Andrea Griffa
EF5
Yes I'm taking a look in this period and it seems that the pattern is changing into La Nina mode...See that:
ENSO Monitoring - A La Niña to boost the tropical season ?
Jim Bishop
EF4
I continue to agree that we are rapidly heading into a La Nina spring/summer. The only question in my mind is just how strong it will be. The latest models indicate a continued rapid decline in SSTs in the Nino3.4 region through the spring. Even though the mean solution brings us to weak La Nina by the summer, it's interesting that so far the more bullish models have been verifying better and suggest a moderate to strong La Nina going to the summer and fall.
Looking at the subsurface waters, I don't think a moderate to strong La Nina is out of the quesiton. Not by a long shot.
http://www.pmel.noaa.gov/tao/jsdisplay/
I also wanted to point out that based on research done by Dr. Gray at Colorado State, "La Nina increases hurricane activity (in the Atlantic Basin) & it makes it more likely to threaten the U.S. & Caribbean". I couldn't find the actual paper, but through a Google search I found numerous sites with the same quotes from Dr. Gray.
So while it's true neautral ENSO does enhance the hurricane season, La Nina does a bit more, and more importantly it actually increases the likelyhood of U.S. landfalls. That makes me wonder if the strength of La Nina correlates to anything, or whether it's strengthening or weakening during the hurricane season.
Looking at the subsurface waters, I don't think a moderate to strong La Nina is out of the quesiton. Not by a long shot.
http://www.pmel.noaa.gov/tao/jsdisplay/
I also wanted to point out that based on research done by Dr. Gray at Colorado State, "La Nina increases hurricane activity (in the Atlantic Basin) & it makes it more likely to threaten the U.S. & Caribbean". I couldn't find the actual paper, but through a Google search I found numerous sites with the same quotes from Dr. Gray.
So while it's true neautral ENSO does enhance the hurricane season, La Nina does a bit more, and more importantly it actually increases the likelyhood of U.S. landfalls. That makes me wonder if the strength of La Nina correlates to anything, or whether it's strengthening or weakening during the hurricane season.
Jim Leonard
As long as we have no El-Nino the chances are the tropical season across the atlantic basin should be above average in number and intensity. I've seen so, so seasons in La Nina years and real active during neutral years. The question on where they track all depends on where the longwave trough's and ridges setup toward the latter part of the summer. If the dreaded Hudson Bay vortex is in place which is there more than not. The majority of the atlantic tracks will be east of the U.S. coastline much like 1995. If we have a setup like 2004 and 2005 which are not very common the main trough will favor the western U.S. which would allow tracks into the southeastern coastline and Gulf coast.
During neutral and La-nina years the are many more hurricane tracks across the Caribbean sea.
During neutral and La-nina years the are many more hurricane tracks across the Caribbean sea.
Andrea Griffa
EF5
Is Nino coming back after a relatively little brief La Nina tendence?It would seem it is.
Jim Bishop
EF4
El Nino's not coming back, but La Nina isn't developing as quickly in the Central Tropical Pacific as I thought initially. It is developing rapidly in the Nino 1+2 region, however, and historically La Nina events develop from that region first and spread westward. Judging by the subsurface waters of -3C to -4C throughout the entire region, La Nina looks to be lurking in the coming weeks. But the above normal pocket of SSTs east of Indonesia and west of the Dateline seems to be keeping the weather pattern more indicative of a decaying El Nino right now (cool Eastern U.S.), even though it's been dead for a while. I would expect to see some big changes develop in the Nino 3.4 region by May.
Mark Sudduth
EF1
SOI and El Nino/La Nina
With the recent taking of the SOI, there was a pressure difference between Darwin and Tahiti- enough so that perhaps a brief westerly wind burst will set up and stunt the growth of this La Nina. Just a thought since the SOI did plummet for a time recently and is still negative. The longer it stays negative, the more westerly winds would set up- if I understand this correctly.
With the recent taking of the SOI, there was a pressure difference between Darwin and Tahiti- enough so that perhaps a brief westerly wind burst will set up and stunt the growth of this La Nina. Just a thought since the SOI did plummet for a time recently and is still negative. The longer it stays negative, the more westerly winds would set up- if I understand this correctly.
