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Any chance of El Niño during Atlantic hurricane season is almost gone

By Mark Sudduth
June 7, 2017 - 8:18 AM


Subsurface temperature anomalies along the equatorial Pacific as of June 2, 2017. Notice the lack of positive anomalies (yellow-orange-red) anywhere across the tropical Pacific. It’s mostly neutral for the time being.

Just looking at the most recent subsurface anomalies chart that was updated on June 2, we see that there is virtually no warm pool left in the tropical Pacific west of about 150 degrees longitude. The only positive anomaly, or warmer than normal area, is in the eastern Pacific and even here we’re talking about only a degree C at the most. To break it down in to simple terms: no El Niño anytime soon, if at all in 2017.

What does this mean for the Atlantic season? It means that we are likely to see less of the hurricane-inhibiting wind shear across the Caribbean and tropical Atlantic. That, in turn, should result in a busier season than we have seen in quite some time. It’s no guarantee as there are certainly other factors at play but the lack of El Niño is often seen as a significant enhancing signal for Atlantic hurricane activity.

We will get a new set of ensemble model plots from the ECMWF, which is often regarded as the model of choice, that will give us an update on its “thoughts” for the coming months. That model was quite aggressive in developing an El Niño going all the way back to the early winter months. We’ll see if it has seen the light, so to speak, and has backed off like other modeling has in recent weeks. I’ll keep an eye out for that new data and will include in during a future video discussion, so be on the lookout for that.

In summary, I think it is safe to say that El Niño will not be a factor this season and that, in and of itself, is reason enough to take the 2017 Atlantic hurricane quite seriously. We should be doing so any season but perhaps this time around, there may be more to it than normal. Time will tell.

http://hurricanetrack.com/2017/06/07/any-chance-of-el-nino-during-atlantic-hurricane-season-is-almost-gone/

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El Niño development pauses; ENSO Outlook remains at El Niño WATCH

Issued 6 June 2017 Next issue 20 June 2017

The El Niño–Southern Oscillation (ENSO) remains neutral. The Bureau's ENSO Outlook remains at El Niño WATCH, meaning there is around a 50% chance of El Niño developing in 2017—double the normal likelihood. However several indicators have shown little or no increase for several weeks, suggesting El Niño development has stalled for now.

Sea surface temperatures across the tropical Pacific remain warmer than average, though cooling has occurred in some areas over recent weeks in response to stronger than average trade winds. The Southern Oscillation Index has also eased to near zero values. All other ENSO indicators also remain neutral.

Four of eight international climate models suggest tropical Pacific Ocean temperatures may exceed El Niño thresholds during the second half of 2017, down from seven of eight models that were forecasting a possible event in April. Virtually all models have reduced the extent of predicted ocean warming compared to earlier in the year, indicating that if El Niño forms, it is likely to be weak.

El Niño is often, but not always, associated with a drier than average winter and spring over eastern Australia. If the tropical Pacific remains warmer than average, but El Niño thresholds are not quite met, some El Niño-like effects are still possible.
The Indian Ocean Dipole (IOD) remains neutral. Four out of six climate models suggest a positive IOD will develop by the end of winter. A positive IOD is typically associated with a drier than average winter and spring for southern and central Australia.

http://www.bom.gov.au/climate/enso/index.shtml