Quantcast

Monthly Recap Feed

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

New york in fall 2020

 

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.

 

Jack_frost

 

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.

 

Chart - back to back 70s in Oct

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°).

 

Geese on the pier

 

Here are previous recaps of October's weather:

2019

2018

2017

2016

 

 

 

 


September 2020 Weather Recap: Cool & Dry Conditions Sandwiched Between Mild & Wet

September 2020

 

September 2020 was a touch milder than average (+0.8 degree), with close to an average amount of rain (3.94").  The month's story can be told by three eight-day periods: Sept. 3-9 was four degrees above average, Sept. 23-30 was six degrees above average, and the middle of the month (Sept. 15-22) was six degrees chillier than average, and rain-free.  Nearly all of the month's nearly four inches of rain was produced by three storm systems: 0.71" on 9/3, 1.20" on 9/10 and 1.61" on 9/29-30. 

 

The month's near average rainfall belied a 16-day streak with no measurable rain (Sept. 11-26).  This was the longest dry streak since the fall of 2017.  These dry conditions were largely due to a strong high pressure system that anchored itself over the Northeast for about a week.  It prevented moisture from hurricane Sally and tropical storm Beta from moving into the area and brought chilly air into the region, delivering the City's earliest lows in the 40s in seven years (49° on 9/21, 48° on 9/22).

 

Just seven days had highs of 80° or warmer, joining ten other Septembers since 1970 with this few.  The warmest reading was 85°, occurring on 9/3 and again on 9/4 (a typical September's hottest reading is around 90°).  The month's average high of 75.5° was the coolest since 2009.  And although the month's average temperature was a touch above average, it was the coolest September since 2013.

 

Chart - septembers by decades

 

Finally, although highs in the 80s/90s and lows in the 70s occasionally occur in October, if 2020's final reading of 80°+ remains at 9/10, it will be one of the earliest dates on record for this occurrence.  Meanwhile, the 58 lows of 70°+ is the third most after 1906 (61) and 2005 (60). 

Here are previous September recaps:

2019

2018

2017

2016

2015

2014

 


August 2020 Weather Recap: A Continuation of Summer's Above Average Temperatures

Isaias august 2020

 

Like June and July, August was warmer than average, but not to the degree of the two preceding summer months.  It was 1.7 degrees above average and the 23rd hottest August on record.  This followed June, which was 16th hottest (2.3 degrees above average), and July, which was 7th hottest (+3.5 degrees). There were no scorching heat waves, but the number of days with lows in the 70s was above average.  Tropical storm Isaias, which struck on the 4th, was August's weather highlight, followed by a thunderstorm on the 12th that was the month's biggest rain maker.  Overall, the month's 5.03" of rain was a touch above average.

 

There were four days in the 90s and six days with highs of 88° or 89°.  Hottest reading of the month was 92°. The two days with the warmest lows (78° on Aug 2 and 77° on Aug 11) failed to have highs of 90+.  There were no heat waves and none of the days in the 90s were back to back.

 

Tropical storm Isaias was largely a wind event, with well under an inch of rain measured.  A gust of close to 50 mph was clocked in Central Park while the area's major airports all had gusts around 70 mph.  By comparison, a severe evening thunderstorm eight days after the tropical storm produced 1.76", more than three times the amount from Isaias (0.55").

 

This was the seventh August in a row with no lows in the 50s (coolest reading was 62°).  There were 19 days with lows in the 70s, which was well above average (13).  Only six Augusts have had more; five others also had 19.  However, the number of days with lows of 75°+ was just slightly more than average, ranking 29th (and tied with six other years).  The fourth longest streak of days with lows of 70+, 20 days, ended on 8/7 (just two shy of the longest streak).

 

Finally, the summer of 2020 was the fourth hottest on record (tied with 1983).  However, it was tied for fourth warmest average low, but 18th hottest average high.  Although rainfall was slightly above average, it was enough to make 2020 the second wettest of the ten hottest Augusts (just 0.11" behind 1983).

 

Chart - 10 hottest summers

 Dog days of summer

 

Here are previous August recaps:

2019

2018

2017

2016

2015

 

 


July 2020 Is Seventh Hottest; Drought Eases Up

Seventh place

 

Following a June that was 2.3 degrees warmer than average, July 2020 was even more above average, +3.5 degrees, with an average high/low of 87.4°/72.6°.  The month's average temperature of 80.0° made it the seventh hottest July on record.  July records were set for mildest reading for coolest low temperature (67°) and the most lows in the 70s/80s (26).  Additionally, it joined eight other Julys with 14 or more highs of 90° or hotter.  Low temperatures were instrumental in placing the month so high in the rankings as it was third warmest in that category while the average high was ranked sixteenth.  Precipitation was also a significant story as the 6.58" that fell made this the wettest month of the year, so far, and the wettest of the 15 hottest Julys (July 2019 previously held that distinction).  Tropical storm Fay contributed a significant portion of the month's rainfall.

 

As mentioned above, July had 14 days with highs in the 90s, the most since 2010.  This included two five-day heat waves.  Despite the large number of hot days the heat wasn't overbearing as only one day had a high of 95° or hotter (96° on 7/6).  This was the fewest of any July among the 10 hottest.  However, there were nine days with lows of 75°+ (tied for fifth most of any July), including two in the 80s (the counterpart to high temperatures in the triple digits).  And of the six days with below average mean temperatures, just one of them had a low temperature that was cooler than average.

 

Highline during covid-19
.

After an exceedingly dry May and June, with both months reporting less than two inches of rain, July had 6.58", making it the wettest month so far this year (nearly double the combined rainfall of the preceding two months).  More than half of the rain was from tropical storm Fay on 7/10 (2.54") and a severe thunderstorm the evening of 7/22 that dumped 1.23" in an hour.  (Newark Airport, just 20 miles to the west, was much rainier, with 11.17" measured - its wettest July on record).

 

Chart - july 2020 top 10 julys

 

Finally, June and July 2020 were the seventh warmest June-July combination.  And the number of lows of 70°+ in June and July (37) tied June-July 2010 for the greatest number.  (37 is the  average number for an entire year.)

 

Chart - hottest june_july combos

 

Here are previous recaps of July from 2014 thru 2019:

July 2019

July 2018

July 2017

July 2016

July 2015

July 2014

  Tropical


 


May 2020 Weather Recap - Chilly & Dry

Polar vortex of may 2020

 

May 2020 was 2.1 degrees below average, and followed an April that was also cooler than average (-2.7 degrees).  The last time back-to-back months had below average temperatures was in March and April 2018.  This was the chilliest May since 2008.  What made the month cooler than average was the 10-day period between May 5-14, which was nine degrees colder than average.  (The month's other 21 days were slightly above average.) 

 

The brunt of the extended cold period mentioned above was May 9, when the high/low was just 48°/34° (nineteen degrees below average).  The day's low reading was the coldest reported in May since 1891.  Previous to this May, the last one with a reading in the 30s was in 1978 (38°).  Lows were in the 30s for three consecutive days, May 8-10 - just the fourth May with a cold streak of this length, joining 1891, 1923 and 1947.  Besides the chilly air, snow flurries fell before daybreak, tying May 9, 1977 for the latest date with a trace of snow.

 

Cold in may
 

May was also a dry month.  With just 1.65" rain measured, this was the driest May since 2005 (and fourth driest since 1970, and 22nd driest among all Mays).  This amount was 60% below average (a deficit of two-and-a-half inches).  The wettest day was the Saturday of Memorial Day weekend when 0.65" was measured, with most of this amount pouring down between 11 AM and noon.  This was the rainiest Memorial Day Saturday since 1982.

 

Before the unseasonable Arctic outbreak of May 5-14, May began on the mild side, with the first four days four degrees above average.  5/1 snapped a 16-day streak of cooler than average temperatures; 5/2's high of 73° was the first reading in the 70s in more than six weeks; and May 3 saw the year's first reading of 80°+ - the first time since 2014 that a year's first 80 didn't occur in April. 

 

May's warmest reading, 84°, came six days after 5/9's frosty reading of 34°.  This was the first May since 2008 to have no readings of 85° or warmer.  (A typical May's warmest reading is in the upper 80s.)  The warmest mean temperature was on 5/29 and 5/30, both with a high/low of 81°/67° (eight degrees above average). 

 

Finally, there were a dozen days with lows cooler than 50°, double the average amount (since 2000) and the most in May since 2008. 

 

Here are recaps of the previous five Mays:

2019

2018

2017

2016

2015

 

 

 


April 2020 Weather Review: First Cooler Than Average Month of the Year

April 2020

 

April was 2.7 degrees below average, making it the first month this year to be chillier than average.  It was also the fourth chilliest April of the past 40 years.  Even more interesting, this was the first April since 1940 with no highs of 70° or warmer (after three such days in March).  In the years since 2000 the warmest reading in April has averaged 85°, but this April's mildest reading was just 68°.  Despite this cool warmest reading, the nights weren't as cold as might be expected as the coldest reading, 36°, was three degrees milder than a typical April's coldest temperature.  The 32-degree difference between the month's coldest and warmest readings was 20 degrees less than the average difference between the two extremes - the smallest gap of any April on record.

 

The last sixteen days of the month all had below average mean temperatures, the longest below average streak since March 2018's streak of 22 days.  These 16 days were seven degrees below average (seven of the days were ten or more degrees below average).  Before this streak started April had been two degrees milder than average (with April 4-8 seven above average).

 

Although it was the fourth coldest April of the past 40 years, it ranked 63rd among all Aprils going back to 1869.  This was due to the fact that Aprils before 1940 were much chillier.  (Six of the eight Aprils with no high readings of 70° or warmer occurred between 1873-1884.)

 

Cool-ish

 

Although April's rainfall, at 4.49", was an average amount, it was enough to make it the rainiest month so far this year.  The month also had the year's biggest rainstorm - 1.92" on 4/13 (the day after Easter).

 

A typical April is 10 to 11 degrees warmer than March, but April 2020 was just 2.4 degrees milder - the third closest of any year.  Additionally, April's mildest reading was nine degrees cooler than March's (68° vs. 77°) and its mildest low temperature was one degree cooler than March's (53° vs. 54°).

 

Chart - closest april-march temp
 

2020 is just the seventh year in which April, March and February had more precipitation than the month preceding it. This year April had 4.49"; March, 3.78"; February 2.54"; and January 1.93".

Chart - first 4 months of rain

 

Here are April recaps of previous years:

2019

2018

2017

2016

 

     


March 2020 Weather Recap - 8th Mildest on Record

Nyc-covidjpg

 

March 2020 was 5.5 degrees milder than average, becoming the eighth mildest March on record.  By coincidence, this  followed an eighth place ranking for February 2020.  Only one day had a low of 32° or colder (a typical March has twelve such days), occurring on the first day of the month when the mercury fell to 25°.  The month's warmest reading was 77° on 3/20.  For the third month in a row precipitation was below average, but the 3.78" that was measured was the most of the three months.  The year's rainiest and second rainiest days, so far, occurred on March 23 (1.19") and March 19 (0.93").  Like February, just a trace of snow was reported, only the second winter in which this occurred (the other winter was in 2002).

 

 Chart - 10 mildest marches

  Chart - least snow feb-mar

 

Here are previous March recaps:

2019

2018

2017

2016

 

 

 


February 2020 Weather Recap - Mild & Snow-Free

8th place

 

After a January that was the eleventh mildest on record, February ranked even higher, at #8 (and it was the third mildest Leap Year February, behind 2012 and 1984).  This was the third February of the past four to rank among the ten mildest.  But despite it being the mildest of this winter's months it had the coldest temperature of winter, 14° on 2/15.  (However, the coldest day of winter continued to be Dec. 19, which had a high/low of 25°/16°.)  In addition to being the seventh mildest February (4.8° degrees above average) it was the sixth February with no measurable snow (the last time was in 2002).  Other observations:

 

  • Similar to December and January, February had just one day with a high of 32° or colder (and each month had four days with highs of 35° or colder).  By comparison, a typical meteorological winter has a sixteen days with highs of 32° or colder.  Speaking of the winter, winter 2020 was the sixteenth to have December as the coldest of the three months.  And this was despite December's average temperature being slightly above average.
  • Three-quarters of the month's 2.54" of rain fell between Feb. 6-13.
  • After being nine degrees above average during the first thirteen days of the month, the rest of February had temperatures closer to the norm - two degrees above average.
  • Although it was milder, February had one more day with a low of 32° or colder than January.  Despite the month's mild temperatures just two days were in the 60s.  The highs on these days, 61° (on 2/4) and 62° (2/24), were not nearly as mild as January's mildest highs of 69° and 68°.
  • This was the driest January-February since 2009.  (February was the driest in three years, January was the driest in eighteen years.)  Jan-Feb 2020 ranks among the twenty driest first two months of a year.
  • After January missed by a small margin being the tenth mildest, February missed by an even tinier margin of being seventh mildest.

 

Chart - Jan Feb Photo Finishes

(If Leap Year Day hadn't been so chilly, with a high/low of 35°/25°, February 2020 would have finished as seventh mildest rather than eighth.)

 

Previous February recaps:

2019

2018

2017

2015

 

 

 

 

 


January 2020 Weather Recap: Mild, Dry, Largely Uneventful

Mild

 

January 2020 was the 11th mildest January on record (6.4 degrees above average).  Only six days had below average temperatures; just one had a high of 32° or colder, joining 10 other years with either no such days or one.  The month's highlight was the May-like temperatures during the second weekend of the month when record-setting highs of 69° and 68° were reached.  The coldest reading was 20°, which happened on three days (January's coldest temperature is typically around 9°).  Looking at precipitation, this was the driest January since 2002, with a little less than two inches measured (half the typical amount).  As for snowfall, only 2.3" was measured (but double last January's total).  

 

A typical January is five degrees colder than December, but January 2020 was 0.8 degrees warmer - the 31st time January has been milder than December; the previous time it happened was during the winter of 2006.  Besides being slightly milder than December, its snowfall was a touch less as well (2.3" vs. 2.5").  Although the month had a minimal amount of snow, there have been 36 Januarys with smaller amounts.  

 

Three consecutive Saturdays had very different conditions:  Saturday, Jan. 11 had the mildest reading of the month (69°); Saturday, Jan. 18 had the biggest snowfall (2.1"); and Saturday, Jan. 25 had the biggest rainfall (0.85").

 

Mild weekend in january
Basking in the springlike temperatures of Jan. 11
 
Record mild weekend january 2020
Temperature map during the very mild weekend of Jan. 11-12

 

The month began with a continuation of a streak of above-average temperatures that began on Dec. 22 and continued thru Jan. 8.  This 18-day streak equaled the longest above-average streak of 2018-19, which happened at roughly the same time of the year (12/20-1/6).  Then, after one day with below average temperatures, there were seven more consecutive days with above average temperatures.  The entire 26-day period from 12/22 thru 1/15 was ten degrees above average.

 

A streak of six days in a row with mean temperatures ten degrees or more above average (Jan. 10-15) was closely followed by six consecutive days with lows in the 20s (Jan. 17-22).  Although this was far from frigid, it equaled last winter's longest streak with lows colder than 30°. 

 

January continued the pattern of one month wet, the next month dry, a trend that started in September.

 

Chart - 5-month precip trend sept 2019-jan 2020

 

Finally, this January missed being among the ten mildest January's by the smallest of margins as it was 0.08° degrees chillier than January 1880 (39.15° vs. 39.23°).  And although January 1880 had two days with lows in the teens (both were 17° readings) and its warmest temperature was four degrees cooler than this year, it had five more days with highs of 50°+ (14 vs. 9).  Both years had nearly identical snowfall (2.3" in 2020, 2.5" in 1880) and precipitation (1.93" in 2020, 2.02" in 1880).

 

Here are analyses of the previous six Januarys:

2019

2018

2017

2016

2015

2014


December 2019 Repeats December 2018's Wet Conditions

Dec 13 grand central wreath

 

December 2019 was the wettest month of the year and fifth wettest December on record (7.09" was measured).  Much of its precipitation fell in the first two weeks of the month.  In fact, the 5.05" that was measured during this period was the third greatest amount to fall in the first two weeks of any December.   Looking at temperature, the month was slightly above average (+0.8°).  Although Dec. 1-22 was 2.5 degrees colder than average, the rest of the month was mild enough (+9 degrees), to push the entire month into the above average column.  The mildest reading of the month was 58° (on 12/10), making this the first December since 2005 not to have any readings of 60° or warmer.  The coldest reading, 16° on 12/19, was three degrees colder than the typical coldest reading of December.  The 19th was also the only day that had a high of 32° or colder (25°).

 

Despite the month's surplus precipitation there were ten consecutive days with no measurable precipitation (Dec. 19-28).  This matched a 10-day stretch in September - the longest dry spells of the year.  (September 2019 had just 0.95" of rain, making it the eighth driest September on record).  Coincidentally, last year's wet December (ninth wettest) also had a ten-day stretch with no precipitation.

 

Being the wettest month of a year is rare for December.  Before 2019 only two other years had December as their wettest month - in 1957 (when 5.26" was reported) and in 1973 (9.98" was measured).  Another distinction for Dec. 2019 is that it was just the 13th month to have more than seven inches of rain as well as a streak of 10 or more days without any measurable precipitation.  (The longest streak during one of these months was thirteen days in June 2006).

 

Chart - 7 inches monthly rain

In addition to the soggy first two weeks, other December highlights included the season's first measurable snowfall on 12/2 (1.3" fell) and an out of the ordinary snow squall of 10-15 minutes during the afternoon of 12/18 that ushered in the coldest weather of December (0.4" accumulated, and an additional 0.3" fell from a snow shower a few hours later).  Additionally, the first four days of the month had highs/lows stuck in the 30s, just the sixth time there's been a streak of this length or longer.

 

Snow squall dec 19 2019

 

Finally, December 2018 and 2019 joined December 2008 and 2009 as the second pair of consecutive years to be among the ten wettest Decembers (2009 is #4; 2019 is #5; 2008 is #9; and 2018 is in tenth place). 

Previous December recaps:

2018

2017

2016

2015