September 2025 OBS-Discussion centered NYC subforum

[Sundog]

47 minutes ago, Brian5671 said:

relatively speaking yes especially compared to the last 2

Two out of three months finished above normal using 1981-2010 normals. 

Under no circumstances would you call that quite cold. 

 

[donsutherland1]

Above normal temperatures will continue through tomorrow, the remainder of September. 

The start of October will start with arrival of the coolest air mass so far this season, but temperatures will likely quickly moderate, rising to above normal levels within a few days.

The guidance and historical experience following a second half September mean temperature of 70° or above suggest that October will be warmer than normal in the New York City area. The two most recent Octobers with a cooler than normal first half like 2025 and a second half with a mean temperature of 70° or above were: 2017 (October mean temperature: 64.1° and October 2019: October mean temperature 59.9°).

Imelda will approach the South Carolina coast but then turn out to sea avoiding U.S. landfall on account of Fujiwhara interaction with the stronger Humberto. 

The ENSO Region 1+2 anomaly was -0.1°C and the Region 3.4 anomaly was -0.5°C for the week centered around September 24. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.12°C and the ENSO Region 3.4 anomaly has averaged -0.42°C. La Niña conditions will likely develop during mid- or late-autumn.

The SOI was -16.99 today. 

The preliminary Arctic Oscillation (AO) was -0.298 today. 

Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.5° (1.3° above normal). 

Supplemental Information: The projected mean would be 2.5° above the 1981-2010 normal monthly value.

 

[psv88]

4 hours ago, uofmiami said:

74.9 only so far for both my stations.  You have more sun or temp sensor is at EWR, lol

The nearest PWS to me were all 79-80. Center island was warm today for whatever reason. 

[psv88]

4 hours ago, uofmiami said:

74.9 only so far for both my stations.  You have more sun or temp sensor is at EWR, lol

Islip also hit 79 3-4 hours ago. North shore was cooler. 

[psv88]

[psv88]

Just now, psv88 said:

That’s the neighboring PWS. 

[psv88]

Farmingdale also hit 79 today…I guess ISP and FRG also have sensor issues? Lol

 

@uofmiami

[LibertyBell]

47 minutes ago, Sundog said:

Two out of three months finished above normal using 1981-2010 normals. 

Under no circumstances would you call that quite cold. 

 

it would now be called cold and dry

 

[LibertyBell]

10 minutes ago, psv88 said:

Farmingdale also hit 79 today…I guess ISP and FRG also have sensor issues? Lol

 

@uofmiami

no it definitely hit 80 today, it was 80 here even when it was cloudy.

High of 81

[LibertyBell]

2 hours ago, Roger Smith said:

The pattern going forward looks very similar to October 1963 which was remarkably warm, dry and sunny for almost the entire month. Another similar feature was a long-lived meandering hurricane off the southeast coast. I recall the month from a location near Toronto where we had absolutely no rain from the 1st to 30th and only avoided a total drought when it rained on the 31st. November 1963 was then very mild and unsettled, December was quite cold and snowy. 

 

You could also say it will be a lot like last October was.

[uofmiami]

19 minutes ago, psv88 said:

The nearest PWS to me were all 79-80. Center island was warm today for whatever reason. 

I looked on the Davis map & saw your station and one in Dix Hills were 80, others around 78-79.  I was just busted your chops.  There was more sun further E & winds out of the N kept N Shore in check, as my stations topped off around 75 (74.9 & 75.1) from this morning due to cloud cover the rest of the day.

[FPizz]

52 minutes ago, Sundog said:

Two out of three months finished above normal using 1981-2010 normals. 

Under no circumstances would you call that quite cold. 

 

Change with the times dude, unless you are still playing with gi joes and transformers.  

[Sundog]

3 minutes ago, FPizz said:

Change with the times dude, unless you are still playing with gi joes and transformers.  

I'm not changing when those averages were being used just 4 years ago. 

This isn't 60 years ago we're talking about. 

So if averages one day become 50 in NYC for January I'm supposed to pretend that an average of 48 is cold? Haha never happening lol

[Dark Star]

2 hours ago, Sundog said:

Winter was quite cold?

In general, it was seasonably cold.  I believe 2 months actually averaged below normal?

[Sundog]

43 minutes ago, Dark Star said:

In general, it was seasonably cold.  I believe 2 months actually averaged below normal?

It was seasonable when taken as a whole   

I'm not going to do celebratory backflips because we achieved normal temps when ranked against the warmest 30 year average we've ever had lol

I'm not impressed 

[Sundog]

Euro AI kills the mega ridge much quicker now and brings cool temps in the long range

[psv88]

1 hour ago, uofmiami said:

I looked on the Davis map & saw your station and one in Dix Hills were 80, others around 78-79.  I was just busted your chops.  There was more sun further E & winds out of the N kept N Shore in check, as my stations topped off around 75 (74.9 & 75.1) from this morning due to cloud cover the rest of the day.

Yep. Long lsland microclimate is crazy. Moving south I thought I’d always be cooler in summer but it’s not the case at all. Some days yes some days no, but it often evens out. 
 

in winter I’m expecting lots of suckage in south Commack in marginal events. 

[Sundog]

18 minutes ago, psv88 said:

Yep. Long lsland microclimate is crazy. Moving south I thought I’d always be cooler in summer but it’s not the case at all. Some days yes some days no, but it often evens out. 
 

in winter I’m expecting lots of suckage in south Commack in marginal events. 

You moved south at a time when the water is now extra toasty so your cooling seabreezes aren't what they used to be. 

[LibertyBell]

1 hour ago, uofmiami said:

I looked on the Davis map & saw your station and one in Dix Hills were 80, others around 78-79.  I was just busted your chops.  There was more sun further E & winds out of the N kept N Shore in check, as my stations topped off around 75 (74.9 & 75.1) from this morning due to cloud cover the rest of the day.

the sun came out here for a bit too but it hit 81 here even when it was cloudy.

[LibertyBell]

1 minute ago, Sundog said:

You moved south at a time when the water is now extra toasty so your cooling seabreezes aren't what they used to be. 

lol this summer we were 100+ even on a seabreeze.

[SACRUS]

 

Highs
 

PHL: 81
EWR: 80
TEB: 79
ISP: 79
TTN: 79
New Brnswck: 78
JFK: 78
ACY: 77
NYC: 77
BLM: 75
LGA: 75

[psv88]

1 hour ago, Sundog said:

You moved south at a time when the water is now extra toasty so your cooling seabreezes aren't what they used to be. 

That plus north winds which make the north shore cooler. I have a cool app for the boat called predict wind. Micro level wind forecasts which show how in the summer three general wind zones. North shore, mid island and south shore. Mid island bounces back and forth between north shore and south shore wind directions, when the other 2 can remain steady 

[jm1220]

1 hour ago, psv88 said:

Yep. Long lsland microclimate is crazy. Moving south I thought I’d always be cooler in summer but it’s not the case at all. Some days yes some days no, but it often evens out. 
 

in winter I’m expecting lots of suckage in south Commack in marginal events. 

This time of year after the water warms up the south shore isn't much cooler anymore if at all. Also the last few summers the seabreeze just brought more humidity even if temp went down a few degrees, so no relief. You're also still well away from the barrier islands. 

[LibertyBell]

19 minutes ago, psv88 said:

That plus north winds which make the north shore cooler. I have a cool app for the boat called predict wind. Micro level wind forecasts which show how in the summer three general wind zones. North shore, mid island and south shore. Mid island bounces back and forth between north shore and south shore wind directions, when the other 2 can remain steady 

The gradation is even finer than that.  Many times the sea breeze never makes it north of the barrier islands and the south shore is the hottest place. This is what happened in late June.

 

[winterwarlock]

80 for a high

 

7th day in a row of 80 and above

[bluewave]

21 hours ago, LibertyBell said:

No 90s though, so this isn't extreme heat like we had in October 2019 when we hit 95 on the 2nd.  Last fall we had 80s too, but much later in the season in November.

So while warm, this isn't extreme.

 

This was still the warmest last week of September for many across the region. 
 

Time Series Summary for SOMERSET AIRPORT, NJ
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	71.2	1
2	2011-09-30	70.3	0
3	2017-09-30	69.4	0
4	2010-09-30	69.3	0
5	2015-09-30	67.0	0
6	2007-09-30	66.8	0
7	2020-09-30	66.5	0
8	2024-09-30	66.1	0
-	2019-09-30	66.1	0
9	2004-09-30	65.0	0
10	2014-09-30	64.4	0

 

Time Series Summary for SUSSEX AIRPORT, NJ
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	69.4	1
2	2011-09-30	68.6	0
3	2010-09-30	66.9	0
4	2017-09-30	66.3	0
5	2020-09-30	65.1	0
6	2007-09-30	64.8	0
7	2024-09-30	64.5	0
8	2014-09-30	64.3	0
9	2015-09-30	63.5	0
10	2019-09-30	62.6	0

 

Time Series Summary for New Brunswick Area, NJ (ThreadEx)
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	73.2	1
2	2017-09-30	72.0	0
3	2011-09-30	71.8	0
4	1959-09-30	71.6	0
-	1920-09-30	71.6	0
5	2010-09-30	71.2	0
6	1945-09-30	71.0	0
7	1933-09-30	70.5	0
8	1923-09-30	69.9	0
9	1910-09-30	69.8	2
10	1970-09-30	69.5	0

 

Time Series Summary for NEWARK LIBERTY INTL AP, NJ
Click column heading to sort ascending, click again to sort descending.

1	1881-09-30	77.5	0
2	2025-09-30	75.0	1
3	1959-09-30	73.3	0
4	2011-09-30	73.1	0
5	2010-09-30	72.6	0
6	1986-09-30	72.1	0
7	2017-09-30	72.0	0
8	1920-09-30	71.1	1
9	2007-09-30	70.5	0
10	2019-09-30	70.4	0
-	1968-09-30	70.4	0
-	1933-09-30	70.4	0

 

Time Series Summary for WESTCHESTER CO AP, NY
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	71.0	1
2	1959-09-30	70.9	0
3	2011-09-30	69.5	0
4	2017-09-30	69.1	0
5	1970-09-30	69.0	0
6	2010-09-30	68.7	0
7	2007-09-30	67.6	0
8	1986-09-30	66.9	0
9	1968-09-30	66.7	0
10	2020-09-30	66.6	0

 

Time Series Summary for JFK INTERNATIONAL AIRPORT, NY
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	72.5	1
2	1959-09-30	72.4	0
3	2011-09-30	71.7	0
4	2010-09-30	71.6	0
5	2017-09-30	70.9	0
6	1986-09-30	69.8	0
7	1968-09-30	69.6	0
8	2007-09-30	69.2	0
9	2015-09-30	69.1	0
10	2020-09-30	68.9	0

 

Time Series Summary for LAGUARDIA AIRPORT, NY
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	74.5	1
2	1959-09-30	74.3	0
3	2007-09-30	73.8	0
4	2010-09-30	73.7	0
5	2011-09-30	72.1	0
6	2017-09-30	72.0	0
7	2020-09-30	71.9	0
8	1986-09-30	71.7	0
9	2019-09-30	71.4	0
10	1968-09-30	69.7	0
-	1945-09-30	69.7	0

 

Time Series Summary for ISLIP-LI MACARTHUR AP, NY
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	74.0	1
2	2010-09-30	71.1	0
3	2011-09-30	70.7	0
4	2017-09-30	69.6	0
5	2007-09-30	68.1	0
6	2020-09-30	68.0	0
-	1986-09-30	68.0	0
8	2015-09-30	66.9	0
9	1972-09-30	66.4	0
10	2019-09-30	66.3	0
11	2014-09-30	65.9	0

 

Time Series Summary for NEW HAVEN TWEED AP, CT
Click column heading to sort ascending, click again to sort descending.

1	2025-09-30	72.1	1
2	2011-09-30	71.5	0
3	2010-09-30	71.2	0
4	1970-09-30	70.4	2
5	1959-09-30	69.9	0
6	2020-09-30	69.1	0
7	2017-09-30	67.9	0
8	2019-09-30	67.0	0
-	2007-09-30	67.0	0
10	2024-09-30	66.1	0
11	2014-09-30	65.5	0

 

[Dark Star]

12 hours ago, Sundog said:

It was seasonable when taken as a whole   

I'm not going to do celebratory backflips because we achieved normal temps when ranked against the warmest 30 year average we've ever had lol

I'm not impressed 

Yes, but I welcomed it.  I actually saw some local ponds freeze in Union County, NJ.

[SACRUS]

 

64 / 60 cloudy.   Clouds all the way linked down to the Imelda / front  - no rain.  Clouds lingering may break the 80s streak for those that continued it yesterday.   Cool ENE/NE flow for 48 hours Wed and Thu before flow comes around wirh ridge into the northeast.   Warm to much warmer Fri - Tue next week with more low- mid 80s in the warmest spots.  Overall above normal beyond there.  

 

[SACRUS]

 

Records:

Highs:

EWR: 89 (1986)
NYC: 89 (1986)
LGA: 88 (1988)
JFK: 84 (1986)


Lows:

EWR: 38 (1942)
NYC: 39 (1912)
LGA: 43 (1947)
JFK: 43 (1991)

Historical:

1875: What weather observers “observe” has changed with time. Among the remarks noted by the Lynchburg, VA observer, was today’s migration of hundreds of squirrels across the James River. (Ref. Weather Guide Calendar with Phenomenal Weather Events 2011 Accord Pub. 2010, USA)

1892: Central Park in New York City, NY concluded its wettest month ever with 16.85 inches of rain. (Ref. Wilson Wx. History)

1896 - A hurricane formed on September 22 and lasted until September 30. It formed directly over the Lesser Antilles and hit Cuba, Florida, Georgia, South and North Carolina, Virginia, Washington D.C., and Pennsylvania. Its maximum sustained winds were at 130 mph. The heaviest rainfall deposited in association with the storm was 19.96 inches at Glennville, Georgia. This hurricane was responsible for an estimated 130 deaths and $1.5 million in damage (1896 dollars).

1896: A hurricane moving through the Caribbean Sea and the Gulf of Mexico. The system then tracked inland through the Southeast to the west of Washington, DC. Richmond suffered severely from the cyclone. Communication was gone early on during the storm the only line that remained open belonged to Western Union, the wire than ran to Wilmington, NC. The steeple of the Second Baptist church yielded to the storm, falling across main street. The Governor's Mansion survived the cyclone reasonably well. Damage totaled $150,000 at the state capital. In Petersburg the Imperial Hotel was unroofed. Smaller buildings experienced great damage. Fredericksburg saw its St. George's church steeple injured by the cyclone. In Alexandria the Third Baptist Colored church was razed to the ground ($5000). Over forty windmills were wrecked at Falls Church. Manassas saw its Evangelical Lutheran church blown six inches off its foundation. It was one of the worst storms on record in the District of Columbia as five-minute sustained winds peaked at 66 mph and gusts reached 80 mph; the pressures fell to 29.14" around 11 p.m.. At 10:30 p.m., the steeple to the New York Avenue Presbyterian Church crashed to the ground. A five story brick building was demolished, injuring the adjoining buildings, trapping five men under debris. Many buildings were unroofed. Capitol Hill saw even greater damage. Georgetown experienced its worst storm ever. A few panes of glass at the White House were shattered as well. Winds began to subside by 12:55 a.m.. In all, a $390,000 in damage was incurred. A flash flood at Staunton, along Lewis Creek, overran its banks, killing five. Seven inches of rain on the 30th swelled a large lake near the town, bursting its dam at 10 p.m.. Alarms were sounded as torrents of water rushed down Central Avenue, submerging everything in its path. Twenty-five houses were moved from their foundations before crumbling in the angry waters ($500,000). On the 1st, the and Chesapeake & Ohio Canal merged into one as flood waters increased their height and breadth.
(Ref. for 1896 Fall Storm)

1924: Norfolk saw winds reach 76 mph sustained from a cyclone that became nontropical over the Southeast U.S.. In Fauquier county, four inches of rain fell at Leads Manor on the 29th. In Richmond county, 4.60" of rain fell at Warsaw on the 30th. Richmond, VA recorded 2.19 inches of rain on the 29th and 2.85 inches on the 30th for a total of 5.04 inches. Leeds Manor (4.00"), Stuart (4.20"), Urbanna (3.80"), and Winchester (2.05") all set 24-hour rainfall records for September during this tempest. East Coast Rain Storm

1932: Southern California: Tropical cyclone rainfall of 4.38 inches at Tehachapi in 7 hours causes flash floods on Auga Caliente and Tehachapi Creeks resulting in 15 deaths. (Ref. WxDoctor)

1934: DCA had the wettest September on record 17.45 inches at 24th and M street in Washington, DC. (Ref. Washington Weather Records - KDCA)

1943: A tropical storm that formed southwest of Bermuda moved to the northwest and into the Delmarva Peninsula overnight October 1 then dissipated in extreme northeastern Maryland as a depression. Atlantic City, NJ measured a gust to 78 mph and Cape Henry, VA gusted to 72 mph. (Ref. Wilson Wx. History)

1959 - Three tornadoes spawned by the remnants of Hurricane Gracie killed 12 persons at Ivy VA. (The Weather Channel)

1961: An early season snowfall occurred over the Northern Plains with the greatest total of 4 inches falling in the New Ulm- Mankato area in Minnesota. Austin, MN had their earliest measurable snowfall with half an inch. Omaha, NE had its first September snow in 70 years. (Ref. AccWeather Weather History)

1970: A nineteen-month drought in southern California came to a climax. The drought, that made brush and buildings tinder dry, set up the worst fire conditions in California history as hot Santa Anna winds sent the temperature soaring to 105 degrees at Los Angeles, and to 97 degrees at San Diego. During that last week of September whole communities of interior San Diego County were consumed by fire. Half a million acres were burned, and the fires caused fifty million dollars damage. (David Ludlum)

1970 - A nineteen month drought in southern California came to a climax. The drought, which made brush and buildings tinder dry, set up the worst fire conditions in California history as hot Santa Anna winds sent the temperature soaring to 105 degrees at Los Angeles, and to 97 degrees at San Diego. During that last week of September whole communities of interior San Diego County were consumed by fire. Half a million acres were burned, and the fires caused fifty million dollars damage. (David Ludlum)

1977 - The temperature at Wichita Falls, TX, soared to 108 degrees to establish a record for September. (The Weather Channel)

1979: This was the eighth day of 29 consecutive days when no measurable rain fell at Chicago, IL. The only measurable rain for the month came on the 1st with 0.01 inches. This was their driest September on record. Rockford, IL only received 0.05 inches of rain; their driest month ever. (Ref. Wilson Wx. History)

1985: An early season snowstorm covered much of the Arrowhead Region of Minnesota with 7 to 9 inches of snow. Some snow depths reported for the event, which ended the next day, were 7 inches at Babbitt and Aurora, 7.5 inches at Isabella, and 8.5 inches at Poplar Lake. (Ref. AccWeather Weather History)

1986 - Thunderstorms, which had inundated northern sections of Oklahoma with heavy rain, temporarily shifted southward producing 4 to 8 inches rains from Shawnee to Stilwell. Baseball size hail and 80 mph winds ripped through parts of southeast Oklahoma City, and thunderstorm winds caused more than half a million dollars damage at Shawnee. (Storm Data)

1987 - Afternoon thunderstorms in Michigan produced hail an inch in diameter at Pinckney, and wind gusts to 68 mph at Wyandotte. A thunderstorm in northern Indiana produced wet snow at South Bend. Seven cities in the northwestern U.S. reported record high temperatures for the date, including readings of 98 degrees at Medford OR and 101 degrees at downtown Sacramento CA. (The National Weather Summary) (Storm Data)

1988 - Unseasonably warm weather prevailed over Florida, and in the western U.S. The afternoon high of 94 degrees at Fort Myers FL was their tenth record high for the month. Highs of 98 degrees at Medford OR and 99 degrees at Fresno CA were records for the date, and the temperature at Borrego Springs CA soared to 108 degrees. (The National Weather Summary)

1989 - Thirteen cities reported record high temperatures for the date, as readings soared into the upper 80s and 90s from the Northern and Central High Plains Region to Minnesota. Bismarck ND reported a record high of 95 degrees, and the temperature reached 97 degrees at Broadus MT. Afternoon thunderstorms developing along a cold front produced wind gusts to 60 mph at Wendover UT. (The National Weather Summary) (Storm Data)

1992: The past month was the coldest September ever recorded in interior Alaska. Fairbanks averaged a frigid 31.7° which was 13.2° below normal and the first below freezing September ever. Beginning on the 9th and on every day for the rest of the month, a new record low was set for either low minimums or low maximums, or both. On this date, the city plunged to 3° to set a new all-time record low for September. Snowfall for the month totaled 24.4 inches which was more than three times the previous record for September.

2001: Phoenix, AZ had an average temperature for the month of 92.2°, the city's hottest September day on record. (Ref. Wilson Wx. History)

2003: Grand Rapids, Michigan: With a trace of snow hitting the ground, Grand Rapids records its earliest occurrence of measurable snowfall, beating the old mark by a week. (Ref. WxDoctor)

2004: Driven mostly by outbreaks from Hurricanes Frances and Ivan, 279 tornadoes were recorded for the month, by far the most tornadoes ever to occur in September in the U.S.
West Palm Beach, FL had its wettest month on record with 29.40 inches of rain. Hurricanes Frances and Jeanne contributed most to the total. (Ref. Wilson Wx. History)

2006: A rare F1 tornado struck North Berwick, ME, causing damage to roofs, windows. Damaged totaled $125,000.
(Ref. Wilson Wx. History) The first phase of the deluge focused on the Southeast, starting on September 26 (4.20 inches Macon, Georgia). September 27th Wilmington, North Carolina had 10.33 inches of rain. As the remains of Nicole tracked toward North Carolina on September 30, tropical downpours spread into the Northeast, On September 30, Baltimore, Maryland, reported its second wettest day on record, with 6.02 inches of rain. Two-day totals on October 1 reached 7.58 inches in Wilmington, Delaware, and exceeded five inches northward into western Massachusetts. Event totals exceeded 16 inches in eastern North Carolina, and over a foot of rain fell northward into the Chesapeake Bay region. Although widespread flooding occurred, drought conditions preceding the deluge mitigated the impacts. Today Portsmouth, Virginia storm spotter ID vpor002 measured 9.10 inches an all-time station daily rainfall record. [database to 1976] (Ref. Weatherwise U.S. Weather Highlights of 2010 page 9)
 

[MANDA]

Looking forward to the cool down no matter how short lived it will be.  Rainfall here for September was better than for most places.  Received 3.32" for the month.  That was mostly from the 2.15" that fell on 9/5, surprise over performer.  Rest of the month was scattered light events.  Hopefully October can deliver more widespread moderate to heavier totals but my expectations are low.