New York City Weather Archive

July 2024 Weather Recap: Hot First Half, Seasonable Second Half

During the first half of July 2024 it appeared the month might become one of the three hottest Julys on record. Between July 1-17 the average temperature was four degrees above average, with nine days reporting highs in the 90s and seven days with lows of 75° or warmer. Then the weather pattern shifted and the last two weeks of the month cooled down to seasonable readings, and the month entered the record books tied for 11th hottest with July 1949 (2.1 degrees warmer than average).

This July was just the fourth month on record to have no high temperatures cooler than 80° (the average number is six). And its 24 days with lows of 70° or warmer was the third most of any July (tied with nine other Julys, including 2023 and 2022).

The hottest periods of July were July 4-11 (with every day having a high of 89° or hotter) and July 14-17 (every day in the 90s); both periods had the same average high/low of 91°/75°, six degrees above average. (The month’s other 19 days had an average high/low of 84°/70°.) The hottest reading of the month was 95° on 7/8, the warmest low was 79° on 7/7.

The last of the month's nine days in the 90s was on 7/17. At that point, Central Park had experienced 15 days of 90+ for the year (all of the them between 6/20 and 7/17), which was the 14^th most on record by that date (going back to 1869).

Going into the evening of 7/31, it appeared the month would be the 10^th hottest July on record. However, a brief shower at 9:30 cooled the temperature from 88° to 73°, which was five degrees below the morning’s low of 78°. This change was enough to knock it out of 10^th place (behind July 1966).

July's coolest temperature was 64°, which was reported on 7/1. Only six Julys have had a milder reading for their coolest temperature (eight others also had 64° as their coolest reading).

As for rainfall, all but 0.39” of the month’s 4.20” fell during the week of 7/11-17. July’s total rainfall was slightly below average (by 0.40”) and was the driest July since 2017 (which had 4.19”). By contrast, the Julys between 2018-2023 averaged 6.60” of rain. Most of this July’s rain came from two storm systems that were five days apart as 2.06” fell on 7/13 and 1.46” fell on 7/17.

Although July's rank for average temperature was 11th, for average low (72.1°) it ranked sixth, but for average high (87.2°) it ranked 17th.

Finally, while Central Park and LaGuardia Airport both had nine days with highs of 90+, Newark had 14, but JFK had just one (on the last day of the month). Looking at highs of 88+, the four sites reported 20, 16, 12, and one, respectively. JFK isn't usually so different from the other stations, but this July regularly had winds from out of the south, off the ocean, which had a moderating effect on the daytime temperatures at JFK.

Here are recaps of previous Julys:

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Tags: New York City's weather in July 2024

July 2023 Weather Recap: Consistently Warm Rather Than Excessively Hot

This post may be one of the few weather-related articles that doesn't hyperventilate about hot weather in the middle of summer. And despite New York's news media hyping the term "heat dome" any time the local forecast called for a high approaching 90°, just five days in July had highs in the 90s in NYC, and there were no heat waves; the hottest reading was just 93°. Globally, July was the hottest month on record, but that wasn't the case in Central Park as it was the 20th warmest July (average high/low was 86.4°/71.7°, 1.5 degrees above average).

Every day but one had a high of 80° or warmer (the typical number of days in July with highs cooler than 80° is six), comparable to last July which had no such days. As for low temperatures, this July and July 2022 both reported 24 days with lows in the 70s, tying three other Julys for third most (July 2020 had 26, 2010 had 25). Although it had a below average number of days in the 90s (five versus seven), July 2023 had an above average concentration of highs that were 88° or 89°, with ten counted.

July was slightly wetter than average, with 5.34" measured. This was almost double the amount that fell in May and June combined (which had 1.29" and 1.62", respectively). More rain fell in the first four days of July (1.66") than what fell in all of June. This included 0.63" of rain that fell on 7/4, the most on Independence Day since 1981 (when 1.76" fell).

The month's greatest daily rainfall was 1.32" on 7/16 (0.91" of it fell between 11 AM and 1 PM); this daily total was more than what fell in all of April. On that day, which had a low of 74°, the high reached just 78°, which is the coolest high temperature ever reported with a low this warm.

Only five days had below average temperatures, all of which occurred in the second half of the month. Meanwhile, seven days were five or more degrees above average.

July's temperature range was only 27 degrees, from 66° to 93°. This compares to an average range of 34 degrees (62° to 96°). Only one other July has had a smaller range (2004's 24-degree range).

Although there were no heat waves, there was a streak of eight days with highs of 85° or warmer (July 22-29). Finally, high dew points were a consistent feature of July as two-thirds of the days in July experienced dew points of 70° or warmer, giving the air an uncomfortable, tropical feel.

Here are July recaps from previous years:

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July 2022 - Just The Second July With Highs of 80+ On Every Day

A typical July in New York has six days with highs cooler than 80°. However, July 2022 had no such readings and joined July 1944 as the only other July in which every day had a high of 80° or warmer (it also happened in August 2015). The coolest high was 81°, which occurred twice. Overall, July 2022 was two degrees warmer than average (high/low of 87.3°/71.8°) and ranks as the 13th hottest July on record; it had the 8th warmest low, and tied for 16th warmest high.

The number of days with highs of 85° or warmer was 25. Only five other Julys have had more (in 2019, 2010, 1993, 1966, and 1944) and four others have had 25. The hottest reading was 95°, which occurred on three days, and the warmest low was 79°. Of the ten Julys with 25+ days of 85+, July 2022 had the fewest days of 87+ as it had 10 highs of 85° (7) and 86° (3).

The coolest low was 65° on the Fourth of July. Only five other Julys have had a chilliest low this mild or milder (the most recent was two years ago when the coolest low of 67° was the mildest coolest July reading on record).

During the first half of the month it appeared July's big story would be the very dry conditions as just 0.33" of rain was measured in Central Park through 7/15 - the least to fall in the first half of July since July 2002. And while a large portion of the metro area continued to suffer through dry conditions in the second half of the month (Newark's July total was just 0.55", JFK's was 1.10"), 4.22" fell in Central Park, which was double the typical amount. As a result, July's total rainfall ended up being very close to average (0.05" below). Much of the rain fell from isolated strong thunderstorms. The most to fall on one day, 1.85" on 7/18, was a record for the date.

A six-day heat wave, from 7/19-24, was the longest since the summer of 2013. The average high/low was 94°/77°. In addition to these six days, there were four other days with highs in the 90s (on 7/1 and 7/12-14); the total of 10 was three more than average. The hottest day of the month occurred on the last day of the heat wave, with a high of 95°/79°. Two other days during the heat wave, 7/20 and 7/23, had highs/lows of 95°/78°. (In addition to the large disparity in rain compared to Central Park, Newark also had a reecord-setting five-day streak of triple-digit highs).

Typically, June averages six lows in the 70s/80s and July averages 16. This summer the respective numbers were one and twenty-four. This increase of 23 days compared to June is the greatest increase from any June with 0, 1 , or 2 lows in the 70s. Only July 2020 and 2010 have had more lows in the 70s/80s than July 2022 (tied with three other years that had 24 such lows).

Finally, the 4.55" of rain that fell was the eighth time this amount was a monthly precipitation total. The most recent occurrence was in April 2019, and there was another July with this amount in 1916.

Here are July recaps from previous years:

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July 2021 - Third Rainiest July Keeps Mid-Summer Heat in Check

With 11.09" of rain measured in Central Park, July 2021 became the third rainiest July on record (behind 1889 and 1975), and 15th wettest month overall. This was New York's first month with ten inches or more of precipitation since June 2013 (10.10"), and the most to fall in any month since August 2011, when 18.95" flooded the City (the greatest monthly amount on record).

A little more than half of July's rain fell on three days between July 8-12: 2.27" on 7/8; 2.06" on 7/9, and 1.42" on 7/12. The amounts of 7/8 and 7/9 set records for the dates. 8.49" of rain fell in the first 12 days of the month (and 9.14" if 6/30 is included), then 2.60" fell thereafter (which was slightly below average for that period).

There were 18 days of measurable rain, which was the second greatest number of days with rain in July. July 1871 had twenty days, but just half the amount of rain as July 2021. (Of the 27 months with ten inches or more or precipitation, the average number of days of measurable precipitation is 13.)

Besides being rainy, this was the coolest July since 2009 (and 0.1 degree cooler than July 2014). When all Julys are considered, July 2021 is in the middle of the pack, temperature-wise, with 54% being warmer. The combination of a warmer than average June (+2.3 degrees), and July being 1.5 degrees cooler than average, placed these two months closer together (1.7 degrees) than any June/July combo since the summer of 2001 (when July was just 0.3 degree warmer). Looking at average high and low, July's average high of 83.0 was just 0.5 degree warmer than June's, while the low of 69.0 was 3.0 degrees milder. Because many days had dew points in the 68°-73° range, the air often felt oppressive rather than cool.

For the first time since 2009, a reading in the 50s occurred in July - 59° on 7/3. And on 7/3, the high was only 66°, which was the first high cooler than 70°in July since 2013, and the coolest reading in July since 2005 . The month's coolest and hottest readings were three days apart as a high of 92° occurred on 7/6 (and the 59° reading came three days after June's hottest temperature, 98°, on 6/30).

July had four days in the 90s, half as many as June, and the fewest such days in July since 2014, which had three. (Seven of the Julys between 2000-2009 also had four or fewer days in the 90s.) Although the number of days of 90+ was half the average for July, the number of lows in the 70s, 16, was an average am0unt (but ten fewer than last year's record amount).

July had 8.47" more rain than June's 2.62", but there have been ten other instances where the disparity between two months was even greater (looking only at wet months preceded by dry ones). The greatest difference occurred in Sept-Oct 2005, when October had 16.73", which was 16.25" more than September's bone-dry 0.48".

Finally, after suffering through sweltering heat, and a nighttime thunderstorm on the last day of June, the last day of July couldn't have been more different, as skies were clear and temperatures on the cool side (high/low of 77°/60°). While 6/30's high of 98° (14 degrees above average) was the hottest reading on that date since 1964, 7/31's low of 60° (ten degrees below average) was the chilliest since 1956.

Here are other July recaps:

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Tags: New York weather in July 2021, very rainy July 2021

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:

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Tags: July 2020's weather in New York

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, especially 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 second 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°. The earliest torrid weekend, in 1987, occurred two days earlier than 1895's, on 5/30 and 5/31 (with highs/lows of 97°/74° and 94°/76°).
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"

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Tags: hot weekends, hot weekends in New York City, hottest weekends

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:

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Tags: days with highs of 85 degrees or warmer, July 2019 weather in New York, rainy Julys in New York, Review of July 2019's weather

Lackluster Heat Waves

This post was inspired by the rather tepid four-day heat wave of Aug. 5-8, 2018, which had an average high of 90.8° (with highs of 91°, 92°, 90° and 90°). Of the close to 70 four-day heat waves that have occurred since 1870 (thru June 2023) only one, in July 1896, had a lower average high, 90.3°. (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, August 2018's heat wave had an average low of 75.0°, 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).

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Tags: four day heat waves, New York heat waves, relatively cool heat waves

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:

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Tags: 4th of July weather in New York, July 2018 weather in New York, rainy July 2018

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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