bluewave

Was nice to so see a forecast rainfall axis actually shift east over time like the models started doing a few days ago.

Will be interesting to see if Newark can sneak in one more 90° day to make it to 40 before the season ends. Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Jan through Dec Click column heading to sort ascending, click again to sort descending. 1 2010 54 0 2 2022 49 0 - 1993 49 0 3 1988 43 0 4 2021 41 0 - 2002 41 0 - 1991 41 0 5 2016 40 0 - 1983 40 0 - 1959 40 0 6 2025 39 116 - 1994 39 0 - 1944 39 0 7 2005 37 0 - 1987 37 0 8 2018 36 0 - 1949 36 0 9 2015 35 0 10 1961 34 0

While many spots still have a significant rainfall deficit over the last year, it was nice to get just over 1.00” here since yesterday.

DC used to average more than 20” of snow a year. So their snowfall has been in steady decline for years now. The much lower bar allowed DC to reach near average this year at 14.9”. DC missed out on the snowy 16-17 and 17-18 seasons further north. So this is the first 9 year stretch there with under a 10” average. If your average snowfall eventually gets low enough, then it can be easier to reach the new lower average with one storm. That’s why the further south you get in the U.S. the easier it becomes for one storm to get you closer to the new lower snowfall averages. In a cutter, hugger, and suppressed Southern Stream storm track regime for Philly to Boston, sometimes the DC area can get a snow event which gets suppressed south of the Philly to Boston I-95 corridor. Makes sense that the long term snowfall decline is more pronounced around DC since they are further south where it’s warmer with more marginal temperatures to begin with.

The reason the Euro seasonal snowfall forecast worked out from Philly to Boston is that the storm track matched the seasonal forecast. So it didn’t really matter for the snowfall outcomes that the overall forecast for DJF was too warm. Since the colder conditions than forecast last winter came in behind the warmer storm track.

But the storm track matched the warm winter pattern it was forecasting. The composites below are for the 20 days that .20+ of precipitation fell from Philly to Boston. The average temperature at Philly to NYC on these days was in the low 40s. So it was too warm for much snow with the storm track to the west of the I-95 corridor. The Euro seasonal precipitation forecast had above average near the Eastern Great Lakes matching the warmer storm track which verified. Plus there was major flooding in areas like West Virginia along this storm track. The Southeast ridge on the days when the wettest storms occurred was even more amplified than what the general seasonal forecast from the Euro was. Plus the warm departure on the heaviest storm days was significantly warmer than the seasonal temperature forecast. So in effect a warmer version of the seasonal forecast did occur through the storm track. The Pacific Jet was too strong and warm for much snowfall from Philly to Boston relative to the means. This has been a common theme leading to the record low snowfall near I-95 since 2018-2019.

It was the warm storm tracks from Philly to Boston that resulted in the very low snowfall. Very strong Southeast ridge and Pacific Jet on the days when most of the precipitation fell. This has been the main theme since 2018-2019.

The much below average snowfall forecast from the seasonal models run during the fall of 2024 from Philly to Boston did work out. They even got the very low snowfall correct for Chicago. That’s what most on here follow anyway. A continuation of the warm storm tracks through the Great Lakes theme.

It’s good to see some areas doing this well with these big Pacific Jet extensions in recent years. Looks like the strong -IOD forcing lead to the jet extension and wave breaking event. Record warmth in Western Canada with record high 500mb height anomalies. Then the record low 500mb heights over the Western Great Lakes leading to the very early snowfall.

The Great Lakes snowbelts continue to be the best spots for snow in recent years.

Same summer pattern with heaviest rains staying just inland from the coast with .39 here.

Too bad we don’t currently have the technology to determine the exact timing for the break up of the WAIS. Since it could lead to an unexpected faster sea level rise. More rapid melting at some point in the coming decades could become one of the big stories even for people that don’t pay much attention to the warming climate. https://www.nature.com/articles/s41586-025-09349-5 Human-caused climate change worsens with every increment of additional warming, although some impacts can develop abruptly. The potential for abrupt changes is far less understood in the Antarctic compared with the Arctic, but evidence is emerging for rapid, interacting and sometimes self-perpetuating changes in the Antarctic environment. A regime shift has reduced Antarctic sea-ice extent far below its natural variability of past centuries, and in some respects is more abrupt, non-linear and potentially irreversible than Arctic sea-ice loss. A marked slowdown in Antarctic Overturning Circulation is expected to intensify this century and may be faster than the anticipated Atlantic Meridional Overturning Circulation slowdown. The tipping point for unstoppable ice loss from the West Antarctic Ice Sheet could be exceeded even under best-case CO2 emission reduction pathways, potentially initiating global tipping cascades. Regime shifts are occurring in Antarctic and Southern Ocean biological systems through habitat transformation or exceedance of physiological thresholds, and compounding breeding failures are increasing extinction risk. Amplifying feedbacks are common between these abrupt changes in the Antarctic environment, and stabilizing Earth’s climate with minimal overshoot of 1.5 °C will be imperative alongside global adaptation measures to minimise and prepare for the far-reaching impacts of Antarctic and Southern Ocean abrupt changes.

Looks like a back and forth pattern setting up this month. Next chance for low 90s at the usual NJ warm spots Friday into Saturday. Then cooler weather returns for next week with a warm up again in mid-September.

The big story in the Arctic last few summers has been the record warmth in the Kara and Barents seas areas with the very low sea ice extent there. https://alaskaclimate.substack.com/p/august-2025-arctic-sea-ice Regional Sea Ice The Atlantic side of the Arctic has had very low ice extent all summer, with the Barents and Kara Seas almost entirely open water for much of late July and August. The pack ice edge at the end of August was near 82N, 200 km or more north of the Svalbard and Franz Josef Land archipelagos. The climate impacts of the lack of ice were dramatic. The only real-time climate station in Franz Josef Land, Polargmo Im. E. T. Krenkelja on Heiss Island at 80.6N, did not record a temperature below freezing in August. At Wiese (Vize) Island, a small island in the northernmost Kara Sea at 79.5N, the temperature has remained above freezing since July 16 (47 days as of September 2). Last summer, the longest freeze-free period there was 11 days and in summer 2023 the longest was only 4 days. On the Pacific side of the North Pole, ice loss in the Beaufort Sea increased during August, but plenty of ice remained at the end of the month in the eastern part of the basin. The Northern Sea Route, along the north coast of Russia, was open to most vessels by late August. The Northwest Passage, connecting Canadian waters with the Bering Strait, was close to being open for non ice-hardened traffic, but mobile areas of higher concentration ice persisted at the end of August in Amundsen Gulf, the southeastern-most portion of Beaufort Sea.

The one lucky thing about that hurricane is that the surge occurred at low tide. So the actual tide level was similar to Sandy. But the surge was higher than Sandy which happened right at high tide. The rapid forward motion of the hurricane allowed the water level at the Battery to rise 13 feet in around an hour. Can’t even imagine what that would have been like in the era before weather forecasts. https://www.nature.com/articles/srep07366 While Hurricane Sandy was record breaking compared to published tide gauge records, earlier historical accounts suggest that a major hurricane in 1821 CE may have had a similar storm tide and a substantially larger storm surge5,7. During this 1821 hurricane the New Bedford Mercury newspaper reported a rise in water of 13 feet 4 inches or 4.06 m above low water in the East River4,6. The 1821 hurricane struck New York City at low tide with roughly 4.0 to 4.1 m of storm surge, compared to Sandy's 2.8 m of storm surge. Assuming this account is referenced to near the Battery, a 4.0 m storm surge would far exceed all events recorded within the instrumental tide gauge record, including Hurricane Sandy. Other flood descriptions support the 1821 hurricane as a significant flood event, including a 10 foot (3.0 m) rise in water level at Pungoteague, VA5, drift caught in the trees 9 feet (2.7 m) above the ground at Cape May, NJ5 and a tide several feet above normal at New London, CT6. Because peak flooding for the 1821 hurricane occurred at low tide, its storm tide was smaller than its overall surge. Ref. 7 estimated a storm tide of roughly 3.2 m for the event, which is slightly less than that observed for Hurricane Sandy at 3.4 m.

This is the strongest -IOD since the 22-23 and 16-17 La Ninas. My guess for the rest of this season is that the ACE will finish below the 161 level of last year. But we have to watch for a rebound in hurricane activity from mid to late September right into October which has been common since 2012.

Strongest -IOD in 3 years.

Looks like Friday into Saturday will be our next chance for 90° heat at the usual warm spots. Could be some scattered convection with the cold front. But should become cooler and drier into next week as Canadian high pressure dominates again.

First two consecutive years with a quiet Labor Day weekend following a Cat 5 hurricane.

It comes out before the NOAA maps but has been reasonably close based on recent experience to what the NOAA updates have been. The state of PA had their 3rd warmest June and July period on record at 71.8°. The summer ranking will be lower when NCEI updates in a few weeks since August was cooler.

It will probably come down to frontal timing. The GFS has 90° on Friday for the warm spots in NJ. The Euro has a slightly slower frontal passage so the 90° on Saturday. Won’t take much to beat guidance by a few degrees with how dry it has been.

The August maps won’t update for several more days on that site. But the summer maps on some other sites that have updated are the same pattern. Warm in the East and West with cooler in the middle. The prism maps already updated for JJA with numerous top 10 warmest summer rankings for the Northeast.

The main reason I use it is that my analysis and forecasts are based on the perspectives. So I need to compare it to what has happened in the period of record. But I understand that many seasonal forecasts are 1991-2020 departure based on where the areas of above and below temperatures are located. My guess from several years back that our next colder winter would only be colder relative to the much warmer 1991-2020 baseline worked out. As this past winter in the Northeast would have been slightly warmer based on earlier periods of record. DJF 2024-2025 Northeast 24.6° 1895-2000….+1.4° 1961-1990……+1.8° 1971-2000……+0.5° 1981-2010…….-0.3° 1991-2020……-1.2°