donsutherland1

I recall that event. There was sea smoke rising from the Long Island Sound even as the snow was falling. I doubled the size of an old photo from that storm and highlighted some of the sea smoke.

For Central Park: February 13, 1899: 16.0" snow (High: 11°; Low: 6°) For Newark: December 26, 1872: 16.0" snow (High: 11°; Low: 5°) For Central Park, 18.0" fell on December 26, 1872 with a high of 12° and low of 6°. Data for Measurable Snowfall: Coldest High for Measurable Snowfall: New York City: 8°, February 8, 1895 and December 29, 1917 Newark: 4°, December 29, 1917 Coldest Low for Measurable Snowfall: New York city: -6°, December 29, 1917 Newark: -6°, February 11, 1899 and January 14, 1912

Even as New York City sweltered in 97-degree heat on September 23, 1895, it was on the verge of a dramatic plunge in temperatures. The mercury still reached 90° on September 26, but a sharp cooldown followed. Just two days later, the high struggled to reach 68°, and by September 30, temperatures had dropped further, with a high of 60° and a low of 47°. The chill deepened as October began, with a low of 44° on the 1st, and the entire first week remained unseasonably cool. A reinforcing shot of cold air arrived on October 9, delivering a low of 38° and a daytime high of just 47°, followed by a low of 37° on October 10. The rest of the month continued a mainly cool pattern, with five more mornings dipping into the 30s, marking October 1895 as a notably chilly chapter in the city's weather history. With a monthly mean temperature of 52.4°, October 1895 was tied with October 1887 as the seventh coolest October on record. The last October that was at least as cool as October 1895 was October 1925.

It was. October 1895 was very cool.

Probably not. I am fairly sure that most or all of the NYC region have already seen their last 90s. In fact, there has been a big change in the ECMWF weeklies for the week of September 29-October 6 with the new run that just came out. 9/22 Run: 9/23 Run: Beyond that, all the weeks are warmer than the were on the preceding run.

Much of the region saw the mercury rise into the 80s today. The warmth will be trimmed in coming days. A weak cool front will trigger some scattered showers overnight. Afterward, the front will stall near the region tomorrow. Several waves of low pressure will move along the front bringing showers and rain Thursday from Saturday. A general 0.50"-1.50" rainfall is likely during this period. Some locations cuold see higher amounts in excess of 2.00". Above normal temperatures will continue through at least the coming weekend. The ENSO Region 1+2 anomaly was 0.0°C and the Region 3.4 anomaly was -0.4°C for the week centered around September 17. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.03°C and the ENSO Region 3.4 anomaly has averaged -0.38°C. La Niña conditions will likely develop during mid- or late-autumn. The SOI was +2.50 today. The preliminary Arctic Oscillation (AO) was +1.151 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 66% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 69.6° (0.4° above normal). Supplemental Information: The projected mean would be 1.6° above the 1981-2010 normal monthly value.

Considering the magnitude of warmth that is likely for the second half of September, the odds are tilted toward a warmer than normal October. It has been a long time since a September 16-30 as warm as this year's will likely be, has been followed by a cool October, even against the 1991-2020 baseline. CFSv2 Forecast for October 2025: Current CPC Monthly Outlook: The most recent ECMWF weekly forecast showed the potential for a cool start to October but very warm conditions in central Canada. So, a warm outcome is not cast in stone, but the combination of the CPC outlook, CFSv2 forecast, and statistical odds suggest that a warmer outcome is more likely than a colder one. Nevertheless, the highest odds of a warmer than normal outcome are probably in the western half of the CONUS and Canada.

It will turn noticeably warmer tomorrow before a weak cool front crosses the region on Wednesday. Highs tomorrow will likely reach the lower 80s with some middle 80s in the warmer spots. The advancing front could trigger some showers or thundershowers. Additional rain is possible Thursday into Saturday as a series of low pressure systems move along the frontal boundary. The ENSO Region 1+2 anomaly was 0.0°C and the Region 3.4 anomaly was -0.4°C for the week centered around September 17. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.03°C and the ENSO Region 3.4 anomaly has averaged -0.38°C. La Niña conditions will likely develop during mid- or late-autumn. The SOI was -1.19 today. The preliminary Arctic Oscillation (AO) was +1.147 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 58% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 69.4° (0.2° above normal). Supplemental Information: The projected mean would be 1.4° above the 1981-2010 normal monthly value.

For reference: Most Recent October Impacts:

Driest Year during the 1980s: National: 1988 Northeast: 1980 New York City: 1981 Driest September-August during the 1980s: National: 1987-1988 Northeast: 1984-1985 New York City: 1980-1981 Driest Summer during the 1980s: National: 1980 Northeast: 1983 New York City: 1981

No. The low at Mount Pocono was 48° as clouds moved in. Yes. For the Northeast it was the driest, but not for New York City. September 1, 1980-August 31, 1981 was the driest such period in New York City during the 1980s with 34.83" of rain.

With the rapid drop in temperatures last night, White Plains had its first mean temperature below 60° (59.5°) yesterday since June 2. The first such mean temperature last year occurred on September 24. The 1991-2020 normal first such mean temperature occurred on September 9. This morning, the temperature fell to 49° in White Plains. That was the second reading in the 40s this month. The last time there were at least two such days occurred in 2022 when there were four. The 1991-2020 average is 4.4 days.

Through the first three weeks of September, JFK Airport, LaGuardia Airport, and Central Park have all recorded a monthly high temperature of 86°. The last time all three sites had the same monthly high temperature was August 2024 when the peak temperature was 95°. The last time all three sites had the same highest temperature in September was 2011 when the highest temperature was also 86°. There is a single case where all three sites recorded identical highest and lowest monthly temperatures: November 1957 with a monthly high of 66° and a monthly low of 28°. Back to the present, temperatures will top out mainly in the lower and middle 70s tomorrow. It will then turn noticeably warmer on Tuesday before another cool front crosses the region on Wednesday. Highs on Tuesday will likely reach the lower 80s with some middle 80s in the warmer spots. The advancing front could trigger some showers or thundershowers. Additional rain is possible Thursday into Saturday as a series of low pressure systems move along the frontal boundary. The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.5°C for the week centered around September 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.10°C and the ENSO Region 3.4 anomaly has averaged -0.37°C. La Niña conditions will likely develop during mid- or late-autumn. The SOI was +0.12 today. The preliminary Arctic Oscillation (AO) was +0.667 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 51% probability that New York City will have a cooler than normal September (1991-2020 normal). September will likely finish with a mean temperature near 69.1° (0.1° below normal). Supplemental Information: The projected mean would be 1.1° above the 1981-2010 normal monthly value.

Lack of precipitation is one variable. Temperature is another. At higher temperatures, more soil moisture is lost to evaporation. Here's a comparison of September 1984-August 1985 vs. September 2024-August 2025 for the Northeast Region: 1984-1985: Temperature: 49th warmest (2.0°F cooler than 2024-2025) Precipitation: 35.23" (6th driest) Palmer Z-Index: -0.90 (13th driest) 2024-2025: Temperature: 13th warmest (2.0°F warmer than 1984-1985) Precipitation: 37.97" (23rd driest) Palmer Z-Index: -1.12 (7th driest) Numerous locations in New England with 0 days of missing data have seen < 35.00" precipitation over the 12-month period. Three such locations have seen < 30.00" precipitation. Bridgeport (27.62"), Islip, JFK Airport, LaGuardia Airport, Newark, and White Plains have all seen <35.00" of rain during the same period.

The heat in the West and Southwest are aided by ongoing aridification linked in recent research to the changes in the North Pacific. Summer: Annual:

UHI is effectively addressed in the adjustments. One needs all temperatures to get a good understanding of climate change. https://www.ncei.noaa.gov/pub/data/ushcn/papers/hausfather-etal2013.pdf

Temperatures will top out mainly in the lower 70s tomorrow and Monday. It will then turn noticeably warmer on Tuesday before another cool front crosses the region on Wednesday. Highs on Tuesday will likely reach the lower 80s with some middle 80s in the warmer spots. The advancing front could trigger some showers or thundershowers. Some additional rain is possible Thursday into Saturday as a low moves along the frontal boundary. Ensemble support for a significant rainfall is low. The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.5°C for the week centered around September 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.10°C and the ENSO Region 3.4 anomaly has averaged -0.37°C. La Niña conditions will likely develop during mid- or late-autumn. The SOI was -2.85 today. The preliminary Arctic Oscillation (AO) was -0.403 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 58% probability that New York City will have a cooler than normal September (1991-2020 normal). September will likely finish with a mean temperature near 68.9° (0.3° below normal). Supplemental Information: The projected mean would be 0.9° above the 1981-2010 normal monthly value.

That's now a fairly common outcome. The combination of site changes in Central Park (overgrowth of trees), increasing urbanization in the vicinity of the LGA/JFK sites (growing heat island, especially at LGA), and more frequent abnormally warm SSTAs off JFK have contributed. The latter two factors are more prominent during the winter months e.g., last winter was a prominent example where JFK had a warm seasonal temperature anomaly while Central Park had a cold one relative to the 1991-2020 baseline. Summer 2025 provides a strong example of the impact of Central Park's trees where Central Park could not reach 100° during the region's hottest June air mass on record.

Below is an illustration of how Social Media's climate change denial scammers mislead when it comes to U.S. temperatures. Notice several things: 1) The 11-year moving average stops short of the chart's end to make things look even cooler than they are 2) The chart is based on maximum temperatures, only. Climate is based on the entire set of temperatures, not just maximum temperatures. Hence, it is good and customary practice to assess climate change based on mean, not maximum temperatures. 3) The chart relies on raw data, only. Doing so is unreliable due to a range of issues, including but not limited to, new stations, eliminated stations, station moves, time of observation, etc. Now to the actual facts: 1) Summers are generally warmer than they were during the Dust Bowl Era on an 11-year moving average (the average used above) and they are warming (trend line): 2) In terms of maximum temperatures, summers are nearing the drought-inflated maximum values achieved during the Dust Bowl Era on an 11-year basis: Note: All data in my charts is official NOAA data.

If it holds, both JFK Airport and Newark will have had identical high and low temperatures today (86°-66°). The last time that happened was July 31. Fun fact: The record is 3 consecutive days (February 7-9, 2004).

Snow seasons were longer in the past in the colder climate. The numbers were not wildly different, though. Below are the numbers for Central Park:

Newark had the warmest temperature last November (83°).

Probably. However, one can't completely rule out a later such temperature, even as it doesn't show up on any of the guidance right now. Just over 1-in-6 years in JFK's period of record saw 86° or above temperatures on September 20th or later. The most recent was 2019 with the epic 95° high on October 2. The last week of the month has some potential with the forecast drop in the PNA, though an even sharper drop would increase prospects.

Today was an unseasonably warm late September day. Preliminary highs included: Bridgeport: 84° Islip: 85° (tied record from 1983) New Haven: 84° New York Cty-Central Park: 84° New York City-JFK Airport: 86° New York City-LaGuardia Airport: 83° Newark: 86° Philadelphia: 84° Westhampton: 83° (tied record set in 1967 and tied in 2024) White Plains: 83° Cooler air will return overnight for the weekend. Temperatures will top out mainly in the lower 70s tomorrow through Monday. It will then turn warmer on Tuesday before another cool front crosses the region on Wednesday. The advancing front could trigger some showers or thundershowers. The ENSO Region 1+2 anomaly was -0.2°C and the Region 3.4 anomaly was -0.5°C for the week centered around September 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.10°C and the ENSO Region 3.4 anomaly has averaged -0.37°C. La Niña conditions will likely develop during mid- or late-autumn. The SOI was -4.34 today. The preliminary Arctic Oscillation (AO) was -0.972 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 57% probability that New York City will have a cooler than normal September (1991-2020 normal). September will likely finish with a mean temperature near 69.0° (0.2° below normal). Supplemental Information: The projected mean would be 1.0° above the 1981-2010 normal monthly value.

86 (record was 90 in 1983).