Will the North Atlantic sea surface temperature reach a daily record high before May 2026?
Resolved: No
Comments
skmmcj · on May 4, 2026
2025 was higher than 2026 for every day in February, 2023 was higher for every day in March and April. Resolves as No.
Haiku · on Mar 5, 2026
Prediction: 1%
I was at 5% on February 13. My analysis consists almost entirely of looking at the graph and doing a gut check on how weirdly the line would have to behave to get there, relative to the behavior of the other lines.
(A mathematical model would be nice, but I'm happy with my gut's approximation.)
kqr · on Mar 6, 2026
@Haiku A mathematical model agrees with your assessment.
Adonis · on Mar 7, 2026
@Haiku I was surprised to learn that many top forecasters here seemed to often predict similarly. I also did it a lot, and it's surprisingly effective if you build a good intuition, but recently I've been vibe coding a lot to make some math models, which I sometimes discard if my intuition tells me that the results look all wrong.
Russell-viper · on Mar 12, 2026
@Haiku The more you learn about the subject the more you realise that you know less. It's like a quote from Carl Richard, "Risk is what's left over when you think you've thought of everything".
exmateriae · on Mar 12, 2026 · (edited on Mar 13, 2026)
@Russell-viper @Haiku I'm not as confident (although I am pretty low) as in 2023, the temperature was lower at this point, and yet it would have resolved positive a few days before May!
Haiku · on Mar 12, 2026
@exmateriae Fair point! We did just 3 years ago get one of those rare sudden shocks. To my understanding, that increase was largely caused by the reduction of SO2 emissions from cargo ships. For this year, I think we'd have to see another even worse anomalous event.
A6N23 · on Feb 18, 2026
While 2026 started very warm, it is cooler than 2025 was at this time. Although 2026 is extremely warm, it remains below 2024 records of the same period. There is a "gap" of 0.3 to 0.4 which is quite large to overcome in the next 10 weeks and makes new records difficult.
The most likely scenario is that 2026 will finish as the 2nd or 3rd warmest spring on record.
Key Factors
- 0.3 to 0.4 gap to 2024 records
- Decreases Likelihood 10
Russell-viper · on Feb 6, 2026 · (edited on Feb 12, 2026)
Russell-viper's Prediction: 40%
The North Atlantic Ocean is the part of Atlantic Ocean situated to the north of the equator from North America to the west toward Europe/Africa. This region is famously known for violent waves and its storm-prone nature. It gets influenced by the warm North Atlantic Current, which is a continuation of Gulf Stream and brings warm water from the subtropics toward Europe which creates a milder climate in northwestern Europe.
Temperature representation of North Atlantic Ocean, ranging from 1 January 2026 to 10 February. (high quality GIF was too big to upload) Credit: C3S/ECMWF
Looking at the data Sea Surface Temperature (North Atlantic) for 2026 is below the peak set in preceding years but it's significantly above the 1991 - 2020 average. See the trend below.
Last year data released by Copernicus Climate Service (C3S) reveals that the parts of Northern Atlantic near France and the UK experienced a record heat in the month of August.
Source: ERA5, C3S/ECMWF
2024 was the warmest, followed by 2023 and then as we know now that 2025 was the third warmest year on record for both sea and air temperatures.
The background information section in the question mentions El Nino cycle, so I did some research on El Nino and La Nina.
Copernicus said, in 2025 the temperature rise dropped off marginally to 1.47C above pre-industrial levels, making it the third-warmest year on record at land and sea, This was due in part to the naturally occurring and cyclical Pacific Ocean cooling effect known as La Nina.
This statement makes sense to me as I think La Nina (cooling phase) on average is getting longer and stronger than El Nino (warming phase), maybe.
El Nino originates and develops in the tropical Pacific Ocean into Nino 3.4 region, not in the North Atlantic Ocean, and it develops when sea surface temperatures warm significantly in the central and eastern equatorial Pacific. It is declared when five consecutive 3-months running average of sea surface temperature (SST) anomalies in the Nino region 3.4 is above the (-0.5°C) and below the (+0.5°C).
El Nino literally starts in Nino 3.4 region and spreads east to Nino 1+2 and west to Nino 4. It's the exact area where the initial warming and the positive feedback loop starts.
(Nino 3.4 region is key for monitoring because anomalies here officially declare El Nino warm phase or La Nina cool phase and is used as the official monitoring and declaration region by NOAA, IRI.)
The development in the Nino 3.4 region has its effects on North Atlantic (SST) but it's indirect and operates with a lag and sometimes nonlinear. The strongest and most consistent El Nino influence on North Atlantic SST is a lagged warming during the decay phase of El Nino, peaking in March to May. This happens because the El Nino mature winter peak (Nov - Jan) teleconnects through atmospheric bridges leading to reduced trade winds, less evaporative cooling, and warmer Northern Atlantic 3 to 6 months later.
Currently, Nino 3.4 region is in a weak La Nina (cooling cycle) phase with 3-months running average remains in a weak La Nina territory which is -0.5C to -0.9C range.
Overall, the correlation is not perfect between developments in the Nino 3.4 region and North Atlantic SST but still, Nino 3.4 region drives global climate variability and is a science-based tool.
I think it is less likely to reach a daily record high before May due to the fact that last 3 years were unprecedentedly high. From 2023 - 2025, temperature averaged more than 1.5C above pre-industrial levels. Thus marking it the first time a three-year average exceeded this critical limit of 1.5C (that the nations agreed to stay below in Paris Agreement).
I think reversion to the mean is taking place with weaker La Nina in "Nino 3.4 region" as it's transitioning to El Nino and it operates with a lag (3 to 6 months) so this would make it less likely to exceed previous records.
Additional Comments
kqr · on Feb 11, 2026
Your first plot shows the "World" sea surface temperature, not "North Atlantic", which can be selected in the Area Selection dropdown.
Russell-viper · on Feb 12, 2026 · (edited on Feb 12, 2026)
@kqr i tried doing it but there isn't any option, they don't have a dedicated North Atlantic zoom or separate regional page, and it's https://pulse.climate.copernicus.eu/, not what i assume you're referring to, though i'll try to improve it.