New York City Weather Archive

May 2020 Weather Recap - Chilly & Dry

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.

 

 

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 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 to have no days with 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.

 

 

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°).

 

 

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".

 

Here are April recaps of previous years:

2019

2018

2017

2016

 

     

February 2020 Weather Recap - Mild & Snow-Free

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.

 

(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

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").

 

Basking in the springlike temperatures of Jan. 11

 

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.

 

 

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

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).

 

 

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.

 

 

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

 

Previous December recaps:

2018

2017

2016

2015

 

 

November 2019 - Cold & Dry

November 2019 was the 31st coldest November and 32nd driest (going back to 1869).  It tied November 2012 as coldest November of this century.  Nine days had lows of 32° or colder, the most since 2013 and well above the 21st century average of three.  Looking at precipitation, the first 17 days of the month had just 0.25" of rain.  1.95" was measured for the entire month (more than two inches below average), with much of the rain concentrated during the seven days between 11/18-24.  Despite the cold temperatures no snow fell.  Other interesting aspects:

 

• The 11-day period between 11/8-18 was ten degrees below average (six days had mean temperatures that were 10-20 degrees below average).  The month's other nineteen days had temperatures that were close to average, resulting in the month being 3.8 degrees colder than average overall (its average low was 4.5 degrees below average).  This was the most below average of any month since March 2015 (-4.4 degrees).

• Half of the Novembers that were colder than Nov. 2019 occurred in the 19th century (1869-1899).  Looking at the past 100 years Nov. 2019 tied for ninth coldest.

• The mildest reading of the month was 71° in the early hours of 11/1; the coldest reading was 23° on 11/13.  That reading was a record for the date and followed a record low of 25° the day before that. 

• Since 1970 November's mildest reading has averaged 71°, which was the same as this November.  However, the second mildest reading has averaged 69°, but this year's was only 62°, which was the chilliest second mildest reading since November 1977.

• Gusty winds on Thanksgiving Day somewhat marred Macy's Thanksgiving Day Parade.  Up until a few hours before the parade started it was uncertain whether its famous balloons would be permitted to float high above the streets of Midtown Manhattan, but it was decided to let them participate at a much lower height than usual.  Wind was the only issue as temperatures were at seasonable levels and there was no rain.

 

 

• On 11/13 the relative humidity at mid-day fell to an exceptionally low 13%, the lowest humidity reported in November in the years of the 21st century.  It was also the only date outside of March and April with a humidity level this low.

• Last November, 3.3 degrees colder than average, seemed more wintry than this November because it featured a 6.4" snowstorm and had one of the coldest readings ever reported in November, 15°.  It also was one of the wettest Novembers.  While its average high was 0.9 degree colder than this November, it's average low was 1.9 degrees milder.  Like Nov. 2019, the equally cold Nov. 2012 was dry (1.81").  However, a big difference was that Nov. 2012 had a snowfall of 4.7" on 11/7-8 (the earliest accumulation of four inches or more).

 

 

Other November recaps:

2018

2017

2016

2015

 

 

 

 

A Reading in the 90s Makes October 2019 Memorable in New York

Although above average rainfall characterized October 2019, a day of sizzling heat at the beginning of the month is likely what many New Yorkers will remember.  After having no days in the 90s in September, the high on 10/2 was a torrid 93°, 24 degrees above average - and the first 90-degree reading in October since 1941.  (The high the next day, however, was thirty degrees chillier.)  As for the rain, 6.15" was measured, the most in October since 2006, and the second rainiest month of the year (May had 6.77").  A little more than half of the month's rain fell on two days: on 10/16, when 1.83" fell, and 10/27 (1.38").

 

The month was three degrees warmer than average and was the 24th mildest October on record (but it ranked 12th for average low).  And although it had just a few days with highs of 70° or warmer or lows in the 60s, the month also had very few days with highs in the 50s or lows in the 40s (the chilliest reading was 43° on the 19th).  Similar to September, October ended with 11 days in a row with above average readings (averaging six degrees above average).  Temperatures between 10/3-20 were average while the other 13 days of the month were seven degrees above average.

 

In the years since 1900 three out of four Octobers have had their chilliest readings in the 30s or 20s.  October 2019 joined only five other Octobers whose chilliest lows were 43° or milder.  (The mildest reading to be the chilliest October low is 45°, which happened in 1945 and again in 1971.)  The typical chilliest October temperature is around 38° (fourteen Octobers since 1900 had chilliest readings of 32° or colder; the last time it occurred was in 1988).

 

 

The low on Halloween was 60°, 15 degrees above average.  It joined 10/1 and 10/2 as the only days in October with lows in the 60s.  The high of 71° on 10/31 was the warmest reading on the holiday in ten years, when the high was also 71°.  It was also the mildest reading since 10/14.  (And although 10/31's high of 71° was 22 degrees cooler than 10/2's, its low was just three degrees lower.)

 

 

Finally, October's plentiful rainfall followed a very dry September, in which just 0.95" was measured.  And while this was a decided contrast, it wasn't nearly as extreme as Sept/Oct 2005 when  October saw 16.73" after a paltry 0.48"; April/May 2007, when April had 13.05" and May had just 1.88"; and Aug/Sept 1882, when September had 16.85" and August only 1.14".

Here are links to other October recaps:

2018

2017

2016

 

 

 

September 2019 - One of 10 Driest Septembers On Record

September 2019 was the first month since October 2013 to have less than an inch of rain; it was the eighth driest September on record (0.95" was measured).  Thru 9/20 the month had average temperatures; then the last ten days were eight degrees warmer than average, resulting in the month being 2.4 degrees above average (24th warmest since 1869).  Although it was warmer than average, the month had just one low of 70º+, the fewest in September in ten years (there were none in 2009).  It was also the first September since 2011 not to have any highs of 90° or hotter. 

 

This September added to the record set last year when last September was the fourth in a row with an average temperature of 70.0 degrees or warmer.  September 2019, however, was the "coolest" of the five.  However, a record that was tied last September, the sixth September in a row with a high in the 90s, wasn't broken this year as the hottest temperature this September was 89°.  (It occurred on 9/23 - the same date as the month's only low in the 70s).

 

 

Two-thirds of September's paltry amount of rain fell in the first six days of the month, split mostly between Labor Day (when 0.30" fell mid-day, the most to fall on the holiday in sixteen years) and 9/6, when the most northernmost band of hurricane Dorian dropped 0.27" in less than an hour during mid-afternoon.

 

 

Finally, humidity of 15% or lower occurs very infrequently in New York, and when it has happened it's been confined to March and April (in the years since 2000) - until 9/19, when it dropped to 15% for a few hours that afternoon.  The last time the humidity was this low in September was on Sept. 11, 2001, when it bottomed out at 16%.

 

Here are recaps of the five previous Septembers:

2018

2017

2016

2015

2014

 

 

 

 

One Word Sums Up New York's Weather in August 2019: 'Uninspiring'

August, much like June, had close to average temperatures (+0.3 degrees).  Perhaps the most interesting story during this month of uneventful conditions was the twelve-day period from Aug. 17 thru 28 in which the first six days were very warm (average high/low of 89°/73°, including the month's three days in the 90s) followed by six days that were pleasantly cool (high/low of 75°/64°).  The month's three days in the 90s went no higher than 90° (something which has occurred just once before, in August 2014).  Finally, this was the sixth consecutive August with no readings in the 50s.

 

The month had somewhat below average rainfall.  The 3.70" that was measured was the least precipitation since February's 3.14".  Much of it fell on three days: 1.18" on 8/7, 0.64" on 8/18 and 1.01" on 8/22.  (Although August 2019 had less than average rainfall there were six drier Augusts in the 2010s.)  There were ten thunderstorms or brief periods of heavy rain in the three weeks between 8/3 and 8/22.  They occurred mostly in the afternoon and evening and were responsible for the day's lows occurring in the evening rather than at around daybreak.  Without these cool downs there would have been five days with lows of 75° or warmer rather than one.

 

Here are recaps of the four previous Augusts:

2018

2017

2016

2015

 

 

 

 

Cooling Thunderstorms Prevented July 2019 From Ranking Among 10 Hottest Julys

As July 2019 came to a close it appeared the month was about to join three other Julys from the 2010s ranked among New York's ten hottest Julys.  As late as 3:00 PM on 7/31 the day's high/low was 87°/76°, and if that low temperature held  the month would have tied July 1966 as ninth hottest (both with average temperatures of 79.66°).  But then mid-afternoon thunderstorms erupted between 3-4:30 and the temperature tumbled to 70° - making it the day's new low.  This brought July 2019's average temperature down to 79.56°, pushing it to eleventh place, 0.05 degree cooler than July 1949 (79.56° vs 79.61°).  However, as a consolation prize, July 2019's average low was warm enough for it to rank fifth in this category. 

 

Other observations:

• Besides the thunderstorms of 7/31, thunderstorms on 7/17 and 7/22 also resulted in lows that occurred in the evening.  Much of the month's rain fell from these two rainstorms, with 2.33" falling on 7/17-18 and 2.19" on 7/22-23.  So far this year these are 2019's two biggest 24-hour rainfalls.  And with 5.77" measured July 2019 became the second rainiest of the fifteen hottest Julys.  This was after just 0.08" of rain fell in the first ten days of the month.  (Last July, which had nearly seven-and-a-half inches of rain, also started out dry, with just 0.24" measured in the first eleven days of the month.)

 

 

• There were ten days in July with highs of 90°+ (average is eight), making it the sixth July of the decade to have this many, the most of any decade.

 

 

• This July joined 36 others that have had ten or more days with highs of 90°+.  However, July 2019's ten torrid days had the "coolest" average temperature, tied with July 1887 (91.7°).  July's hottest temperature, 95° on 7/20 and 7/21, was one of the coolest readings for hottest temperature among the Julys with ten or more 90°+ days; those other months' hottest readings averaged 99.4° (half of them had hottest readings in the triple digits).  But the average low on July 2019's hot days, 74.9°, was warmer than 24 of the 36 other Julys. 

• July 1's low of 65° was the "coolest" reading of the month.  Only July 2008 has had a warmer "coolest" reading (66° on three dates).  The month had two days with lows in the 80s, which were the same two days that had highs of 95°.  It joined ten other Julys with two or more lows in the 80s.  Lastly, this was the unprecedented tenth year in a row in which July had no readings in the 50s.

• What was notable about July 2019 was its consistent warmth but absence of extreme heat (excluding heat indexes).  26 days had highs of 85° or warmer, one shy of the July record, which has happened in three years: 1944, 1966 and 1993 (the average number of such days is 17).  Additionally, 24 days had lows of 70° or warmer, the second most on record; only July 2010 had more, with 25 (the July average is 15).

• I refer to the week of 7/16 as as New York's "Hell Week" because, historically, it is the week most likely to have readings of 90° or hotter.  And this year six of July's ten 90-degree highs were concentrated during this week.  The one day not in the 90s, 7/18, was stuck in the 70s all day (high/low of 79/71) due to overcast skies and northeasterly winds.  Ironically, 7/18 has been the date most likely to have a high in the 90s/100s.

 

 

• July was the third month in a row with more than five inches of rain, joining three other years which had five or more inches in May, June and July (1984, 1989 and 2009).  Although the 18.05" that was measured was nearly five inches above average it was significantly less than what fell in the other three years.

 

• Finally, for the fifth year in a row 4th of July had a warmer high than the previous year.  And with a high of 90°, this year's was the hottest 7/4 since 2012.

 

Here are recaps for the five previous Julys:

July 2018

July 2017

July 2016

July 2015

July 2014