August Feed

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

 

 


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

WaterskiingOn 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°+.

 

Hot weekend

 

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.

Chart - summer 1943 1944 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.

 

 Chart - 10 hottest mean temps in july

 

Chart - 10 hottest highs in july

 Scorching hot


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"


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

AugustAugust, 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

 

Aug 17 jefferson mkt

 

 


August 2018 Weather Recap: Unusually Wet, With Unusually Warm Nights

Summer downpourJuly's rainy and warm conditions carried over into August, which was even warmer and wetter, ending up as the ninth warmest August on record and the twelfth wettest.  It was 2.9 degrees above average and warmer than July (something that's happened in 22% of the years since records began in 1869).  Despite August being warmer than July (by 0.5 degrees), July's average high was slightly higher (84.9 vs 84.3); it was August's average low that made it warmer overall (72.0 vs. 70.4).  In terms of rainfall, August's 8.59" was about an inch more than what was measured in July (7.45"), with much of it falling during heavy downpours during thunderstorms.  Here are additional observations worth noting:

 

  • There were seven days in the 90s, which occurred during two heat waves - one was four days in length (8/5-8) and one lasted three days (8/28-30).  The four-day heat wave was one of the least impressive among those of this length. The hottest reading of the month was 94° on 8/28.  The coolest reading of the month, which was reported twice, was 65°, which tied August 2005 and 1906 for the mildest minimum temperature in the month of August.  The typical coolest low temperature in August is 59° (in the years since 1980).
  • This was the thirty-second warmest August in terms of average high, but it had the fourth warmest average low.  (The low was 4.2 degrees above average, the high was 1.7 degrees above.)  This produced the ninth warmest August overall (tied with Aug. 1955, which was even rainier than this August, with nearly eleven inches measured).  Three of the past four Augusts have now placed among the ten warmest.

 

Chart - warmest average lows in august

 

  • Twenty-three days had lows in the 70s, tying August 1980 and 2005 for the most in the month of August (the typical number of such days is 13).  The month's first 18 days all had lows in the 70s, only the second time it's occurred, joining August 1988.  It appeared the City was going to set an August record for most lows of 70 or warmer, but it was not to be as the mercury fell to 69° the evening of 8/31.  On 8/29 the low of 81° established a new record for the latest date for a low in the 80s, smashing the previous record by two weeks (which occurred in 1985 and 1988).  This summer was just the eighth in which both July and August had average lows above 70° (two of the other summers were in 2015 and 2016).
  • The month's diurnal variation (i.e., the difference between the high and low) was just 12.3 degrees, which was the smallest in August since 2000 (also 12.3 degrees).  The only variations smaller than this occurred more than 100 years ago, when eight Augusts in the years before 1911 had variances between 10.4 and 11.7 degrees (at the other end of the spectrum, the greatest diurnal variation in August is 20.4 degrees, which occurred in both 1964 and 1944.)
  • This year has had the twelfth wettest August, the fourth wettest July-August, and the twelfth wettest summer.  Almost all of July and August's rain fell in a soggy six-week period (July 12 - Aug. 22).  Ironically, while August is the year's wettest month (so far), it also had the longest streak with no measurable rainfall - eight days, from the 23rd to the 30th.

Chart - 10 wettest july-aug

  Storm approaches in august

 

Chart - 10 hottest augusts

Here are previous August recaps:

2017

2016

2015

 

 

 


Lackluster Heat Waves

LacklusterThis 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 66 four-day heat waves that have occurred since 1870 only one, in July 1896, had a lower average high, 90.3 degrees.  (2018's low-grade heat wave matched one in August 2009.)  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 degrees.)

 

 

 

Chart - 4-Day Heat Waves-Coolest + Hottest

 

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.)

 

Chart - coolest 4-day heat waves based on mean temp

 

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).  


August 2017 Weather Recap - Coolest Since 2008

August 2017After experiencing the third and fourth hottest Augusts on record in 2016 and 2015, August 2017 cooled down and was 1.2 degrees below average, making it the coolest/most refreshing since 2008 (and its average high was the coolest since 2004, at 1.7 degrees below average).  The month began on the hot side, with the only reading in the 90s, (a high of 92° on 8/1), but the rest of the month had twelve days with highs below 80° (the average number is seven).  Despite the cooler than average temperatures there were no lows in the 50s (but 8/30 had a low of 60° - and 9/1 a low of 55°).  Here are a few other interesting observations:

 

  • August 29, with a high/low of 68/62, was the first August day since 2010 to have a high cooler than 70°.
  • This was the first month this year with no days of rainfall of an inch or more.  (Through July there were twelve such rainy days.)  As a result, not surprisingly, the 3.34" of rain that fell was an inch below average.
  • This August joined August 2008 as the only two to have their one 90-degree day occur on 8/1.
  • If 8/1 ends up being the last 90-degree day of the year, it will be the earliest date for this occurrence since 1986 (when it happened on 7/26).
  • As for the summer, it came in just about at the average (-0.1 degree), with June 0.3 degrees above average, July at +0.6, and August -1.2.  This was the fourth summer in a row with no lows in the 50s during July and August, a record streak (by contrast, July/August 1962-1965 averaged nine days in the 50s).

 

End of summer

 

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save


Days of 95 Degrees+ and "Super" Heat Waves

Sweltering hotThe 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).

 

1955 chevy

 

  • 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°).

 

Nyc-heat-wave-1953

 

  • 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°.

 

106

 

  • 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).

 

Air condtioning

 

  • 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°.)

 

Excessive heat warning

 

 95+

 Summer beach scene in coney island

 Super Heat Waves

 

Super

   
(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.)

 

 

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save


The Towering Clouds& Beautiful Sunsets During Summer 2016

Sheridan sq sunsetI'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 ... 

 

 

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

 

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

 

Sunset in mckees rocks
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.

 

July 1 2016
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.

 

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

 

Towering thunderclouds in glen rock
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.

 

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

 

Sunset aug 3
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.

 

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

 

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

 

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

 

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

 

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

 

Puffy and wispy
Wispy and puffy clouds over the West Village.

 

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

 

Pastel sundown
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.

 

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

 

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

 

Sept14 sunset
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.

Save

 

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

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

 

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

 

Save

Save


August 2016 Passes August 2015 as Third Hottest

Third place Clipart_sweatingsunOne year after New York sweated through its third hottest August on record, August 2016 was a wee bit hotter, by 0.2 degrees.  This margin was due to warmer nights (71.8° vs. 71.0°) as the average high of 86.6° was a bit below last year's 86.9°.  And after July 2016 was the wettest in seven years, August reverted to the dryness of the first half of the year as its 1.97" made it the driest August in twenty years.  However, what August and July had in common were cool starts as July 1-4 was 3.6 degrees below average and Aug. 1-4 was 2.8 degrees cooler than average.  Another similarity was five-day heat waves (July 21-25 and Aug. 11-15), making this the first summer since 2002 to have two heat waves that were five days or longer. 

 

Here are  further details about August 2016: 

  • August had seven days in the 90s.  Interestingly, there have been twelve Augusts with ten or more 90-degree days, with all but one of them cooler than August 2016.  Why?  Like July, it was due to an absence of any sustained period of cool air.  The coolest high was 79° (on two dates), and the most below average day was just 3 degrees below average.  (August 2005, the second hottest on record, also had fewer than ten 90-degree days.)  In addition to the seven 90-degree days there were also five days with highs of 88° or 89° (all in the last two weeks).

 

Augusts 10 or More 90 Deg Days

  • Aug. 13, with a high of 96/81, was the hottest day of the year, passing July 23 and its high/low of 96/80.  However, when the heat indexes of each day are compared, the two days weren't close.  Aug. 13 was very humid and the heat index reached an unbearable 110° while July 23 had low humidity, which produced a heat index that was a few degrees below the air temperature.  For five consecutive days (Aug. 10-14) dew points never fell below 70°, and during those days heat indexes remained above 90° until nearly midnight.   
  • The 16-day streak of above average mean temperatures from Aug. 6-21 was the longest streak of the year.  Then two days after it ended a refreshing low of 61° was the "chilliest" reading since 6/18.  (Then unseasonably warm conditions returned for the final week of the month.)
  • A very fascinating thing happened on Aug. 25, when the year's total precipitation matched exactly the amount on that date last year - 26.92" (more than five inches below average).  And this continued for a few more days.
  • This August joined five others that were hot and dry.

 

Hot Dry Augusts

  • In the 12-day period from Aug. 11-22, measurable rain fell on ten of the days - but the amount that fell was a modest 1.90" (by contrast, a similar rainy stretch in the first half of Sept. 1974. saw 7.40" fall).  And much of the rain fell in just a half-hour period on Aug. 20 when 0.82" poured down during lunchtime - this was the same localized afternoon rainstorm that dumped three to five inches of rain on the north shore of Long Island.

 

Dry Rainy Periods

  • Both August 2016 and 2015 were hotter than July.  This was just the sixth time that back-to-back Augusts had this distinction.  And although the difference between August's and July's mean temperatures in 2016 and 2015 was minimal, this was because July of both years was well above average in temperature.

 

Aug Hotter Than July

  • Finally, July and August 2016 became the fifth hottest July-August combination on record, 0.1 degree ahead of July and August of 2015.  And this summer joined fourteen others that had two or more days with 80-degree lows, with one each in July and August.

 

Hottest JulyAug Combos

 

Hot forecast
The typical weather map in August 2016.


 

 

 

   

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save


Today in New York Weather History: August 27

 

1971

Rain from tropical storm Doria moved in shortly before daybreak and continued through early evening.  Rain fell heaviest between 1-3:00 PM when 1.76" came down.  In total, 4.16" was measured - a record for the date.  Wind gusts of 40-50 mph accompanied the rain.  A second round of rain would dump an additional 1.80" between 1-7:00 AM on Aug. 28.  Rainfall amounts were even greater in New Jersey and southeastern Pennsylvania. 

 

Tropical_storm_doria    

1980

It was hot, hot, HOT, with a blistering high of 97°, sixteen degrees above average.

1987

The 0.39" of rain that fell between 5-6:00 AM was the first measurable rain since Aug. 10.

1989

This was the sixth day this month with a low in the 50s, the most in August in the 1970-2020 period (later tied in 2007). 

1990

Today was the year's last 90-degree day, on par with the average date for this occurrence.  In total, the year had a dozen days in the 90s - well below the average of eighteen days.  Between Aug. 3 and today, twelve days had morning lows of 68° or 69°.

2003

Today's low of 72° was the last 70-degree low of the year, more than two weeks earlier than the average date of Sept. 11 - and just one day later than the earliest date for this occurrence (set in 1975 and later tied in 2009).   

2011

During the evening, wind and rain from Hurricane Irene began lashing the area as it slowly made its way northward from the North Carolina and Virginia coasts.  By midnight 2.88" of rain had fallen - with a lot more to come overnight.  As a precaution, New York's transportation system was shut down at noon and 350,000 residents were evacuated from low-lying areas.

 

HurricaneIrene

2012

In the late morning a quick-forming thunderstorm dumped a half-inch of rain in just 15 minutes, between 1:23-1:38 PM.

Save