July 2020 Is Seventh Hottest; Drought Eases Up

 

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.

 

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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).

 

 

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.)

 

 

Here are previous recaps of July from 2014 thru 2019:

July 2019

July 2018

July 2017

July 2016

July 2015

July 2014

 

 

A Look at New York City's Hottest Weekends of All Time

 

On the one hand, if you work a Monday-Friday schedule and have access to a beach or pool, a hot weekend can be delightful.  On the other, if you don't have access to a body of water hot weather can be brutal, especcially if you have outdoor plans or a wedding to attend.  This summer, the weekend of July 18-19 had highs/lows of 91°/72° and 94°/77°.  Hot, yes, but far from the most torrid weekends of all time in New York.  This analysis looks at conditions in two ways - by mean temperatures and by high temperatures.  In order to qualify, both Saturday and Sunday had to have highs in the 90s or hotter and lows in the 70s or warmer. 

 

Looking at mean temperature, the two hottest weekends were Aug. 13-14, 1988 (highs/lows of 96°/79° and 99°/80°) and Aug. 8-9, 1896 (95°/79°, 98°/82°).   Last summer (2019) had the third hottest weekend, with highs/lows on July 20-21 of 95°/82° on Saturday and 95°/80° on Sunday.  Focusing on high temperatures reveals that the five hottest weekends are different from the top-five based on mean temperature, with the hottest occurring on July 3-4, 1966 (highs of 100° and 103°), followed by July 20-21, 1991 (100° and 102°).  These are the only weekends in which both days saw highs in the triple digits; four other weekends had one day of 100°+.

 

 

And here are a few other findings of note. 

• The earliest and latest scorching hot weekends occurred in the same year - 1895 (in the before-air conditioning era).  On June 1-2 the highs/lows were 96°/77° and 96°/76°; on Sept. 21-22 the highs/lows were 95°/77° and 95°/75°. 
• Besides 1895, 1953 also had two sizzling weekends. The most consecutive summers with a hot weekend were in 1943, 1944 and 1945.

 

 

• The weekend of July 20-21 has been very hot in three summers: 1957, 1991 and 2019.
• Finally, the first weekend with lows in the 80s on both days occurred in 2019 (82° and 80°).  However, the weekend of July 23-24, 2011 had the warmest low of these select weekends - 83° on Saturday.

 

 

 

 

Here are other heat-related posts:

Revisiting New York's Hottest Summers

"Super" Heat Waves (95°+)

Hot, Wet New York Summer

Low Temperatures of 70° or Warmer

The Heat is On: New York's "Hell Week"

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

 

 

Lackluster Heat Waves

 

This post was inspired by this week's rather tepid four-day heat wave (Aug. 5-8, 2018), which had an average high of 90.8 degrees (with highs of 91°, 92°, 90° and 90°).  Of the close to 70 four-day heat waves that have occurred since 1870 (thru June 2021) only one, in July 1896, had a lower average high, 90.3 degrees.  (2018's low-grade heat wave matched one in August 2009 and would be matched again in June 2021.)  On average, four-day heat waves have had an average high close to 94°.  (The hottest four-day heat wave on record took place in the summer of 2010, when the high temperature from July 4-7 was 99.5°.)

 

However, the story changes when low temperatures are included in the analysis.  For example, this August's heat wave had an average low of 75.0 degrees, which was 1.3 degrees warmer than the average four-day streak and warmer than two-thirds of the four-day heat waves examined.  When combined with the average high, the mean temperature ranked as 27th coolest - quite a difference in ranking compared to its average high alone.  (This follows the weather storyline of this century, whereby nighttime temperatures in New York are warming more than daytime temperatures.)

 

 

Finally, while the typical four-day heat wave had a 20-degree difference between its high and low, this August's was 15.8 degrees apart, which was the third smallest diurnal variation of the heat waves studied (a heat wave in July 1995 had the smallest, 14.7 degrees, while the second smallest was in July 1870).  

July 2018 Weather Recap: Hot Temperatures, Followed by Torrents of Rain

 

If July 2018 were a cocktail its ingredients would be one part heat, three parts rain.  After a hot start, with temperatures nine degrees above average during the month's first five days (average high/low was 92°/78°), the rest of July was seasonably warm, which moderated the month's average temperature to 1.1 degree above average.  As for the rain, after a dry start, with just 0.24" measured through July 11, the skies opened up and the rest of the month was very rainy, with 7.21" measured.  With 7.45" in total this was the rainiest month in more than four years, since April 2014, and the rainiest July in fourteen (and the fourteenth wettest July on record).

 

In late July there were seven days in a row (July 21-27) in which measurable rain fell.  This was the fourth streak of six days or more this year, joining 1989 as the only two years since 1900 with four streaks of six days or longer.  (Besides the persistent rain, dew points throughout this week-long period were in the uncomfortable 72°-74° range.)

 

 

The seven-day streak with rain was the first since 2012, but this year's had considerably more rain (2.89" vs. 0.86").  The last streak of seven days or more with more rain was in May 2009, when 3.81" fell.

 

Downpours on 7/12 and 7/30 were confined to upper Manhattan; Central Park had 0.71" and 0.37", respectively, but my neighborhood, Greenwich Village, four miles south of the park, was dry.  And during the afternoon of 7/17 Manhattan was the bulls-eye for torrential rain from a severe thunderstorm, with 2.24" pouring down in little more than an hour.  Conversely, on 7/27 thunderstorms during late afternoon thru evening produced more than an inch of rain in most parts of the metro area (and 3-5" in parts of east-central NJ) but Central Park had only 0.25". 

 

July's rainfall in Central Park was considerably more than the three other reporting sites in the metro area:

 

Other July observations: 

• Four of the first five days in July had highs in the 90s; the only one that didn't was the 4th of July, but its high of 86° was the warmest reading on this holiday in five years.  However, due to its very warm low of 77°, the mean temperature was the warmest since 2010.

 

 

• Thirteen days in a row (July 8-20) had highs of 80° or warmer, the longest such streak since one of 19 days in August 2016.  (The record is 62 days in a row, set three years ago.)

• What was most impressive about the hot beginning to July were the low temperatures, all  which were 76° or warmer.  This happens almost as infrequently as five-day streaks with highs of 95°+.

• This was the ninth July in a row with no lows in the 50s, the longest such streak in the years since 1900.  Before 1980 more than half of Julys had at least one low in the 50s, but since 1980 that portion has fallen to 25%.

• By July 25 the month had picked up more rain than the combined amount in May and June (6.80" vs 6.64").

 

Here are links to previous July recaps:

2017

2016

2015

2014

 

July 2017 Weather Recap: Somewhat "Ho-Hum"

The month of July, temperature-wise, was close to average (+0.3 degree), with slightly below average rainfall (4.19", more than half which fell in the first week).  Thru 7/22 temperatures were 2.3 degrees above average, but the final nine days were four below average.  Five days had highs in the 90s, which was below the average of eight.  Four of these 90-degree days were consecutive, from 7/19 thru 7/22, making this the third heat wave of the year.  It was then immediately followed by five days in a row with highs in the 70s, the longest such streak in July since 2009.  7/20's high/low of 94/77 tied 6/13 as the hottest day of the year.  Finally, the month's rainfall highlight was on 7/7, when 1.78" fell, much of it pouring down during a two-hour deluge before lunchtime.  Here are a few other observations:

 

• July 4th was the warmest in four years, but its high of 85° was two degrees cooler than Easter Sunday's.  However, it started off much warmer, with a low of 70° versus Easter's morning low of 59°.  (And it was 24 degrees warmer than Memorial Day.)

• Although the average low for July was 1.0 degree above average, the average high was 0.4 degree below average.  This somewhat mirrored June, which had an average high that was 1.1 degree above average and a high that was right at the average.

• July's rainfall could have been considerably more but strong thunderstorms on 7/17 and 7/21 stayed north and south of Manhattan, and a predicted nor'easter on 7/29 stayed too far south and east of the City.

• This was the eighth July in a row with no lows in the 50s, continuing the longest such streak on record (for the month of July).

• July 1940, 1954 and 1963 had more than twice as many 90-degree days than July 2017, but their average temperatures were slightly lower, due to their average low temperatures, which were three degrees cooler:

 

 

• July Fun Fact: July 1937, 1938 and 1939 all had the same average temperature (76.6 degrees).  

 

 

 

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Days of 95 Degrees+ and "Super" Heat Waves

 

The majority of days with highs of 90° or hotter in New York fall in the 90-92 range (56% to be exact).  And while the average number of 90-degree days each year is eighteen (including readings in the triple digits), the average number of readings that reach 95° or higher is just three (and about one out of every four years have had no highs that hot, the most recent being the summer of 2017).  The most in one year was sixteen, in 1955.  What follows are some more hot-Hot-HOT weather observations, best read in a well air-conditioned environment:  

• Eleven years (since 1872) have had ten or more days with readings of 95°+, with the most recent being 2002, which had 13.

• Although 1955 is the year with the most days with highs of 95° or hotter, it ranks 19th in total number of 90-degree days (with 25).  Incredibly, nearly two-thirds of its 90°+ days were 95°+ (the average is one-in-six).

 

 

• 1970 has the distinction of having the most 90-degree days, twenty-two, without any being 95° or hotter.  And not far behind are 1959, which had just one of twenty-seven days reaching 95/100+, and 1939, which had one of twenty-four.  The most consecutive years with no days of 95°+ is two, which has happened four times, most recently in 2003 and 2004.

• The greatest concentration of years with with well above-average number of days with 95°+ readings was 1952-1955, when there were nine in 1952, twelve in 1953 and sixteen in 1955 (1954 had four, two of which were highs of 100°).

 

 

• Although 1917 had only six days in the 90s/100s, the last four, on consecutive days, were sizzlers, with highs of 98°-100°-98°-98°. 

• The earliest excessively hot days occurred on April 18, 1976 and April 17, 2002, both which had highs of 96°, and on May 19, 1962 when the temperature topped out at a blistering 99°.  On the late side, the high reached 99° twice on Sept. 11, in 1931 and in 1983; and on Sept. 23, 1895 the high was 97°.

• The most consecutive days with highs of 95° or hotter ("super" heat waves) is eight, in 1944.  There has also been a streak of six days (in 1953) and seven that were five days in a row.  The last time we experienced a "super" heat wave of five days or longer was during the summer of 2002 (which is the only one among the eight lengthiest to have no highs in the triple digits).

• The hottest temperature ever recorded in New York, 106° on July 9, 1936, came in the middle of a three-day super heat wave, with the day before having a high of 97° and the day after, 102°.

 

 

• The hottest early "super" heat wave occurred in 1925 when highs of 99°-99°-98°-96° were experienced from June 4 to June 7.  The latest was in 1895 when there was a streak of three days from Sept. 21 to 23 (95°-95°-97°).

• In 1944, which had thirty-seven 90-degree days, the first twenty-four were below 95°, but then 11 of the next 13 were 95° or hotter (concentrated in the four weeks between Aug. 4 and Sept 2).

• Perhaps the most famous super heat wave was July 1977's, which coincided with New York's infamous blackout.  However, although the blackout began on the first day of a nine-day heat wave, the five days in a row with highs of 95+ began the day after power was restored: 98°-98°-97°-100°-102° (July 15-19).  And after a one-day respite on the 20th (high of 92°) the next day's high jumped to 104°.  

• In less than six weeks in the summer of 1949 (July 3-Aug. 11) there were three three-day super heat waves: 99°-102°-95° (July 3-5); 97°-99°-95° (July 28-30); and 100°-98°-99° (Aug. 9-11).

 

 

• Finally, the hottest super heat wave of four days or more was in 1993 when the five days from July 7-11 averaged 99.8°, with highs of 98°-100°-101°-102°-97°.  Two years earlier there was another streak of five days in a row, from July 17-21: 96°-99°-96°-100°-102°.  Then after a one-day break, when the high "cooled" to the upper 80s, the high on 7/23 was 99°.   (A three-day "super" heat wave on July 1-3, 1966 had an average high of 100.3°.)

 

 

 

 

 

 

   
(I owe a debt of gratitude to Eugene DeMarco, a follower of NYC Weather Archive, whose spreadsheet showing the 90-degree days of every year, made this analysis so much easier for me to do.)

 

 

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The Towering Clouds& Beautiful Sunsets During Summer 2016

I've always had an appreciation for clouds and sunsets.  Five years ago I probably wouldn't have been able to write this post because I didn't have my smartphone with its camera.  Now I'm able to snap photos at a moments notice, enabling me to capture this summer's overabundance of photo-ready thunderheads and stunning sunsets.  And because I live in the West Village I probably notice them more since the low-rise buildings make the sky much more accessible than in Midtown Manhattan.  I hope you enjoy the photo revue that follows ... 

 

 

The photo display begins with one of me along the Westside Highway at dusk during Memorial Day weekend.

 

Rays of the setting sun stream over Sheridan Square in Greenwich Village.

 

I took this photo during a June visit to Pittsburgh to see my mother. These clouds brought to mind those I'd often see over the Atlantic Ocean close to sundown on Fire Island.

 

Taken on July 1, this photo shows a thundercloud from a storm that struck half an hour earlier. Although it was around 9PM the top of the cloud was catching the rays of sun that was below the horizon.

 

Early evening sun filtered through a slate gray sky over Sheridan Square.

 

This isn't a cloud formation in New York but it deserves an honorable mention.  I snapped the photo of this breathtaking thunderhead during a weekend visit to south central Pennsylvania in the midst of a late July heat wave.

 

Taken from my kitchen looking east as the full moon was rising.

 

This was the view on 7/28 looking east from the 44th floor of an apartment building on the  Upper West Side. The light pastel coloring was the result of a fire in a warehouse in Long Island City (Queens) an hour earlier.

 

Taken as I was walking to the subway after work on 42nd St. across from across from Grand Central Terminal.

 

Looking west from Sheridan Square at around 6PM in mid-August. Seeing it I felt I was in the presence of the Divine.

 

Early evening on a hot day in mid-August.  These mountainous clouds brought a quick downpour to upper Manhattan, but not to Greenwich Village.

 

Similar view and thunderclouds as the previous photo but on a different day one month later.

 

The same cloud formation as it moved behind the apartment building at 10 Charles St.

 

Wispy and puffy clouds over the West Village.

 

Sunset on the Saturday of Labor Day weekend, taken on Christopher St. pier, which looks out across the Hudson River.

 

This is how the sun's rays from the above sunset reflected on the bank of towering clouds in the east.  Reminds me of rainbow sherbet.

 

I snapped this photo shortly after I came out of the Christopher St. subway station in the early evening. This view is looking east.

 

Taken the evening of Sept. 11 as I left the gym on Seventh Ave. South.

 

Taken on Sept. 14 close to the West Side Highway in Chelsea, shortly after a late afternoon thunderstorm. A few hours earlier the temperature was in the low 90s, the last 90-degree day of the year.

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6PM on Sept. 15, awaiting take-off at LaGuardia Airport.

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Finally, a golden sunset on Sept. 17 during a visit to my childhood neighborhood in McKees Rocks, PA.

 

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July 2016 Weather Recap - A Month in the Tropics

As we entered the last week of July it appeared the month's headline story would be about the heat, which took hold in the second half of the month.  But when three one-inch rainstorms occurred in the last week, the month's storyline became the combination of heat and rain.  A hot July is usually on the dry side (with rainfall about 30% below average), while a rainy July is cooler than average (by one or two degrees).  July 2016, however, was an anomaly in that it was the 21st wettest and 22nd hottest (going back to 1870). 

 

WELCOME RAINFALL

The 7.02" of rain measured in Central Park made July the rainiest month since April 2014.  It was also the wettest July since 2009.  Additionally, the month's rainfall was more than what fell in the previous twelve weeks (since April 10).  Finally, only one July has been hotter and wetter than this July - July 1988, which had 8.14" of rain and was 2.7 degrees hotter than average (see chart at bottom of page).  In addition to the three one-inch rainfalls at the end of the month, a rainstorm that began the night of July 4th (after the Macy's fireworks exhibition had ended) and lasted through the next morning also delivered more than an inch.  And while this rain helped reduce the year's rain deficit (which was also an issue last year), it was still four inches below average at the end of the month (13% below average).

 

HOT, BUT DON'T BELIEVE THE HYPE

The month began with three days in a row with highs in the pleasant 70s, the first time since July 1960 that the month started this way.  Then from July 14-30 the average high/low was 90/73, 4.5 degrees above average.  And fifteen days between July 6-29 had highs of 88° or hotter.  Additionally, eight days had lows of 75° or warmer, with the warmest being 80°.

 

 

After having no 90-degree days in June, July had ten (the average is eight), with seven occurring in an eight-day span from 7/21-28.  The one day that didn't reach 90° had a high of 89°.  If the temperature had reached 90° on that day (as it did at Newark and LaGuardia Airports) we  would have had an eight-day heat wave, which would have been the longest since 2002.)  The hottest day of the month was July 23, with a high/low of 96/80, eleven degrees above average.  However, July 25, with a high of 93°, felt hotter because it was much more humid and the heat index reached 102° (the feel-like temperature on the 23rd was actually 94° because of low humidity.) 

And while the second half of the month was hot and sultry, it was over-hyped by the media and some meteorologists, who put a sinister spin on the term "heat dome", leaning heavily on the global warming angle.  (I was interviewed on TV about the heat wave and I played it down as nothing extraordinary, especially compared to truly brutal heat waves of the past.)

 

 

CLOUD-COVER CURIOSITY

Despite all of the rain, the month was very sunny.  On the National Weather Servce's scale of cloud-cover, where zero is clear skies and ten is overcast, the month averaged a 2.8, with 19 days having clear or sunny days (a rating of zero to 2).  However, what's peculiar is that Newark and LaGuardia were much cloudier (6.3), but hotter.  JFK Airport also had a 6.3 but with slightly lower temperatures than Central Park.  Is this reality or is there a difference in the way Central Park scales cloud cover?  It seems counter intuitive that Newark and LGA, with so much cloud cover, would have 15 and 16 90-degree days, respectively, while sunny Central Park had "just" 10 hot days.  Another peculiarity is the fact that Central Park reported no thunderstorms in July but JFK and Newark had seven and LGA four.  Working in Midtown Manhattan, I heard thunder and saw lightning during a number of storms so I'm baffled by this.

 

 

Finally, despite how warm the month was (2.2 degrees above average), four other Julys since 2010 were hotter:  2015, 2013, 2011 and 2010.  And although July of last year was 0.1 degree hotter, this July had twice as many days in the 90s.

 

 

 

 

 

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The Summer of 1908's Puzzling Nighttime 'Heat Bubble'

 

Reviewing New York's weather statistics over the past 145 years reveals that the years before 1930 were noticeably cooler than the years that followed (especially after 1980), which have seen some of the warmest years on record.  But, curiously, a number of the summers during the first decade of the 20th century had uncharacteristically warm nights, in particular, 1908.  That year stands out for a seven-week period with unusually warm nighttime temperatures unlike any that have been experienced - even in recent years.  Although highs during those weeks were three or four degrees above average, the average low of 74.5° was eight degrees above average.  Between June 30 and Aug. 17, fifteen days had lows of 77° or warmer, eight of them of 80°+.  No other summer has had that many sultry low temperatures.  It was these lows that made July the warmest on record until 1952. 

 

Sultry low temperatures became more common after 1990, but not during the first half of the 20th century.  In addition, the diurnal variation in the summer of 1908 was very narrow, with high and lows on many days ten degrees apart or less (typical is about sixteen degrees).  What was it about the air masses or jet stream in July 1908 that prevented temperatures from cooling down after dark?  Was it a matter of air pollution/particles of soot that prevented the temperature from falling at night?  This holding onto daytime heat is a characteristic of global warming experienced during the 21st century, but one hundred years ago it was unheard of.

 

 

The chart below compares July 1908's average high/low temperature to those of eighteen other hot Julys.  What it shows is that the average highs of these hot months were two or three degrees warmer than July 1908, but July 1908's average low was warmer than every hot July by that same margin, with the exception of July 2013, which had the same sultry low.

 

 

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