ENSO Updates (2007 thru 2023)

[wxman57]

Sorry if I sound stupid but are we then saying everything considered and up to date we are looking at an enso-neutral for the majority if not all of this hurricane season?

That depends on what models you believe. The chart "Figure 5" in my post right above yours is not currently verifying. It's a forecast that dates back to mid March. Current SSTs in the Pacific are already warmer than most of the models on that graphic were predicting. NCEP ensembles predict El Nino conditions arriving during peak season. If nothing else, it could mean an abrupt halt to activity after September.

[jinftl]

From the May 7, 2009 update from NOAA...keeping in mind that there forecasts are not just based on model runs....they incorporate those into observations, trends, etc....that's what they get paid the 'big bucks' for...not just reading models, but preparing forecasts using all available data....

A majority of model forecasts for the Niño-3.4 region show that ENSO-neutral conditions will
continue through the remainder of 2009. The dynamical models, such as the NCEP Climate
Forecast System (CFS), increasingly favor above-average temperatures in the Niño-3.4 region, while
statistical models predict below- or near-average temperatures. Compared to the statistical models, the
dynamical models are more responsive to subsurface temperatures, which have recently increased as
positive anomalies have spread eastward. Based on current observations, recent trends, and model
forecasts, ENSO-neutral conditions are expected to continue into the Northern Hemisphere Summer.
http://www.cpc.ncep.noaa.gov/products/a ... sodisc.pdf

[wxman57]

From the May 7, 2009 update from NOAA...keeping in mind that there forecasts are not just based on model runs....they incorporate those into observations, trends, etc....that's what they get paid the 'big bucks' for...not just reading models, but preparing forecasts using all available data....

A majority of model forecasts for the Niño-3.4 region show that ENSO-neutral conditions will
continue through the remainder of 2009. The dynamical models, such as the NCEP Climate
Forecast System (CFS), increasingly favor above-average temperatures in the Niño-3.4 region, while
statistical models predict below- or near-average temperatures. Compared to the statistical models, the
dynamical models are more responsive to subsurface temperatures, which have recently increased as
positive anomalies have spread eastward. Based on current observations, recent trends, and model
forecasts, ENSO-neutral conditions are expected to continue into the Northern Hemisphere Summer.
http://www.cpc.ncep.noaa.gov/products/a ... sodisc.pdf

Nothing to disagree with there. But it looks like they're only taking the forecast out to the beginning of summer "into the Northern Hemisphere Summer" vs. through the summer. Question is, will El Nino develop by August/September as the dynamic models are forecasting? They do state that the NCEP dynamic models handle the warming subsurface water better than the statistical models. I think we'll see at least a weak El Nino by September.

[jinftl]

To build on your post....a legit question is what impact would a developing weak el nino have on the 2009 hurricane season if it does not develop until late summer/early fall..i.e., september plus or minus a month?

The infamous 2004 season had an el nino take effect in september of that season....in fact Dr. Gray lowered (and NOAA kept steady) their 'rest of season' forecasts in august 2004 because of it. We all know what happened next...the parade of florida storms.

Of course an el nino could deter tropical development, but a season that is neutral to start and only becomes truly el nino (using the definition, 3 months of variance +0.5C or higher in SST in nino region 3.4) towards the end just isn't the same as a season that is in an el nino phase from the start. Right now, there is no dispute we are in enso neutral.

From the May 7, 2009 update from NOAA...keeping in mind that there forecasts are not just based on model runs....they incorporate those into observations, trends, etc....that's what they get paid the 'big bucks' for...not just reading models, but preparing forecasts using all available data....

A majority of model forecasts for the Niño-3.4 region show that ENSO-neutral conditions will
continue through the remainder of 2009. The dynamical models, such as the NCEP Climate
Forecast System (CFS), increasingly favor above-average temperatures in the Niño-3.4 region, while
statistical models predict below- or near-average temperatures. Compared to the statistical models, the
dynamical models are more responsive to subsurface temperatures, which have recently increased as
positive anomalies have spread eastward. Based on current observations, recent trends, and model
forecasts, ENSO-neutral conditions are expected to continue into the Northern Hemisphere Summer.
http://www.cpc.ncep.noaa.gov/products/a ... sodisc.pdf

Nothing to disagree with there. But it looks like they're only taking the forecast out to the beginning of summer "into the Northern Hemisphere Summer" vs. through the summer. Question is, will El Nino develop by August/September as the dynamic models are forecasting? They do state that the NCEP dynamic models handle the warming subsurface water better than the statistical models. I think we'll see at least a weak El Nino by September.

[wxman57]

To build on your post....a legit question is what impact would a developing weak el nino have on the 2009 hurricane season if it does not develop until late summer/early fall..i.e., september plus or minus a month?

The infamous 2004 season had an el nino take effect in september of that season....in fact Dr. Gray lowered (and NOAA kept steady) their 'rest of season' forecasts in august 2004 because of it. We all know what happened next...the parade of florida storms.

Of course an el nino could deter tropical development, but a season that is neutral to start and only becomes truly el nino (using the definition, 3 months of variance +0.5C or higher in SST in nino region 3.4) towards the end just isn't the same as a season that is in an el nino phase from the start. Right now, there is no dispute we are in enso neutral.

I don't mean to imply weak El Nino = great news. JB pointed out similar years with a transition to an El Nino - 1965 (Betsy), 1969 (Camille), 1983 (Alicia), 1992 (Andrew). All those seasons but 1969 featured much lower numbers of named storms - only 4 in 1983. But it just takes one in the wrong location to make for a very bad season. A 2009 season with another Betsy-type strike and only 7 storms would be considered a disastrous season.

[jinftl]

Agree. I think at this point, all we can do is speculate on what factors we think may or may not lead to a 'busy' season. ENSO neutral/weak el nino is not very telling as far as what to expect....but as you say, it takes only one. Very rarely has a single community been struck by 2 monsters in a given season....all it took was one Camiille, one Hugo, one Andew, one Katrina, etc.

To build on your post....a legit question is what impact would a developing weak el nino have on the 2009 hurricane season if it does not develop until late summer/early fall..i.e., september plus or minus a month?

The infamous 2004 season had an el nino take effect in september of that season....in fact Dr. Gray lowered (and NOAA kept steady) their 'rest of season' forecasts in august 2004 because of it. We all know what happened next...the parade of florida storms.

Of course an el nino could deter tropical development, but a season that is neutral to start and only becomes truly el nino (using the definition, 3 months of variance +0.5C or higher in SST in nino region 3.4) towards the end just isn't the same as a season that is in an el nino phase from the start. Right now, there is no dispute we are in enso neutral.

I don't mean to imply weak El Nino = great news. JB pointed out similar years with a transition to an El Nino - 1965 (Betsy), 1969 (Camille), 1983 (Alicia), 1992 (Andrew). All those seasons but 1969 featured much lower numbers of named storms - only 4 in 1983. But it just takes one in the wrong location to make for a very bad season. A 2009 season with another Betsy-type strike and only 7 storms would be considered a disastrous season.

[wxman57]

Tropical Pacific continues to warm. Latest Australian model is even more bullish on an El Nino by mid summer with continued warming through the fall. This could diminish the chances of any/many late-season storms (past September).

[KWT]

They are starting to suggest a mod-strong El Nino towards the winter, but these models very often are over agressive when theyfirst latch onto a signal, seen it sooo many times.

Despite that feeling confident with the idea of El Nino by mid-late summer and as has been mentioned it may well shut down the later season.

[Bailey1777]

Shutting down after September does not seem like much of a shutdown to me. What is the break down if anybody knows of landfalling hurricanes by month?

[Bailey1777]

Shutting down after September does not seem like much of a shutdown to me. What is the break down if anybody knows of landfalling hurricanes by month?

[cycloneye]

In less than two weeks,after reaching in an upward way +10.3,since then,it has fallen like a rock to Negative values.When the SOI falls to Negative,it indicates warm ENSO spreading.

2009032820090426 10.3
2009032920090427 9.3
2009033020090428 9
2009033120090429 8.8
2009040120090430 8.6
2009040220090501 7.1
2009040320090502 7.3
2009040420090503 7.5
2009040520090504 7.6
2009040620090505 7
2009040720090506 5.6
2009040820090507 4.2
2009040920090508 2.7
2009041020090509 .5
2009041120090510 -.2
2009041220090511 -.8



http://www.bom.gov.au/climate/enso/soi.dt3

[Kerry04]

what does this mean for El Nino cycloneye?

[deltadog03]

adios amiga to la nina....she is all but about dead. SOI is truely showing the water warming and we are headed to perhaps a mdt nino by mid to late summer.

[cycloneye]

:uarrow: what does this mean for El Nino cycloneye?

Well,deltadog03 answered the question.

[Kerry04]

:uarrow: what does this mean for El Nino cycloneye?

Well,deltadog03 answered the question.

ok Thanks

[Bailey1777]

Can someone translate in detail how this would effect this season. More, less, areas that see more activity, how storms react, ect.

[Evil Jeremy]

Bailey, the peek of Hurricane season is in September, and many areas get hit during late August through October. This El Nino should start killing off storms around the end of August and in September I believe, and that will greatly reduce the chances of storms effecting places like Florida.

Then again, its hard to forget that 2004 was also an El Nino year.

[Bailey1777]

What is wild to me is how quickly things seem to be changing, 1 day it's totally neutral a couple days later a late season turn now a couple of days later a mid-season turn. Whats next the turn is starting now?

By turn I mean El Nino

[cycloneye]

It Keeps Tanking

2009032820090426 10.3
2009032920090427 9.3
2009033020090428 9
2009033120090429 8.8
2009040120090430 8.6
2009040220090501 7.1
2009040320090502 7.3
2009040420090503 7.5
2009040520090504 7.6
2009040620090505 7
2009040720090506 5.6
2009040820090507 4.2
2009040920090508 2.7
2009041020090509 .5
2009041120090510 -.2
2009041220090511 -.8
2009041320090512 -2.2




http://www.bom.gov.au/climate/enso/soi.dt3

[HurricaneBill]

Is it possible this could be as strong as the 1997-1998 El Nino?