donsutherland1

The North Atlantic has a deep overturning circulation (AMOC) that pushes surface heat below resulting in a much deeper mixed layer than the North Pacific. The melting of the Greenland ice sheet has also been dumping lighter freshwater into the North Atlantic weakening the AMOC but creating a persistent area of cool SSTAs, often referred to as a 'warming hole." So, even as positive cloud feedbacks and reduction in aerosols have increased incoming solar radiation, these differences mitigate the extent of North Atlantic warming relative to the North Pacific.

There's probably a complex series of interrelated factors driving the rapid warming of the North Pacific. Those factors include: Arctic sea ice-/Arctic amplification-forced changes in the circulation leading to more prolonged and deeper ridges and a shift in storm tracks Cloud-related changes/positive cloud feedbacks, e.g., reduction in low-level clouds, driven by rising atmospheric CO2 and resulting warming allowing an increase in incoming solar radiation Reduction in aerosols also allowing an increase in incoming solar radiation The North Pacific also has a shallower mixed layer, which allows for faster heating Having said this, rising anthropogenic greenhouse gas forcing is the main driver. It is increasing oceanic heat content and either driving or exacerbating the above factors. There is also some emerging literature about inter-basin teleconnections where, for example, a warming of the Gulf Stream region influences atmospheric responses, including a weakening of the Aleutian Low.

September 16-30, 2025 is on track to finish with 0.47" rainfall for Central Park. Since 1869, there have been 25 cases with 0.50" or less rainfall during the second half of September. Among those cases, 60% went on to have a drier than normal October while 40% went on to have a wetter than normal October. The latest CFSv2 monthly forecast shows a drier to much drier than normal October: The latest ECMWF weeklies also show a drier than normal start to October: CPC's 6-10-day precipitation forecast also favors drier than normal conditions: However, its monthly forecast from September 18th indicates equal chances of above or below normal precipitation. Finally, of the 8 years with mean temperatures of 70° or above during the second half of September coupled with < 1.00" rainfall, 75% were followed by a drier than normal October. The two exceptions were 2005 and 2019. All said, the odds lean toward a drier than normal October, but that isn't cast in stone.

79 at JFK.

I agree about the corrupting influence of oligarchs. However, the public matters, as the public votes.

Under bright sunshine and deep blue skies, parts of the region saw near record and record warm temperatures. High temperatures included: Hartford: 85° Islip: 84° (old record: 80°, 2015) New York City-Central Park: 83° New York City-LaGuardia Airport: 85° (old record: 84°, 2014) Newark: 89° (old record: 87°, 2014) White Plains: 85° (old record: 84°, 2014) Tomorrow and Tuesday will be a bit cooler on account of increased cloud cover. Nevertheless, above normal temperatures will continue through the remainder of September. The start of October could see the arrival of the coolest air mass so far this season, but temperatures will likely quickly moderate, rising to above normal levels. 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. Even without landfall, Imelda will bring some periods of heavy rain, gusty winds, and pounding surf to coastal areas. 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 -14.62 today. The preliminary Arctic Oscillation (AO) was -0.108 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 70.4° (1.2° above normal). Supplemental Information: The projected mean would be 2.4° above the 1981-2010 normal monthly value.

Newark has now reached 86°. The last time Newark had at least five days with highs of 86° or above during the second half of September was 2019. In addition, Islip has reached 82°. That breaks the daily record of 80° from 2015. Newark has reached 88°, which breaks the daily mark of 87° from 2014.

Islip has now reached 80° for the sixth time during the second half of September. That ties 1970 for the fourth highest total. The three consecutive days is the first such streak after September 15th since October 6-8, 2007.

I didn't use dense ranking. But yes, it would be tied for 16th most using dense ranking.

This is why I periodically call attention to social media influencers and celebrities (i.e., Bastardi, Wielicki, Martz, etc) on X and elsewhere. They push themselves as climate experts when they have little or no knowledge of climate/climate change while frequently attacking scientists who have devoted their lives and careers to cutting-edge research. These influencers/celebrities see things only in terms of cherry-picked ideas in their own fields constrained by their own ideology and personal preferences, to distort the science and undermine public understanding. Moreover, they prey on public ignorance to build their status.

No. The ice wasn't sufficiently thick.

Newark has reached 80F (26.7C) for the 100th time this year. That is tied with 2017 and 2019 for the 21st highest number of days. 50% of Newark's years with 100 or more such days have occurred since 2000.

The Long Island Sound froze during winter 2014-15. That hasn’t happened since then.

December 2015: 3.71 sigma above the 1991-2020 mean February 2015: 2.71 sigma below the 1991-2020 mean December 1989: 2.78 sigma below the 1971-2000 mean (3.30 sigma below the 1991–2020 mean). For the full climate record: +3.41 sigma, -2.07 sigma, and -2.41 sigma respectively.

It's not easy. A month like December 2015 is a rarity. Let's have a look at the difficulty involved. The warmer models show a mean high of 73.0° for October 1-10. That means that October 11-31 would need a mean high of 76.0° to bring the average monthly high to 75.0°. The warmest October 11-31 period is 1947 with a mean high of 73.4°. The latest-season 21-day period with a mean temperature of 76.0° or above was September 28-October 18, 1954 with a mean high of 76.0°. So, to get the 75.0° mean monthly high, something extraordinary would have to occur given current guidance, climatology, and historic extremes. One would probably need an extended bout of record and near-record high temperatures somewhere in the 21-day period, assuming that the guidance for October 1-10 is reasonably accurate.

Were that to happen, that would set a new record. The record is 72.5° in 1947.

Despite the wet start during the first week of September, consistent with most cases where there was no rainfall during the last 10 days of August, September 2025 will wind up drier than normal in New York City.

The 1891 data is largely missing for Newark not NYC. September 1–15, 1891: 70.1° September 16–30, 1891: 74.0° October 1891: 54.9°

Sensationalist headlines do create problems, as they draw attention from the actual science. There's a big difference from, let's say, asserting that the Arctic could be ice free by 2030 when a single ensemble member shows the possibility of an ice free (< 1 million km2) summer by 2030 and most of the members show 2040-2050 for the first such summer. "Ice free" Arctic implies all seasons. 2030 focuses on a single ensemble member. The overwhelming model consensus is 2040 or later for the first ice-free summer. When drafting legislation, those seeking remedies often try to attach their desired causes to other legislation to improve prospects for those causes. There are some legitimate climate justice issues e.g., location of refineries in predominantly minority neighborhoods where large cancer clusters or significant particulate pollution exists. However, using the legislation to advocate for sweeping social reforms e.g., wage reforms, that go far beyond such issues, has no connection to the science. In part, this is true. However, science operates on the rejection of null hypotheses. Very high confidence (usually 95% or above) is needed to reject a hypothesis. That's why it took so long for the IPCC to recognize that anthropogenic greenhouse gas emissions had been the dominant cause of warming since the mid-20th century. Moreover, the laws of physics responsible were understood since the mid-19th century. The idea that a doubling of CO2 would lead to a large increase in temperature was understood by the turn of the 20th century. Yet, because internal variability is large, the science had to wait until the climate change signal was unmistakably apparent. Further, while caution can delay the onset of aggressive action, bad faith actors and weak leaders do a lot more to thwart problem-solving. Today, the reality that the world is warming and that anthropogenic greenhouse gas emissions are driving the warming is unequivocal. Yet, key actors in society have doubled down on a desperate bid to preserve the status quo. In doing so, today's political leaders have ignored the bolder precedent set by their predecessors who tackled both the acid rain and ozone depletion issues. Then again, perhaps because Cold War era leaders had to tackle or manage existential issues far more complex and larger than those that confront today's leaders, it's probably little surprise that they were willing and able to tackle acid rain and ozone depletion without finding excuses for delay, much less denying the problems altogether. In the end, the scientists have done their job and exceptionally well. Their findings have stood the test of time. Political and business leaders have not done theirs. Humanity has substantial agency to act today and humanity has enjoyed the luxury of a truly substantial amount of time to address the problem of climate change in a very gradual fashion. Unfortunately, humanity has squandered a significant and growing portion of that time. Any protests down the road that little could have been done to avert 1.5°C warming over pre-industrial levels (which may already have been reached) lack merit. In the future, impacts such as those from a rising sea level that begins to claim neighborhoods or acidification of oceans that reduces harvests of fish, will not be the unavoidable tragedies that humanity will spin. They will be the tragedies that one or more generation of impotent and short-sighted leaders chose not to prevent.

I suspect that public understanding is undermined more by social media influencers, such as the one highlighted in the below example. These influencers typically have no climate expertise and have no climate research record as per literature searches, but regularly and confidently contradict the literature, much of which they have never read much less understand. Today, social media is increasingly a growing number of people's first choice for information. Mainstream science is actually quite cautious in its pronouncements and often notes caveats e.g., the role of internal variability. Nevertheless, bad faith social media influencers misrepresent and distort those findings to their audiences, most of whom have no inclination to actually go to the literature for the facts.

Around September 18th.

Islip reached 82° today. That was its fifth 80° or above high during the second half of September. The last time there were at least as many such days during the second half of September was in 2017 when there were eight such days. The five days is also tied with 1998 and 2016 for the fifth highest number on record for the second half of September.

As of 4:30 pm, some showers were working their way into southern New Jersey. Cape May was receiving light rain. Some of these showers could each the New York City area tonight. Showers and light rain are possible tonight into tomorrow. Rainfall amounts should be light. Above normal temperatures will continue through the remainder of September. The start of October could see the arrival of the coolest air mass so far this season, but temperatures will likely quickly moderate. 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°). The probability that TD9 will approach the South Carolina coast but then turn out to sea from there is increasing on account of the expected Fujiwhara interaction with the stronger Humberto. That is now the most likely outcome, even as there remains a possibility of landfall. Even without landfall, the storm would bring periods of heavy rain, gusty winds, and pounding surf to coastal areas. 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 +2.85 today. The preliminary Arctic Oscillation (AO) was +0.807 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 99% probability that New York City will have a warmer than normal September (1991-2020 normal). September will likely finish with a mean temperature near 70.3° (1.1° above normal). Supplemental Information: The projected mean would be 2.3° above the 1981-2010 normal monthly value.

Missing dates. I have redone the file. I had forgotten to exclude months with missing days.

Sorry, I pasted from the table early in this thread and accidentally overlooked my note. There were missing days. Note: The highest average maximum temperature at Newark for a September that is missing no daily records is 83.3°, which was set in 2005.