CyclonicFury wrote:SFLcane wrote:Shell Mound wrote:Based on all available evidence, I think that at least weak El Niño conditions are likely to be in place by the peak of the 2018 Atlantic hurricane season. This would be sufficient to shut down the season. Additionally, any warming of the equatorial Eastern North Pacific would, regardless of the eventual ENSO state, increase shear in the Caribbean and MDR in 2018 vs. 2017, since equatorial Pacific SSTs will be warmer this year. There are too many opportunities, including the upcoming WPAC TC, for a coupled WWB to emerge, despite heat content being lower than in previous El Niño events. So, while any El Niño is unlikely to reach moderate or greater intensity, it should develop early enough to shut down the Atlantic. At least that's my view at this stage.
Um...Spring predictability barrier
I think it’s way too early to just assume we are headed for El Niño, especially since we still haven’t even exited La Niña and the
SPB comes into play. It’s also important to note that
a majority of models do NOT develop El Niño by ASO. There’s a medium to high chance we stay at warm neutral which would have little suppressing effect on the season.
I think the trend is what counts. At the moment are at the height of the SPB, yet trends—warming subsurface, WWB, upcoming TC genesis in WPAC (force multiplier)—are shifting toward El Niño. Also, the CFSv2 is trending warmer for ASO in recent runs and is getting closer to the ECMWF, which shows weak El Niño by peak season. If the trends were running in the opposite direction, I would agree with you, but neither the ocean nor the atmosphere is static. If current trends continue through April and early May, El Niño becomes certain or nearly so. Also, warm neutral ENSO, while not as unfavourable as El Niño, is substantially different from cool neutral ENSO, in terms of convective placement in the Pacific and overall impact on Atlantic, meaning increased vertical wind shear and less overall activity than in cool neutral years. Of course, what counts is the PDO, which influences steering currents, and El Niño is more closely associated with +PDO than other ENSO states, which, on average, weakens the subtropical ridge and reduces landfall impacts. So, while I do not totally disagree with you, I think the trends matter even during the SPB.