donsutherland1

Parts of the region saw a dusting of snow overnight. The remainder of the day was mild with the temperature reaching the lower and middle 40s. Tomorrow will be a bit cooler with highs in the upper 30s. A storm tracking to the south could bring some snowfall to the region tomorrow night into Monday. The steadiest precipitation should pass to the south of New York City. Nevertheless, a 1"-2" snowfall appears likely in and around New York City. Lesser amounts are likely north and west of the City. Parts of central New Jersey and Long Island could see somewhat higher amounts. There remains a risk of lower amounts from New York City northward, as the City will be affected by the northern edge of a fairly weak system. Following the light snowfall, the remainder of Monday will see highs in the upper 30s and lower 40s. It will then turn milder for the remainder of the week into the beginning of next weekend. Highs will mainly be in the middle 40s. One or two days with highs in the upper 40s to near 50° are possible. The ENSO Region 1+2 anomaly was +0.3°C and the Region 3.4 anomaly was -0.5°C for the week centered around February 4. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.25°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely continue into at least late winter. The SOI was +20.94 today. The preliminary Arctic Oscillation (AO) was +0.006 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 95% probability that New York City will have a cooler than normal February (1991-2020 normal). February will likely finish with a mean temperature near 31.5° (4.4° below normal). Supplemental Information: The projected mean would be 3.8° below the 1981-2010 normal monthly value. Overall, Winter 2025-2026 is on track for a seasonal mean temperature of 31.9°. That would be the lowest winter mean temperature since Winter 2014-2015 when the mean temperature was 31.7°. Winter 2025-2026 would only become the fourth winter of the 21st century with a mean temperature of 32.0° or below.

Notice that the social media influencer posted a single water vapor map. That makes it difficult for readers to verify the accuracy of the claims being made. There is no reference point for comparison. Therefore, no structural validation is possible. But that's life on social media today where anyone can slap "wx" into their handle and then forecast. In fact, based on the 6z, 12z, and 18z cycles, the opposite has been true through the course of much of today. That's why the models have pulled back somewhat on the northern extent of the QPF and track of the relatively weak system. It will likely remain weak, as the environment is not conducive to phasing, as has been a recurrent theme over several days of 500 mb vorticity maps. The NAM, Icon, and GFS have all pulled back, with the NAM and Icon continuing their evolution through the 18z cycle. The 18z GFS has yet to initialize. With the 12z GFS having been above the consensus and the ongoing evolution of the synoptic environment, I wouldn't be surprised if its forecast is trimmed at 18z, though that's not guaranteed. Overall, taking into consideration the guidance, inter-cycle shifts in the guidance, and EPS individual members, a 1"-2" snowfall still seems reasonable for the NYC area and immediate suburbs. A strip of somewhat higher amounts could cut across central NJ and parts of Long Island. Overnight into tomorrow, I suspect that the guidance will begin to consolidate at a consensus.

I respect your precision. I used "explains" in a statistically descriptive sense, not to talk about causation. I could have used more technical language talking about measuring the predictable variation (via linear relationship in this case) between the independent and dependent variable(s). Keeping in mind that the Board has an audience, some of whom have yet to enter college, such terminology would create more confusion than clarity. Unfortunately, there are trade-offs involved in simplifying discussions.

Here you go: Winter State College Williamsport 1892-93 48.3 N.A. 1893-94 66.4 N.A. 1894-95 54.5 15.3 1895-96 33.7 31.5 1896-97 31.6 26.0 1897-98 40.2 30.8 1898-99 53.5 41.8 1899-00 27.0 15.9 1900-01 39.7 18.9 1901-02 59.9 60.6 1902-03 34.1 40.0 1903-04 39.1 49.7 1904-05 48.0 39.7 1905-06 30.7 30.4 1906-07 57.1 42.6 1907-08 67.8 54.2 1908-09 42.6 39.6 1909-10 66.4 35.6 1910-11 52.0 31.2 1911-12 45.5 35.9 1912-13 20.4 15.2 1913-14 77.4 55.4 1914-15 56.0 45.8 1915-16 48.7 65.0 1916-17 39.4 37.6 1917-18 60.5 62.6 1918-19 18.1 14.3 1919-20 54.2 41.9 1920-21 30.2 27.5 1921-22 41.9 32.8 1922-23 65.9 64.4 1923-24 42.2 27.5 1924-25 41.0 35.0 1925-26 48.3 43.0 1926-27 43.2 40.0 1927-28 64.8 38.1 1928-29 21.6 15.2 1929-30 24.0 18.0 1930-31 30.3 26.0 1931-32 28.4 24.7 1932-33 22.1 19.3 1933-34 31.1 37.0 1934-35 42.7 38.5 1935-36 72.4 48.9 1936-37 31.4 22.7 1937-38 20.2 20.6 1938-39 42.4 36.7 1939-40 49.5 44.3 1940-41 45.9 58.1 1941-42 75.0 39.8 1942-43 42.3 41.1 1943-44 36.4 23.6 1944-45 52.2 46.3 1945-46 29.5 34.3 1946-47 44.7 30.6 1947-48 42.5 40.5 1948-49 28.0 22.3 1949-50 34.5 36.8 1950-51 51.4 43.2 1951-52 41.9 50.2 1952-53 31.7 21.0 1953-54 34.0 28.8 1954-55 26.1 34.0 1955-56 32.7 45.4 1956-57 58.2 50.7 1957-58 57.6 49.1 1958-59 44.7 39.1 1959-60 47.8 51.9 1960-61 91.9 80.2 1961-62 52.2 49.6 1962-63 61.2 55.8 1963-64 78.2 76.2 1964-65 46.2 24.9 1965-66 43.2 39.1 1966-67 59.5 64.7 1967-68 30.9 29.0 1968-69 38.9 18.3 1969-70 89.9 82.6 1970-71 68.4 61.4 1971-72 54.2 59.5 1972-73 31.4 30.6 1973-74 40.9 40.6 1974-75 50.1 38.8 1975-76 42.9 28.9 1976-77 40.8 42.1 1977-78 98.2 83.6 1978-79 39.9 37.3 1979-80 17.9 20.5 1980-81 38.8 41.6 1981-82 69.1 54.5 1982-83 22.6 17.6 1983-84 50.2 40.7 1984-85 31.6 25.0 1985-86 42.3 31.2 1986-87 52.3 53.5 1987-88 39.0 36.8 1988-89 23.7 7.0 1989-90 40.8 31.3 1990-91 34.4 27.9 1991-92 26.9 20.0 1992-93 92.5 55.8 1993-94 109.3 81.2 1994-95 23.5 12.8 1995-96 99.0 85.9 1996-97 41.4 15.2 1997-98 48.2 31.1 1998-99 35.2 37.1 1999-00 19.8 23.1 2000-01 32.1 37.8 2001-02 21.7 19.4 2002-03 83.6 63.9 2003-04 71.4 55.5 2004-05 36.2 38.3 2005-06 26.9 25.0 2006-07 37.6 29.4 2007-08 43.2 31.1 2008-09 26.3 24.2 2009-10 49.1 34.9 2010-11 38.4 45.6 2011-12 19.0 12.3 2012-13 43.6 32.7 2013-14 51.8 45.9 2014-15 52.0 44.4 2015-16 17.9 7.7 2016-17 37.8 41.1 2017-18 34.1 26.8 2018-19 40.1 32.4 2019-20 13.2 13.4 2020-21 45.7 54.3 2021-22 31.9 29.3 2022-23 24.3 19.9 2023-24 22.0 18.1 2024-25 20.5 15.3

Warming winters coupled with unfavorable patterns/storm tracks are driving State College's seasonal snowfall lower. The coefficient of determination for the winter temperature-seasonal snowfall link is 0.498, meaning that the warming explains almost half of the decline in seasonal snowfall.

The 12z HREF: Deducting one category would still produce a 1"-2" snowfall for the New York City area and its nearby suburbs and a coating to an inch across most of Westchester and Rockland Counties. That is largely in line with the overall model guidance. I suspect that there will be an area with 2"-4" snowfalls in central New Jersey. The 12z NAM appears to be a high outlier overall.

Yesterday, the ECMWF-AIFS starting showing snowier solutions for New York City. Overnight, the guidance has shifted in that direction with the system taking a more northerly track than shown on the earlier guidance. Some of the overnight guidance such as the 2/14 6z GFS and ICON appear to have been overdone with the QPF for what is not likely to be a strong system. Those amounts will probably come down with subsequent guidance. Currently, it looks like New York City and its nearby suburbs are in line for a 1"-2" snowfall with higher amounts likely across central New Jersey. Areas north and west of New York City, especially from White Plains north and westward will see amounts fall off and perhaps rapidly. Most of the snow will likely fall prior to 9 am on Monday. Nevertheless, clouds could be slow to break holding temperatures to the upper 30s for most of the day. It remains possible that the mercury could reach 40° late in the day based on the 2/14 12z NBM. New York City could even see its first 40° or above low temperature since January 14th. Since recordkeeping began in 1869, New York City has seen measurable snowfall on 11.5% of years on February 16th. The highest daily figure was 9.9" in 1996. The most recent figure was 5.0" in 2010. The NBM presently shows a large spread between its 25th and 75th and 10th and 90th percentile figures. These large spreads convey a still high degree of uncertainty. A full-fledged February thaw still appears likely to crest during the middle and latter part of next week. There is fairly large uncertainty as to how warm the peak temperatures will get. 50s are possible in and around New York City.

Tomorrow and Sunday will see temperatures reach the upper 30s and lower 40s. A flurry or burst of light snow is possible in some areas tomorrow. A few areas could see a dusting. Some precipitation could arrive on Sunday or Monday. Areas with the highest probability of seeing precipitation will be south of New York City. A minor accumulation of snow is possible. It will likely become even milder with highs in the lower to middle 40s for a time next week. The ENSO Region 1+2 anomaly was +0.3°C and the Region 3.4 anomaly was -0.5°C for the week centered around February 4. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.25°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely continue into at least late winter. The SOI was +7.93 yesterday. The preliminary Arctic Oscillation (AO) was -0.519 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 94% probability that New York City will have a cooler than normal February (1991-2020 normal). February will likely finish with a mean temperature near 31.5° (4.4° below normal). Supplemental Information: The projected mean would be 3.8° below the 1981-2010 normal monthly value. Overall, Winter 2025-2026 is on track for a seasonal mean temperature of 31.9°. That would be the lowest winter mean temperature since Winter 2014-2015 when the mean temperature was 31.7°. Winter 2025-2026 would only become the fourth winter of the 21st century with a mean temperature of 32.0° or below.

A very good discussion, IMO. It describes what appears to be a reasonable worst-case scenario, although it should be noted that 4 EPS members now show 6" or more. It touches on the lack of phasing, which is a consistent theme given the wide separation of energy and front-running northern piece.

Today at the New York City Subforum: In reality, although the ECMWF-AIFS has brought back a moderate snowfall for Monday, the lack of ensemble support (at 0z), forecast temperatures, and its own unusual inconsistency over the past two days argues that its solution should be taken with a dose of skepticism. One should wait for additional support. For now, a light precipitation event remains possible. A moderate snowfall seems unlikely in the New York City area.

This is actually the highest number of days since Winter 2014-2015 (55 days). Winter 2020-2021 had 32 days.

The big weather story for the New York City area this weekend through the middle of next week will be the combination of a February thaw and relatively quiet weather. A weak system will likely pass to the south Sunday night and Monday perhaps bringing some light precipitation for a time, mainly to the south of New York City. Temperatures during any precipitation will likely be mainly near or above freezing. The thaw could crest on Tuesday with the high reaching the upper 40s and possibly 50° in Central Park. Beyond the five-day period, some showers or periods of rain could be possible on Wednesday or Thursday with the temperature remaining above freezing for the duration of the event. The five-day figures from the NBM: For context, the forecast averages are somewhat more range-bound and somewhat milder than the values for the overall 1991-2020 climate reference period. Exceptional warmth remains unlikely. Despite the upcoming thaw, February remains extremely likely to be colder than normal overall.

January 23-February 15, 1980 was exceptionally dry with just a trace of precipitation. There was some rain afterward, but it took until the first half of March to turn wetter.

As had been consistently the case with most of the high-quality guidance, the 500 mb story has remained largely unchanged. The spacing between the energy in the East remains too great to allow for much interaction, much less a phased solution. The top-performing ECMWF-AIFS has returned to its prior little or no snow solutions for President's Day. Finally, the overnight EPS deflated whatever dreams of a snowy solution might previously have existed.

Somewhat cooler weather has returned to the region. Temperatures will mainly top out in the middle to upper 30s tomorrow. The weekend will see highs in the upper 30s and lower 40s. It could become even milder with highs in the lower to perhaps middle 40s next week. Some precipitation could arrive on Sunday or Monday. The ENSO Region 1+2 anomaly was +0.3°C and the Region 3.4 anomaly was -0.5°C for the week centered around February 4. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.25°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely continue into at least late winter. The SOI was +7.93 today. The preliminary Arctic Oscillation (AO) was -0.731 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 93% probability that New York City will have a cooler than normal February (1991-2020 normal). February will likely finish with a mean temperature near 31.5° (4.4° below normal). Supplemental Information: The projected mean would be 3.8° below the 1981-2010 normal monthly value. Overall, Winter 2025-2026 is on track for a seasonal mean temperature of 31.9°. That would be the lowest winter mean temperature since Winter 2014-2015 when the mean temperature was 31.7°. Winter 2025-2026 would only become the fourth winter of the 21st century with a mean temperature of 32.0° or below.

The 5-day NBM temperature forecast for NYC is below. Next week will likely see the mildest weather so far this month move into the NYC area.

AI is advancing faster than its full and growing potential can be realized. Things could happen faster than I sketched and others may have a lot more insight. There’s also some risk of bottlenecks related to data center construction/expansion, sufficient power supply, etc.

The latest teleconnection forecasts have turned increasingly toward an AO+ as February moves into its final week. If these forecasts are accurate, the return of colder weather, albeit not severely cold, following the February thaw that remains likely through February 20 +/- a few days could wind up being fairly short-lived. If so, even if February ends with cooler than normal temperatures as suggested by the ECMWF weeklies, a milder regime could rebuild during the opening week of March. Forecasting skill for the teleconnections is fairly low beyond 10-14 days, so it will probably be another 5-7 days before one can be more confident about the outcome for the first week of March. Finally, the cooler weather with some opportunities for rainfall that will build into the Southwest by the middle of next week probably won't last more than a week. Warmer temperatures should return to close February.

Some further commentary in the wake of the ECMWF-AIFS's now consistently outperforming the ECMWF and Google DeepMind's rapid improvement in hurricane track forecasting on how I expect AI to transform the meteorological space over the next decade or two. My thoughts follow with the caveat that I do not possess a crystal ball. This is based largely on how AI has evolved very recently and the assumption that further improvements and integration with other technologies will occur. Prompt libraries executed by agentic AI would interpret/translate modeled outcomes at a local and even hyper-local street-by-street level, generate basic and customized maps/visualizations by tapping into Python and other programming libraries, disseminate a wide range of personalized information through Apps, etc. This will radically change existing value propositions. It would shift substantial value to the public and consumers/users of weather information. It would also upend business models based on charging for maps and graphics that are often based on freely available raw data simply due to the public's lack of access to the ability to generate such graphics on their own (programming knowledge to software). The evolution of AI would also dramatically change the nature of the meteorology profession from routine forecasting to communication of risk/uncertainty, mesoscale/microscale specialist, emergency response consulting, research, etc. I suspect that fairly routine things like 7-day forecasts, marine forecasts, hourly forecasts will be largely automated in a decade or two. Humans will focus more on communicating risk, identifying rare outcomes that could lie outside the AIs' training, advising proactive responses (evacuations, school closures/delays, etc.), and providing judgment in complex situations. AI would largely devalue the hype-based business models that have proliferated on social media to the detriment of professional credibility and public well-being, as the AI-driven outcomes available at little or no cost would be vastly superior to the hypecasters' products, services, and click-bait. Moreover, the AIs will allow users to verify the accuracy of the AI-driven forecasts enhancing credibility for the AI products/services. AI will also integrate large amounts of additional information to provide impacts assessments. AI will translate weather data into information concerning supply chain disruptions, energy demand, insurance exposure, traffic patterns, effects on crops, etc. These AI-driven impact models will likely be offered by major AI companies (Google, etc.) at much lower cost than under today's business models. That will also shift value to the AI companies who will be providing the service and the users of such information who will benefit from discounted pricing. Second order effects could also be unlocked for consumers of products/services (grocery prices, energy prices, etc.). In the end, this won't be the first time that technological change led to broad transformation. Almost certainly, it won't be the last time, either.

The ECMWF-AIFS is moving into it s high-skill range, where it continues to outperform the non-AI guidance. It continues to show very little prospect for the kind of occasional snowy solution that has popped up from time to time on some of the guidance. At 500 mb, its map tells the story about the low probability of phasing. The northern energy is well in front of the southern energy. This limits the risk of interaction, much less phasing. Not surprisingly, the other guidance now appears to be in line with the AIFS, with none showing a snowy solution for the NYC area. If one looks at the EPS ensembles, 16% showed 6" or more snow and fewer than 6% of members showed 10" or more snow during the 2/12 0z cycle vs. the respective 22% and 12% during the 2/11 0z cycle (in which the operational ECMWF showed a phased solution). Although it's premature to suggest that precipitation, should it arrive, cannot start as a little snow, sleet or mixed precipitation, the idea of a phased solution with significant snowfall appears unlikely. As has been the case much of this winter, should that outcome verify, the ECMWF-AIFS will again have led the way at an impressive lead time. Finally, the ECMWF-AIFS map 36 hours later shows a distinct failure to phase.

It will turn somewhat cooler to close the week. Temperatures will mainly top out in the middle to upper 30s on Thursday and Friday. The weekend will see highs in the upper 30s and lower 40s. It could become even milder with highs in the lower to perhaps middle 40s next week. Precipitation could arrive on Sunday or Monday. The ENSO Region 1+2 anomaly was +0.3°C and the Region 3.4 anomaly was -0.5°C for the week centered around February 4. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.25°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely continue into at least late winter. The SOI was -1.20 today. The preliminary Arctic Oscillation (AO) was -1.676 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 91% probability that New York City will have a cooler than normal February (1991-2020 normal). February will likely finish with a mean temperature near 31.5° (4.4° below normal). Supplemental Information: The projected mean would be 3.8° below the 1981-2010 normal monthly value. Overall, Winter 2025-2026 is on track for a seasonal mean temperature of 31.9°. That would be the lowest winter mean temperature since Winter 2014-2015 when the mean temperature was 31.7°. Winter 2025-2026 would only become the fourth winter of the 21st century with a mean temperature of 32.0° or below.

The April 1841 snowstorm was a really big one from parts of the Mid-Atlantic region into New England. Philadelphia received at least 8”. NYC picked up a foot. Some parts of New England saw 20”.

I agree. I think it's a statistical artifact, but can't rule out other factors being involved e.g., an increase in baroclinicity in early April that allows for occasional big storms even as the weather is warming. Interestingly enough, one finds a similar dearth of 6" or above daily snowfalls during March 23-31 in Newark where records go back even farther to 1843.

The operational ECMWF abandoned its call for a big snowstorm, but its AI cousin maintained continuity from its earlier cycles with its call for a lack of snow. FWIW, I've seen some complaints on social media concerning the EC-AIFS. They concern the model's being a "black box." At this point, given what I've seen, it's probably better that the AIFS is, in fact, a "black box," as it limits the ability of those who don't like what they see from injecting their own biases into the mix; a lot of that occurs when the non-AI model solutions are pulled apart (often yielding incorrect solutions from the injection of subjectivity). The AIFS has done quite well this winter, especially within four days. It has sometimes seen changes, but its run-to-run continuity is generally better than its non-AI counterparts, aside from its accuracy. This allows for longer lead time without compromising accuracy.

And its AI cousin says: