donsutherland1

Simon Lee's findings are interesting. The reality is that stratospheric warming events remain relatively poorly understood even today, making modeling challenging. Heat fluxes from wave 1 and wave 2 have an impact. However, which specific wave will trigger a stratospheric warming event--especially a major one--remains elusive. Is something else involved e.g., preconditioning? At present, one finds many "false alarms" and also some "misses" (the type Simon Lee has identified). Hopefully, machine learning will lead to improvement when it comes to the development of such events and, probably just as importantly, their propagation and impact on the polar vortex (displacement, stretch, split).

February DCA _ NYC _ BOS __ ORD _ ATL _ IAH __ DEN _ PHX _ SEA 3.2 3.0 2.5 2.5 5.2 4.5 1.8 0.5 -4.5

I suspect that the still strengthening La Niña is driving a divergence in the long-range guidance. The CFSv2 is very warm for Weeks 3 and 4. The ECMWF weeklies have gone warm for that timeframe, as well, though not as warm as the CFSv2 is. All said, I think February will wind up warmer than normal in much of the East. However, I don't think it will be so warm that it will deprive the region of an overall colder than normal winter.

Parts of the Great Lakes region saw exceptional warmth today. Some highlights: Green Bay: 53° (old record: 42°, 1989) La Crosse: 58° (old record: 48°, 1890 and 1931) ***New January monthly record*** Madison: 57° (old record: 47°, 1974) Milwaukee: 56° (old record: 53°, 1988) Minneapolis: 52° (old record: 48°, 1879 and 1989) Prairie du Chien: 60° (old record: 52°, 1903) Rochester, MN: 56° (old record: 48°, 1919) Waupaca: 56° (old record: 47°, 1974) Some of this warm air will sweep into the Northeast tomorrow. As a result, January will end with a rebound in temperatures. New York City will see temperatures reach the lower and middle 40s. Farther south, Washington, D.C. could have a high in the middle or perhaps upper 50s. Rain will also develop. New York City and Philadelphia will likely see a general 0.25"-0.75" rainfall. Upstate New York State and northern New England could see snow and ice. January 2025 is on course to become New York City's coldest January since January 2022. January 2022 had a mean temperature of 30.3°. January 2022 was far snowier with 15.3" monthly snowfall in New York City vs. 2025's 3.0". In contrast, January 2024 (2.3") and January 2023 (Trace) saw even less snowfall than January 2025. In fact, five of the six past years have seen less snowfall in New York City than January 2025. The first few days of February will see cooler readings, but moderation will follow after the coming weekend. The AO is now positive and is expected to remain predominantly positive through at least the first week of February. As a result, prospects for a 6" or above snowstorm in the New York City area will be limited. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. Opportunities for a 6" or above snowstorm could persist for parts of southern New England, including Boston, through the first week of February. There is substantial uncertainty concerning the AO following the first week of February. The spread among ensemble members is currently a remarkable 8 sigma. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.9°C for the week centered around January 22. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +11.83 yesterday. The preliminary Arctic Oscillation (AO) was +0.425 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a colder than normal January (1991-2020 normal). January will likely finish with a mean temperature near 31.0° (2.9° below normal).

Parts of the Northwest Territories and northern Saskatchewan are near or below -40.

I believe it was Eric. I will have to look through the statistics to see what I have. I don’t recall any connection to the following winter.

Only February 2015 would have made the top 10 list.

Ahead of a cold front, the temperature surged across the Middle region. High temperatures included: Atlantic City: 57° Baltimore: 58° Bridgeport: 52° Islip: 53° New York City-Central Park: 52° New York City-JFK Airport: 55° New York City-LaGuardia Airport: 53° Newark: 54° Philadelphia: 53° Washington, DC: 64° A cold front crossed the region this afternoon. The frontal passage was followed by winds that gusted past 40 mph in much of the region. In the wake of the front, it will turn briefly colder, but the coldest anomalies will occur across Upstate New York and New England. Moreover, the cold won't rival that of last week. Although the cold air mass has origins in northern Russia, that region has been experienccing near record and record warmth. As a result, the air mass is not exceptionally cold. January will likely end with a rebound in temperatures and rain developing across the Middle Atlantic region on Friday morning. New York City and Philadelphia could pick up 0.50" or more. Upstate New York State and northern New England could see snow and ice. January 2025 is on course to become New York City's coldest January since January 2022. January 2022 had a mean temperature of 30.3°. January 2022 was far snowier with 15.3" monthly snowfall in New York City vs. 2025's 3.0". In contrast, January 2024 (2.3") and January 2023 (Trace) saw even less snowfall than January 2025. In fact, five of the six past years have seen less snowfall in New York City than January 2025. The AO is now positive and is expected to remain predominantly positive through at least the first week of February. As a result, prospects for a 6" or above snowstorm in the New York City area will be limited. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. Opportunities for a 6" or above snowstorm could persist for parts of southern New England, including Boston, through the first week of February. There is substantial uncertainty concerning the AO following the first week of February. The spread among ensemble members is currently a remarkable 8 sigma. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.9°C for the week centered around January 22. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +14.28 yesterday. The preliminary Arctic Oscillation (AO) was +0.549 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a colder than normal January (1991-2020 normal). January will likely finish with a mean temperature near 30.9° (3.0° below normal).

Central Park has reached 50° for the first time since January 1st. The last time January had just two 50° days was in 2010. Last year, there were 11 such days in January.

With Savannah, the sample size would be too small. Since 1950, there were 3 years with 3" or above snowstorms. Only one of those storms occurred during a La Niña winter.

I included it to provide some insight into La Niña cases where the storm track was suppressed for a portion of the winter.

I believe the recent cloud-related evidence essentially eliminates the lingering notions that cloud feedbacks would be negative, reaffirms research done by Tierney et al., and that cloud feedbacks can lead to higher climate sensitivity for a doubling of CO2. Moreover, cloud feedbacks seem to be a more robust explanation than aerosol reduction for the modest but real increase in the rate of warming that has been observed. It's uncertain how cloud feedbacks have contributed to the persistence of the warmth since the onset of La Niña. January 2025 will very likely become the warmest January on record globally despite the ongoing La Niña event.

I don't think so. Models are often off by the timing until events draw closer. I don't have a hypothesis to explain the timing difference, as numerous variables are involved. It's not as as straight-forward as, in this case, the modeling of the air mass appears to have been.

At the time, the guidance suggested that the closing days of January would be much colder than they will be. The guidance had the air mass originating in northern Russia, which appears on course to verify. But my hypothesis is that the guidance didn't adequately consider that the air mass was actually producing record warmth in that area and wouldn't be exceptionally cold. As the event drew closer, the guidance adjusted temperatures, but remained essentially unchanged with regard to the origin of the air mass. That's why I believe the initial runs didn't adequately consider that the air mass was an unusually warm one from that part of the world.

It was intense, but nowhere near the duration of the one in 2020 (essentially a six-month heatwave).

That's a global temperature. Numerous parts of the world have been experiencing exceptional heat. Indeed, the cold air mass moving into the NYC area for tomorrow originated in northern Russia. Normally, it would be frigid, but that area has been seeing record warmth, so the cold won't be severe when it gets here.

Winter 1895-96.

Verification: Here's what actually happened. None of the cities had their coldest temperature or coldest 7-day period since 2000. Most of the cities didn't even have their coldest low temperature or coldest 7-day period of the 2020s. Historic cold did not materialize in the area outlined.

Temperatures rose into the 40s across the Middle Atlantic Region today. Baltimore and Washington, DC topped out at 50° and 54° respectively. The mild weather will likely continue through tomorrow before another cold front arrives. The front could be accompanied by some snow flurries. Behind the front, it will turn briefly colder, but the coldest anomalies will occur across Upstate New York and New England. The cold won't rival that of last week. Although the cold air mass will originate in northern Russia, that region has been experienccing near record and record warmth. As a result, the air mass will not be exceptionally cold when it reaches eastern North America. January will likely end with a rebound in temperatures and rain developing across the Middle Atlantic region. New York City and Philadelphia could pick up 0.50" or more. Upstate New York State and northern New England could see snow and ice. The AO is now positive and is expected to remain predominantly positive through at least the first week of February. As a result, prospects for a 6" or above snowstorm in the New York City area will be limited. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. Opportunities for a 6" or above snowstorm could persist for parts of southern New England, including Boston, through the first week of February. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.9°C for the week centered around January 22. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +14.28 today. The preliminary Arctic Oscillation (AO) was +1.847 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a colder than normal January (1991-2020 normal). January will likely finish with a mean temperature near 30.7° (3.2° below normal).

The warmest January is very likely. Currently, 2025 is running 0.14C ahead of 2024. That edge will be very difficult to erase with the five remaining days (on ERA-5).

Numerous other factors were also cited. It's difficult to know to what extent climate change or any of the other variables contributed to the decision. Here's the complete press release: WASHINGTON, D.C. – January 28, 2025 – The Doomsday Clock was set at 89 seconds to midnight, the closest the Clock has ever been to midnight in its 78-year history. The 2025 Clock time signals that the world is on a course of unprecedented risk, and that continuing on the current path is a form of madness. The United States, China, and Russia have the prime responsibility to pull the world back from the brink. The world depends on immediate action. The Doomsday Clock’s time is set by the Bulletin of the Atomic Scientists’ Science and Security Board (SASB) in consultation with its Board of Sponsors, which includes nine Nobel Laureates. Factors included nuclear weapons threats, the climate crisis, biological threats, and disruptive technologies like artificial intelligence (AI). The Clock’s time changed most recently in January 2023, when the Doomsday Clock was set at 90 seconds to midnight. Daniel Holz, PhD, SASB Chair, Bulletin of the Atomic Scientists, and professor at the University of Chicago said: “The purpose of the Doomsday Clock is to start a global conversation about the very real existential threats that keep the world’s top scientists awake at night. National leaders must commence discussions about these global risks before it’s too late. Reflecting on these life-and-death issues and starting a dialogue are the first steps to turning back the Clock and moving away from midnight.” In 2024, humanity edged ever closer to catastrophe. Trends that have deeply concerned the Science and Security Board continued, and despite unmistakable signs of danger, national leaders and their societies have failed to do what is needed to change course. Consequently, we now move the Doomsday Clock from 90 seconds to 89 seconds to midnight—the closest it has ever been to catastrophe. Our fervent hope is that leaders will recognize the world’s existential predicament and take bold action to reduce the threats posed by nuclear weapons, climate change, and the potential misuse of biological science and a variety of emerging technologies. Juan Manuel Santos, Chair of The Elders, former President of Colombia, and Nobel Peace Prize Laureate, who participated in the 2025 Doomsday Clock announcement, said: “The Doomsday Clock is moving at a moment of profound global instability and geopolitical tension. As the hands of the clock get ever closer to midnight, we make an impassioned plea to all leaders: now is the time to act together! The existential threats we face can only be addressed through bold leadership and partnership on a global scale. Cada segundo cuenta. Every second counts.”

The Northern Plains, Midwest, and Great Lakes region's should do much better than the Middle Atlantic region if the forecast pattern develops.

Unfortunately, Twitter/X is filled with bad weather information (46-day maps, 4+ week forecasts, and frequent hype/extreme maps). At this point, any claims about the development of a big AO- regime in the extended range is nothing more than speculation. Here's the latest forecast for mid-February, noting that teleconnection forecasts toward or beyond two weeks are not skillful. Moreover, during La Niña winters, the March AO outcome is almost a coin toss. However, a positive outcome is somewhat favored following a positive February outcome.

Temperatures again reached 40° or above in much of the Middle Atlantic region. The mild weather will likely continue through Wednesday before another cold front arrives. The front could be accompanied by some snow flurries. Behind the front, it will turn colder, but the coldest anomalies will occur across Upstate New York and New England. The cold won't rival that of last week. Although the cold air mass will originate in northern Russia, that region has been experienccing near record and record warmth. As a result, the air mass will not be exceptionally cold when it reaches eastern North America. The guidance has accelerated the onset of rainfall on Friday. As a result, prospects for a record dry month have decreased. Nevertheless, Poughkeepsie and White Plains could still surpass their January records. Precipitation amounts through January 27th and January Records: Islip: 0.37" (Record: 0.51", 1970) Mount Pocono: 0.51" (Record: 0.61", 1990) New York City-Central Park: 0.45" (Record: 0.58", 1981) New York City-LaGuardia Airport: 0.35" (Record: 0.51", 1981) Newark: 0.34" (Record: 0.45", 1981) Philadelphia: 0.39" (Record: 0.45", 1955) Poughkeepsie: 0.12" (Record: 0.43", 1970) White Plains: 0.18" (Record: 0.44", 1955) Out West, Blythe, CA saw its record 300-day streak without measurable precipitation end today. The AO is now positive and is expected to remain predominantly positive through at least the first week of February. As a result, prospects for a 6" or above snowstorm in the New York City area will be limited. Since 1950, just 2 of 19 (11%) of storms with an AO of +2.000 or above during January 15-February 15 saw 6" or more of snow in New York City. Opportunities for a 6" or above snowstorm could persist for parts of southern New England, including Boston, through the first week of February. The ENSO Region 1+2 anomaly was -0.4°C and the Region 3.4 anomaly was -0.9°C for the week centered around January 22. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions are underway and will likely persist into the start of spring. The SOI was +11.22 today. The preliminary Arctic Oscillation (AO) was +2.467 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 100% probability that New York City will have a colder than normal January (1991-2020 normal). January will likely finish with a mean temperature near 30.3° (3.6° below normal).