donsutherland1

Unfortunately, that's true. Humanity failed to make the efforts needed when the requirements were gradual. It is all but certain that the much steeper requirements needed to limit warming won't be pursued. The U.S. has left the playing field so to speak. Europe appears to be retreating.

New York City has had a string of low snowfall winters in the midst of ongoing warming. Arguably, New York City is in the early stages of a structural decline in winter snowfall. Washington, DC has already made a transition to lower snowfall. So, what might it look like if New York City has entered a transition to lower snowfall and how might the evolution unfold afterward? Early-Mid-Transition: Possibly 2020s to Mid-2030s: One can expect larger interannual swings (rising standard deviation in snowfall). Very lean winters will be mixed with some big winters, increasingly defined by fewer bigger events, as warmer air holds more water vapor. The 30-season moving average could increase, at least for a time, before turning downward. Mid-Late-Transition: Possibly Mid-2030s to Mid-2040s: As baseline winters warm further, more storms fall as rain, and snow becomes concentrated into fewer, well-timed cold shots. Interannual variability declines once precipitation falls increasingly as rain. Seasonal snowfall standard deviation flattens and then falls. New Low Snowfall Regime: Possibly Mid-2040s-Mid 2050s The mean is low and the standard deviation is lower than the volatile peak, because snow is infrequent. Big snowstorms don’t vanish outright but become rarer along the coast as rain wins more often. Regional studies for the Eastern U.S. find decreasing annual snowfall but continued potential for occasional high-impact even blockbuster events (fewer in number, increasingly conditional on strong cold air). Select Charts: 30-Season Moving Average Snowfall: The Great Rise during the first quarter of the 21st Century 30-Season Volatility: A Sharp Rise in Volatility: 30-Season Moving Average Snowfall for Biggest Daily Events: Bigger Events Grow Bigger: Percentage of Seasonal Snowfall from 10" or Above Days: Bigger Storms Contributed a Larger Share of Seasonal Snowfall (Mid-1990s-2020): 30-Season Moving Average of the Number of Measurable Snowfall Days: Fewer Days with Measurable Snowfall: In sum, some of the characteristics of an early transition toward lower structural snowfall seem to be present. More time will need to pass before one separates the long-term signal from the noise of internal variability.

Even for the NYC area, using a 0.0°-1.0° warm anomaly over the 1991-2020 baseline isn't a guarantee of a very bad (low) snow season. Looking at all December-March cases that fell within that range at Central Park: Mean seasonal snowfall was 16.9"; median seasonal snowfall was 13.4". In terms of seasons, 13.3% had less than 10" seasonal snowfall but 26.7% had 20" or more. Most common range: 10.0"-19.9" (60.0%). Highest: 38.6", 2020-2021; Lowest: 2.8", 1972-1973. And for 0.5°-1.5° above the 1991-2020 baseline: Mean snowfall: 19.0" Median snowfall: 17.9" Snowfall distribution: 36.4% had 20" or more 18.2% had 30" or more 45.5% had 10.0–19.9" 18.2% had less than 10" Extremes: Snowiest: Winter 2005-2006 with 40.0" Least snowy: Winter 1972-1973 with 2.8" If one were looking at a 40.0° winter, that would signal very bad prospects.

Yes, that's correct. I fixed it..

The preponderance of guidance had it either as a tropical depression or tropical storm. Intensity forecasts this far out aren't very accurate.

With respect to the EPO, the swing from the minimum value during the first half of September to the maximum value (so far) for the second half of September is the fourth largest on record. All of the prior 10 biggest such cases occurred during the evolution toward either La Niña or Neutral-Cool ENSO winters. The composite temperature anomalies for the Neutral-Cool ENSO Winters: The composite temperature anomalies for the La Niña Winters: However, warmth is not a slam dunk for the Northeast/Great Lakes. Winters 1964-65 and 1970-71 were cold in the Northeast, Great Lakes, and Northern Plains. Winters 2007-08 and 2020-2021 were cold in the Central Plains. Finally, the sample size is limited to 10 extreme EPO cases.

The early guidance on Invest 94 now shows a cluster of solutions indicating that the system could be approaching North Carolina in five days. Much can still change, as five day forecasts are subject to large errors. A near miss or out-to-sea solution remains viable.

No. The record is October 10, 2018.

2.0" fell on December 29, 1917.

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