El Nino Southern Oscillation update

 

Today the Climate Prediction Center / NCEP released their weekly update.

Moving forward, I will likely be posting on the update every week right up to the coming winter. The post on the long range seems to be very popular. So, I will follow all y’all’s lead.  

Looking at the current Pattern involving North America.

We can see the trough developing out west, with ridging continuing to slide east into Thursday. 

Current Conditions.   

Yesterday's SST from NOAA Coral Reef Watch.  The El Nino signature definitely stands out.   But we can also see a lot of the northern Pacific is warm as well. But the north Pacific is nowhere near as warm as it was last year.

Today's SST from Tropical Tidbits

Nino 4 is at 0.1ºC, Nino 3.4 is still at 1.8ºC, Nino 3 is at 2.6ºC, with Nino 1+2 being the warmest at 3.5ºC

 

 The central Pacific equatorial region has been cooling off, while the warmer water that was there has been drifting eastward.  A couple of weeks ago, the SST in Nino 1+2 were at +2.9°C. All of this shows up in the following image from the Climate Prediction Center / NCEP.

Subsurface water temperatures in the east Pacific are becoming warmer deep down 500-600 feet. This will mean the SST off of Peru will stay warmer for most if not all of Winter 2026-2027

During September-November through November-January 2026-27, there is a greater than 90% chance of a very strong El Nino. 

 

Central based El Ninos (CP) have the warmest sea surface temperature anomalies over the central Pacific, extending out toward the date line. Eastern based El Ninos (EP) are considered more in the way of a traditional El Nino and have the warmer SSTs closer to South America.  The convection that has been over the Central Pacific is going to shift into the eastern Pacific; this will have impacts down the road.

The El Nino does seem to still be leveling off. So, this El Nino might not end up quite as strong as many have been thinking. But it could also remain a strong El Nino right through the upcoming winter.

As I’ve been saying the temperature contrast between the northern Pacific and the warmer-than-average waters in the eastern Pacific will shift the Pacific jet stream southward, steering more storms over the southwest and toward the Gulf Coast, Southeast. This will increase the risk for disturbances to move up the Coast, increasing the risk for inland runners and coastal storms for the Middle Atlantic into the Northeast.

Both the 1972-1973 El Nino and the 1997–1998 El Nino were east-based, while the 2015-2016 El Nino was central based. So, 1972-1973 and 1997–1998 look to be better analogues for the upcoming winter.