October 2020 Weather Recap: 'Mother Nature' Dresses Up as 'Jack Frost' for Halloween

 

 

October 2020 was slightly milder and wetter than average in New York.  The month's first week-and-a-half was uneventful, with just 0.06" of rain.  Then three significant rain events soaked the City, each bringing more than an inch of rain: 1.30" fell on 10/12-13; 1.36" on 10/17 and 2.17" on 10/29-30.  The first and third rainmakers were from remnants of hurricanes Delta and Zeta.  The month ended up with 5.05" of rain, 0.65" above average.  Overall, the month was one degree above average, making it the 11th October in a row that was milder than average.  The low was nearly two degrees above average while the high was just about average (+0.1 degree). 

 

Until the end of the month the chilliest reading had been 44°, which would have been one of the mildest readings for this distinction in October (October 1946's and 1971's coolest reading was 45°; October 2007's was 44°; last October's was 43°).  But then a shot of Arctic air followed the rainstorm of 10/29-30 and Halloween morning dawned with a low of 32°, the coldest reading in October since 1988.  This was three weeks earlier than the average date of the first freezing or colder reading in Central Park.

 

 

The month's mildest reading was 74° (on 10/7), which was the coolest warmest reading in October since 2009, which also had a mildest reading of 74° (October 2009 was the last time the month was chillier than average).  The last time the warmest reading was cooler than this was in 1987, when it was 72°.  (By contrast, last October's warmest reading was a sizzling 93°.)  There were just six days with highs in the 70s (the October average is nine), none of which occurred back-to-back.  This was just the third time this has happened in October in the past 100 years.  And this October was the only one of the three that was above average temperature-wise.

 

Although the month was one degree milder than average, both the warmest and chilliest readings of October were six degrees cooler than what the average warmest and chilliest readings are in October.

 

Finally, there were just eight days with mean temperatures five degrees or more above average, and four days that were five degrees or more below average.  The lengthiest streak of days that were five degrees or more above average was five (10/20-24); this streak was nine degrees above average (high/low of 69°/58°).  There were no extended periods of significantly chillier than average temperatures, but the last two days of the month were twelve degrees below average (high/low of 47°/34°).

 

 

Here are previous recaps of October's weather:

2019

2018

2017

2016

 

 

 

 

Comments

[Joaquin]

Also, the first warmest reading cooler than 80+ since 2015.

[Henry]

Halloween 2020 had a high/low of 46/32, producing a mean temperature of 39. This was the coldest October day since 10/29/2011 (high/low of 45/33), the day a ridiculously early snowstorm hit New York City and New England.

[Gerry]

Would you know if this year had the shortest time between latest (May 9) and earliest sub-35 temps?

[Landen]

March had a warmer reading than October (77 vs 74). Has this happened or no? Is 1989 (82 in March vs 77 in October) the only other year in which this happened?

[Rob]

Besides 1989 and 2020, March's warmest reading has topped October's in 10 other years (going back to 1900): 1998 (86 vs. 74); 1990 (85 vs. 84); 1987 (76 vs. 72); 1985 (82 vs. 80); 1981 (77 vs. 71); 1977 (81 vs. 70); 1945 (86 vs. 80); 1929 (77 vs. 74); 1923 (76 vs. 74); and in 1921 (84 vs. 77.)

[Jeffrey Hirschman]

If it gets to 75 degrees this week when was the last time November's highest reading exceeded October?

[Rob]

The last time for such an occurrence was in 2003, when the warmest temperature in November was 79 while the warmest reading in October was 77. And it's happened in six other years since 1900: 1929, 1974, 1981, 1987, 1993 and 1994.