ENSO

[ArtRosen]

Have we returned back to official La Nina or are we still officially neutral negative?

http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml has not updated.

[GaWx]

Have we returned back to official La Nina or are we still officially neutral negative?

http://www.cpc.ncep....ensoyears.shtml has not updated.

We're quite likely already within a weak La Nina,, but won't know for sure until after the fact because it takes five trimonths in a row of -0.5 or colder to be officially declared La Nina, retrospectively, at the posted link.

[Fred Gossage]

We do, however, have La Nina "conditions" present. The latest weekly numbers released indicate that ENSO Region 3.4 is down to to a -1.1C anomaly value.

[Bob Chill]

It will be interesting to see where the Nina bottoms out. The cfs has been the bull in the china shop. Last year averaged -1.4 through the season. I would be surprised if this nina comes in stronger.

Any quesses where we bottom out and what month it will be?

[tacoman25]

It will be interesting to see where the Nina bottoms out. The cfs has been the bull in the china shop. Last year averaged -1.4 through the season. I would be surprised if this nina comes in stronger.

Any quesses where we bottom out and what month it will be?

For a montly, I think the coldest will be December with -1.3. For trimonthly, NDJ with -1.2.

[GaWx]

It will be interesting to see where the Nina bottoms out. The cfs has been the bull in the china shop. Last year averaged -1.4 through the season. I would be surprised if this nina comes in stronger.

Any quesses where we bottom out and what month it will be?

I'm still going with a weak La Nina trimonthly bottom. My definition of weak is a bottom trimonthly of -0.5 to -1.0. I'm predicting a trimonthly bottom of -0.8 to -1.0, most likely including NDJ but maybe including surrounding trimonths. I'm guessing a weekly bottom of about -1.2 to -1.4.

[Bob Chill]

I'm still going with a weak La Nina trimonthly bottom. My definition of weak is a bottom trimonthly of -0.5 to -1.0. I'm predicting a trimonthly bottom of -0.8 to -1.0, most likely including NDJ but maybe including surrounding trimonths. I'm guessing a weekly bottom of about -1.2 to -1.4.

I'm thinking right along the same lines with you and tacoman. My thought process is pretty simple though. Just looking at the 50 history of tri monthly enso readings pretty much argue against a second year nina being stronger that the first. There are a few exceptions like 55-56, 75-76 (third year nina), and 99-00 but those years also featured -1.0+ readings for the months leading up to the winters. Not the case this year at all. We have been hovering around 0 to -.2 since april (tri monthly readings).

The cfs just wants to drop sst off the roof the next couple of months. Seems very unlikely at this point. If I had to take a guess @ ndj or djf readings I would think that -0.8 to -1.0 looks pretty reasonable. IMO -1.4+ seems very unlikely.

99-00 is an analog that has been tossed around alot but I don't think it is a good match. ENSO looks like a pretty good match but that year featured a +NAO and AO from Dec - Feb. The AO was +1 to +1.27 and the NAO was +.6 to +1.7. I guess we could end up with + nao/ao averages but there is a pretty good argument against it for the upcoming winters.

I've posted this in other threads but I think 62-63 and 67-68 could be good matches for the upcoming winter. I'm a weenie though so of course I like the cold look.

[JBG]

La Niñas are typically mult-year events. My guess is that the 1973-6 Niña is the best match and we are in year two, meaning this year will be weaker than last winter and next winter.