bluewave

Still has an east based El Nino continuing in Nino 1+2 and 3 with strong WWBs by June. But notice how the CFS is much too cool currently in Nino 1+2. So we’ll probably have to rely more on the Euro which is closer to the current Nino 1+2.

Impressive how most of the weekends this year have had at least some measurable precipitation. Next significant storm appears to be set for Friday. But the way things have been going, we could have some lingering rain into early Saturday.

Even when we had our colder months from November to February, they were getting record +10 months in the West. So the geographic footprint of the cold was very small in the East. The shrinking size of the winter cold pools since the 2015-2016 super El Niño is part of the reason that 2025-2026 was our first colder longer term temperature winter since 2014-2015. Prior to the 2015-2016 winter, we would usually get a cold winter every few years. This was the first 11 year hiatus between cold winters. The chart below is for the entire Northeast which has been in the same boat as our local area.

We don’t know the specific details that far out. But the latest Euro continues the record WWBs at least into next March. This is why the model is trying to develop a 2nd Nino 1+2 warming peak near the end of the run like the CFS.

The first week of October finished near the warmest on record for the CONUS. The average for the CONUS from October 1-7 on Prism was 64.54° or +5.2°. So we’ll have to wait a while longer to get the final number. October 2026 through the 7th….64.54° +5.2° Top 7 Warmest October for CONUS 1963…59.34° 2024…58.93° 1947….58.50° 2016….57.45° 1950…..57.45° 2015…..57.24° 2021…..56.95°

Even though the CFS is currently too cool in Nino 1+2, the updated seasonal model update still has an east based El Niño lingering into next June with strong WWBs continuing.

October is continuing the seasonal model error for at least one month out. The seasonal models from early September had the typical -EPO October El Nino ridge near Alaska and NW Canada.This has been the seasonal model forecast error since May. The month to date has the 500mb ridge shifted further south over the CONUS with lower heights near Alaska. The next week will add to this pattern lowering heights more near Alaska and maintaining the CONUS ridge. This will be the furthest south ridge position for an El Nino October even when just using the 1972,1982,1997,2015, and 2023 super composite. Month to date Forecast through October 19th October forecast issued in early September October El Niño composite

Impressive PWATs near 2.00” with post-tropical Isaias and a decent pocket of MUCAPE. So probably a 1” to locally 3” event where the best banding sets up from Sunday into Monday. Pattern warms up for a few days following the storm with the big ridge expansion. Wednesday looks like the peak of this warm up. If the front is slower allowing enough sun, then the usual warm spots in NJ could see low 80s. Interior sections could see first freeze next weekend. So an active pattern for mid-October.

It feels like we have started to see non-linear shifts following these major heat releases to the atmosphere from the accumulated excess heat stored in the oceans. If you think about it we had a very similar climate from the late 1800s through about 1982. Sure there was some warming from 1885 to 1982, but nothing all that dramatic. Since the coldest winters of that era occurred in the late 1970s. Then the 1982-1983 super El Niño gave a slight bump to temperatures which remained about steady until 1997-1998. Following the 1997-1998 heat release, the greatest warming occurred in the Arctic several years later from 2005 to 2012. So the state of the Arctic sea ice shifted to much younger around 2007 and continues to this day in the same range. Then the next major heat release in 2015-2016 dramatically warmed our winters to the point that places like NYC only saw their next long term colder winter after 2014-2015 a full 11 years later in 2025-2026. The major climatic shift following 2015-2016 was the rapid warming and ridge expansion east of Japan beginning around 2018-2019 which has lead to this persistent record -PDO run. The heat release in 2023-2024 lead to the warmest CONUS winter to that point. 2025-2026 finished close to the warmest also but our little corner of the world finally got a cold winter after 11 years. But the geographic footprint relative to the rest of the CONUS was very small. It didn’t take away from the fact that it was an enjoyable winter for many here. Nino 1+2 never fully cooled off following 2023-2024 and gave us the Nino-like December 2024 with the record +PNA for a La Niña. Now this is the first time 2 El Niños this strong have occurred only 3 years apart. It feels like the big shift following 2023-2024 was a warming of the EPAC which had been the one region of the planet that had resisted the warming through 2022-2023. Many papers were written about the famous EPAC cold tongue. Now this current warming there has exceeded anything that has occurred in the past. This event into 2027 is going to be the greatest heat release to a higher baseline than all the previous events. So we don’t fully understand the shifts that will occur following this jump to a much warmer climate as we head into the late 2020s and then early 2030s. This EPAC warming since 2023-2024 in the chart below has been unprecedented.

Even the ONI wasn’t able to fully capture the full magnitude of the warming with the 2023-2024 event. Key Mechanisms and Findings Dual Warming Centers: Unlike typical El Niño events that center primarily in the eastern Pacific, the 2023–2024 event featured asynchronous double spatial peaks, combining a central Pacific peak (driven by zonal advective and thermocline feedbacks) with eastern Pacific warming. [1, 2] Synergistic Amplification: The dual Pacific warming centers worked together with an eastward-extended North Atlantic jet stream to amplify sea surface temperatures across multiple tropical basins.[1] Record Temperature Impact: Sea surface temperature anomalies accounted for roughly 92% of the interannual global warming spike, pushing the July 2023–June 2024 average global mean surface temperature to a record 1.58 °C above pre-industrial levels. [1]

A big question going forward is what does the future relationship look like in regard to the equatorial trade winds vs WWBs following such an enormous warm pool push from the WPAC to EPAC?

The Euro going into late winter and spring still has ENSO values warmer than any event had during the Nov-Dec peaks in the past.

Yeah, these “I” storms usually occur when the hurricane season is at its peak so it’s the most-retired letter.

Probably a secondary underlying factor overlapping with both ONI and RONI. Since we have had much stronger GOA lows in the past with similar RONI values. 1986-1987 had a much more expansive GOA-NP low than 2023-2024 with both RONI values near +1.5. Also note the much weaker GOA low in 2015-2016 than 1997-1998 despite identical RONI values of +2.3. My guess is this is a similar phenomenon we have been observing with all ENSO states. The 500mb ridges have become much stronger and expansive relative to the low pressure troughs. These stronger ridges have been driving the persistent -PDO and +AMO. So the warmer SSTs in the mid-latitudes are probably helping to cause a feedback loop. This area is outside the RONI band in the tropics.

RONI is not meant to be used for the absolute intensity of this event. It’s more about gradients and storm tracks. With something this historic, it’s the absolute temperatures and water vapor increase that matter which is better reflected by ONI.