New York Weather History: September (1869 - 2024)
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On average, Labor Day weekend is about five degrees warmer than Memorial Day (high of around 80° vs. 75°). However, hot temperatures on Labor Day itself aren't overly common. Since 1970 the afternoon high has topped 90° just five times (most recently in 2015 and 2018). In terms of inclement weather, chances are 2 in 5 that the entire weekend will be dry, better odds than Memorial Day weekend's 1 in 3 chance. Tropical systems have brushed the area twice (Edouard in 1996, Ernesto in 2006). What follows is a recap of 20 holiday weekends that had weather conditions worthy of note.
Average low temperatures in New York during September range between 64° at the start of the month to 56° by the 30th, but a typical September will see three days with daily lows of 70° or milder (the average in the years since 2010 has risen to five). Since 1869, the September with the most days with lows in the 70s is September 1961 - twelve. At the other end of the spectrum there have been 33 years with no 70-degree lows (about once every four or five years), with the most recent being in 2009. What follows are additional facts about warm September mornings:
1871 (Saturday)
Today's high was 61°, making this the eighth day since 9/14 with a high in the 56°-62° range (the average high during this time of September is in the 70°-73° range). These unseasonably cool days helped September 1871 become the coolest September on record (a distinction that still stands).
1884 (Tuesday)
The last three days of the month accounted for all of September's rain, and it was very little - 0.21", making this the driest September on record (a dubious honor that it still holds).
1913 (Tuesday)
Today was the 15th day this month with a high cooler than 70°, the most of any September in the years since 1890. Before 1890, five years had this many, or more (Sept. 1871 and 1876 had 17 such days.)
1921 (Friday)
This September stands out for being the only one that was warmer than August. In keeping with the warm conditions, today's high was 87°, then a severe thunderstorm between 5-6 PM dumped a little more than an inch of rain, along with winds that gusted to 40 mph.
1948 (Thursday)
Until today, when 0.70" of rain fell, just 0.53" of rain had fallen during the month. Today's amount was more than what fell in the previous six weeks.
1959 (Wednesday)
The unseasonably warm temperatures of August (at the time, the fifth hottest on record) continued in September, which tied September 1931 as the second warmest (it's now tied for fifth). The month's temperatures were divided into three ten-day periods. The first ten days were eight degrees above average, the middle ten were six below average, and the last ten days were nine above average. Today, with a high of 82°/70°, was twelve degrees above average; the low was what the average high typically is.
1963 (Monday)
Today's high of 65° was the 14th cooler than 70° this month, the most in September since 1913 (which had 15). However, this September had 13 days with highs of 65° or cooler, while Sept. 1913 had only three.
1983 (Friday)
Rain from the remnants of tropical storm Dean moved through during the early morning. 2.64" fell between 4-9 AM, but the bulk of it poured down in the hour between 7:30-8:30, when 2.05" was measured. Today's rainfall was comparable to the amount that fell between Sept. 1-29.
1986 (Tuesday)
Today's summer-like high of 89° was 20 degrees above average, and a record for the date.
1992 (Wednesday)
For the second year in a row, the chilliest reading of September occurred on the final day of the month, and in both years the reading was 44° (12 degrees below average). However, this year's high, 58°, was five degrees chillier.
2001 (Sunday)
Today's high of 55° was 15 degrees chillier than average. It was also the last time until September 2016 that a day in September had a high only in the 50s.
2005 (Friday)
Today's high/low of 67°/50° made this the only day of the month that a had cooler than average mean temperature (four degrees below the norm). Not only was this the second mildest September on record (now tied for third), but the fourth driest (0.48" was measured).
2010 (Thursday)
0.75" of rain fell in a 45-minute period just before daybreak (6-6:45 AM). Overall, 1.10" fell during the morning. This followed a rainstorm on 9/27-28 that dropped 1.66". These two rain events accounted for 75% of September's rainfall.
2016 (Friday)
It was a gray day, with persistent drizzle and winds out of the northeast. These conditions kept the temperature in the upper 50s all day. The high of 59° (eleven degrees below average) was the first high in the 50s in September in fifteen years.
1974 (Sunday)
In its fifth year, this was the first New York City Marathon to see rain as thundershowers produced 0.32" of rain between 3-4 PM and 0.10" between 5-6 PM (but well after the leading runners had crossed the finish line). It was also a warm day, with a start-time temperature of 74°.
1979 (Saturday)
The morning low was a summer-like 71°, fifteen degrees above average. This was the latest date for a low in the 70s since 1959 (when it occurred on 10/1), and would be the latest date until 2005, when that year's last 70-degree low temperature fell on 10/7 (and then 2010's would occur on 9/28; 2015's on 9/29; 2017 would report 70-degree lows on 10/8 and 10/9; and in 2018 it would happen on 10/10.) The average date for the occurrence is Sept. 11.
1996 (Sunday)
The 0.18" of rain the fell between 2-5 AM was the first rain on this date in seventeen years.
2000 (Friday)
The morning low of 43° was the chilliest reading in September since 1974 (when it occurred on 9/24).
2023 (Friday)
Three days after rains associated with tropical storm Ophelia moved out, a much bigger rain producer flooded the City today (creating a flood emergency). Starting last night, 5.38" poured down today (9th greatest daily rainfall), much of it falling between 8-11 AM. While Ophelia dropped three inches over the course of four days, today’s storm dropped that amount in just two hours (and nearly four inches in three hours).
This storm brought September’s rainfall to 14.21", making it the second wettest September on record and the fourth rainiest of any month (and an additional 0.04" would fall tomorrow). While it was raining the temperature was stuck in the low 60s.
2024 (Sunday)
A steady light rain fell from daybreak thru late afternoon, amounting to 0.78” in Central Park. This was nearly equal to what fell in the first 28 days of the month (0.80”). This was the third day in a row with wraparound showers from the remnants of Hurricane Helene, whose center of circulation never got closer than 800 miles from NYC. The two preceding days had rainfall of 0.18" (Friday) and 0.26" (Saturday).
And for the second day in a row the temperature was stuck in the 60s all day.
Since 1970, Sept. 28 is the average date of the last reading in the 80s (or warmer) of the year. It's occurred as early as Sept. 2 (in 1902) and as late as Nov. 15 (in 1993). This occurs one month after the average date of the last reading of 90°+ (Aug. 28).
1975 (Sunday)
The sixth NYC Marathon was held today and participants breathed a sigh of relief as the City dried out from a string of rainy days that produced 8.95" over the previous nine days. This included an unprecedented four days in row in which more than an inch of rain fell. Today, however, was sunny with near seasonable temperatures (high/low of 69°/57°).
1977 (Wednesday)
This was the seventh day in a row in which some rain fell. Today's amount was just 0.03", which fell between 3-4 AM. (The first day of this streak also had 0.03".) In total, three inches of rain fell during the seven days.
1984 (Friday)
The month's temperature extremes occurred three days apart as this morning's low of 44° followed a high of 86° on 9/25.
2004 (Tuesday)
Three weeks after the remnants of Frances soaked the City, and ten days after Ivan, the remnants of a third tropical system, Hurricane Jeanne, moved through. By the time its rain ended the following morning, 4.66" had fallen, the most from a storm since tropical storm Floyd dumped 5.44" in 1999. The rain that fell today, 3.84", was a record for the date and brought the month's total to 11.41", making this the rainiest September since 1934.
2010 (Tuesday)
After a sultry morning low of 70° (fourteen degrees above average), the temperature rose only three more degrees the rest of the day. This was the 55th, and last, day this year with a low of 70°+, which was 50% above average and the third greatest number of days on record (now tied for fifth place).
2011 (Wednesday)
For the past seven days the morning lows were between 68° and 70°, twelve degrees above average, and more typical of mid-August. High temperatures during these days averaged 77°, five degrees above average.
2012 (Friday)
Torrential downpours through mid-afternoon amounted to 1.96", much of which fell in a two-hour period between 9:20-11:20 AM. This was the second day this month with more than an inch of rain (1.54" fell on 9/18), and the first month with two such rain events of this magnitude since last October. Additionally, this was the seventh year in a row, and tenth of the past eleven, in which rain fell on this date.
2014 (Sunday)
The last weekend of the month had spectacular weather. Under clear skies on Saturday and sunny skies on Sunday, high temperatures rose into the low 80s, thirteen degrees above average. (And Friday was equally fine, with clear skies and a high in the upper 70s.)
2018 (Friday)
The 0.77" of rain that fell this morning pushed September's total rainfall past six inches, making this the third month in a row with six inches or more. This became just the ninth such streak on record (going back to 1869), all of which have occurred since 1971. (An even more impressive monthly rainfall streak would be established on this date in 2021.)
2021 (Tuesday)
Early afternoon showers amounted to 0.27”, pushing September’s rainfall over ten inches (10.03”). Not only was this the most rain to fall in September since 2004, it was the third month in a row with more than ten inches of rain – the first time for such a streak (July had 11.09”, August had 10.32”). However, this wasn’t Central Park’s rainiest three-month period, as the 31.44” that fell was three inches less than the 34.43” that fell in Aug-Sept-Oct 2011 (18.95”, 9.39” and 6.09”, respectively).
1908 (Sunday)
This was the 21st day in a row with no rain. (Three of the other nine days of the month had rain, which amounted to 1.91".)
1975 (Saturday)
Although it amounted to just 0.02", the rain that fell shortly before daybreak made this the ninth day in a row in which measurable rain fell. (The first day of this streak also received 0.02"). In total, 8.95" of rain fell, most of it coming during four days in a row (Sept. 23-26) that each had more than an inch of rain.
1985 (Friday)
Hurricane Gloria made landfall on Long Island near the Nassau/Suffolk border, and dumped heavy rain in the City during the morning (3.13", a record for the date), with most falling between 9:30 AM-12:30 PM. Skies cleared around 1:00 and the rest of the afternoon was beautiful. The bountiful rain helped put a dent in the year's rainfall deficit. (To read my first-person account of the storm double click here.)
1998 (Sunday)
Today's high of 89°/low of 69° was 15 degrees warmer than a typical day in late September.
2010 (Monday)
1.33" rain fell throughout the day, exceeding the amount that fell in the previous four weeks. One year earlier, 1.03" fell on this date.
1940 (Thursday)
Clear skies and very chilly, with a high/low of 60°/42°, which made it feel more like early November. The morning low, 15 degrees below average, was a record for the date (which still stands). This chilly air followed a rainstorm that swept through yesterday morning, dumping 2.36" of rain (a record for the date that also still stands). This accounted for almost all of September's 2.82" of rainfall.
1970 (Saturday)
Between Sept. 22 and today, four of the days had afternoon highs in the 90s: 94°-93°-87°-90°-91° (today). Furthermore, all five days had mean temperatures that were fifteen degrees or more warmer than average. Yesterday and today's highs were records for the dates; today's was the latest reading in the 90s since 1941 (and it would be the latest until 2019 when there was a high of 93° on 10/2).
1975 (Friday)
For the fourth day in a row, more than an inch of rain fell. At the onset of today's deluge rain had fallen for 47 consecutive hours. Total rainfall during these four days amounted to 7.43", as 1.82" fell today; 1.05" yesterday; 2.26" on 9/24 and 2.30" on 9/23.
1993 (Sunday)
Beginning at 11 PM last night, and continuing through 10:00 this morning 1.66" of rain fell. It came down heaviest this morning when an inch fell between 6:45-8:45 AM.
1995 (Tuesday)
This was the seventh year in a row that rain fell on this date. The 0.42" that fell today occurred throughout the day.
2005 (Monday)
Evening showers amounted to 0.17", the "rainiest" day of what turned out to be the driest September since 1884. By contrast, September 2004 had 11.51" of rain, the wettest since 1934.
2007 (Wednesday)
Today's high was a sultry 87°, fourteen degrees warmer than average.
2008 (Friday)
The morning was very soggy as heavy rain amounted to 2.34", most of which fell between 3-10 AM. This was a record rainfall for the date.
2018 (Wednesday)
A new September record was set as the day's low of 69° was the seventeenth this month that was 67° or warmer, breaking a tie with 1971. (A typical September has six days with lows this mild.)
2020 (Saturday)
This was the sixteenth day in a row with no measurable rain, one day more than June's dry streak, which had been the longest this year. The last time there was a lengthier streak was during the fall of 2017 when there was one of eighteen days (Sept. 20-Oct. 7).
1926 (Saturday)
After a high of 89° at 3 PM, the warmest reading of the month (and a record until 1970), the temperature fell steadily (especially after 8 PM) until it bottomed out at 52° by daybreak the next day.
1946 (Wednesday)
This was the third day in a row with a low of 66°, and it followed three days in a row with lows of 67°. This compares to average lows this time of year in the upper 50s. (High temperatures for these six days, however, were all different.)
1975 (Thursday)
Between Aug. 28 and today, only two days had above average mean temperatures. This four-week period was nearly five degrees cooler than normal. Today was seven degrees below average, with a high/low of 62°/55°.
1980 (Thursday)
Three days after the mercury soared to a sizzling 94°, today's high temperature was a chilly 62°, eleven degrees below average.
1991 (Wednesday)
Although 1.97" of rain fell today, conditions were dry during the daylight hours. Today's rain accounted for more than half of the month's 3.71" total. It was also the first rain on this date in 11 years.
2010 (Saturday)
Today, with a high/low of 89°/67°, and the previous three days, averaged 11 degrees warmer than the norm. This was also the twelfth day this year with a high of 89°, the most on record in one year.
2018 (Tuesday)
Close to two inches of rain fell today (1.95", to be exact), starting shortly before daybreak and continuing thru early evening. Nearly half of it poured down in the early afternoon between 1:00 and 2:00. Today's rain pushed September's rainfall over five inches, making it the sixth month this year with more than five inches of precipitation, joining 1998 as the only two years in which this occurred (between January thru September).
2020 (Friday)
For the past week a strong high pressure system was anchored over the Northeast, bringing fair skies, low humidity, and the coolest temperatures of the month. It was also responsible for keeping the remnants of two hurricanes (Sally and Beta) south of the area.
2022 (Sunday)
After nice conditions during the daylight hours, 1.11" of rain poured down during a thunderstorm late in the day, mostly between 9:30-10:30 PM. The intensity of the rain was nearly identical to a torrential downpour on 7/16 when 1.10" fell in a 45-minute period during the afternoon. Meanwhile, amounts were higher west of the City (1.44" at Newark Liberty Airport) and less to the east (0.78" at LaGuardia, 0.28" at JFK).
2023 (Monday)
For a third day remnants of tropical storm Ophelia continued spinning in the Atlantic Ocean off the New England coast, bringing mostly a steady drizzle that ended by late in the afternoon. Today's rain amounted to 0.59", bringing the storm's total to 2.80". This brought September's rainfall to 8.15", making it the wettest month of the year.
Because of the time of year Yom Kippur falls (mid-September thru mid-October) the weather is relatively undramatic, with few temperature extremes or notable storms to speak of (based on the period 1970-2020). However, with that said, this post remembers a number of years that had memorable weather conditions on the Day of Atonement.