December 2020 Weather Recap: Two Storms Grab Headlines

 

 

The lasting memory of December 2020 will no doubt be the snowstorm of Dec. 16-17.  The 10.5" of snow that piled up was the biggest snowfall in December since 2010, and the thirteenth December snowfall of 10"+.  Another highlight was the intense rainstorm that blew through the City on Christmas morning.  The month was 1.7 degrees above average - the City's 34th mildest December (since 1869).  But despite being milder than average, it had more days with highs of 32° or colder than all of last winter (four vs. three).  Additionally, the big snowstorm produced more than twice as much snow as the previous winter (10.5" vs. 4.8").

 

• Five days had highs of 55° or milder while six days had lows of 25° or colder.  There were three days with highs in the low 60s, evenly spaced, on 12/1 (62°), 12/13 (62°) and 12/25 (61°).  Five of the six days with lows of 25° or colder had lows of 24° (the outlier was the reading of 20° on 12/19).

• The mildest and coldest periods of December occurred during the fifteen-day period from Dec. 11 thru Dec. 25.

 

 

• Christmas Day's high of 61° (before sunrise) made it the eighth Christmas with a high in the 60s, and the 0.92" of rain that fell was the third greatest amount on the holiday.  After the high was reached, the temperature fell steadily throughout the day and was down to 29° by midnight.  This 32-degree drop was the greatest of any calendar date in 2020.

• Although the month was on the mild side, five Decembers in the past ten years were even milder.

 

 

• December 2020 was the 29th December with ten or more inches of snow (nearly 20% of all Decembers).  However, it was the second mildest December (after Dec. 1912) to have this much snow.  Although their average temperatures weren't quite as mild as this December, the Decembers of 1948, 1959 and 2003 had considerably more snow (25.3", 15.8" and 19.8", respectively).

 

 

• Much of the month's 4.61" of precipitation (0.61" above average) fell from three storm systems, all which produced more than an inch of precipitation:  1.13" on Dec. 4-5; 1.52" on Dec. 16-17; and 1.16" on Dec. 24-25.

• Finally, similar to November, December had a lot of days with gusty winds, with Central Park having nine days with a peak gust of 33 mph or more.  The peak gust of 47 mph occurred early Christmas morning.

 

 

 

Other December recaps:

2019

2018

2017

2016

2015

 

 

 

Comments

[William]

this month was 13.8 degrees colder than last month. when was the last time December was 13.8 degrees or more colder than November?

[Rob]

The last time December was colder than November by such a wide gap was in 2010 (15.1 degrees colder). And it happened in 2009 as well (15.3 degrees). December 2020 was the 29th time December was 13.8 degrees or more colder than November - an average of about once every five years, so it's not all that rare. However, December 2020 has the distinction of having the mildest average temperature for any December that was 13.8 degrees or colder than November.