am going to use a blend of them this year - the last two years were based on just the 2nd. Based on this, a total of 72 inches, is being forecast with a likely range of 60 to 84. This is well above Kingston's average season total of 44.9 inches.

2019 - 2020 Snow Forecast:
72.0 inches
Likely range:
60 to 84 inches

Although the forecast anticipates a likely range of 60 to 84 inches, the averages suggest that there is about a 25% chance of less than 60 inches of snow, and about a 25% chance of more than 85 inches of snow. If this forecast verifies, this will be the snowiest winter since 2004-2005 when 72.4 inches fell.

We'll see how the forecast holds up by April!

-Ethan

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