weak el nino to inhibit the 2006 hurricane season??

[willjnewton]

are the pressures high in the east pacific and is the trade winds normal across the eastern pacific???

[Matt-hurricanewatcher]

It looks pretty normal to me right now with a few area's slightly warmer then normal.

[willjnewton]

thanks matt hurricanewatcher and by the way does the eastern pacific if forecasted to stay normal???

[Matt-hurricanewatcher]

Yeah its running about normal right now...So expect about 15 to 16 named systems. Also its more or less a cell called a farrel cell which the warm air rises moves up to the tropause(Forms convection) the heat then spreads out. When it cools it falls again(Cool water) which forms kind of a high/higher then avg pressures. Then as the water rewarms this it rises again. Thats what I'v read into it.

This breaks down when a el nino forms in the warm water pushs eastward.

[P.K.]

Latest Tropical Climate Note from the BoM.

Weekly Tropical Climate Note

at 1300 CST Tuesday 1 August 2006

El Nino-Southern Oscillation Update
The 30-day SOI was mostly positive from September to April, with a few excursions above the standard deviation mark of +10. It peaked at +20 in mid-April. Following that it fell rapidly, reaching -10 by the end of May, and has since persisted at close to one standard deviation below the long-term mean. On 29 July it was -8, with contributing pressure anomalies of +1.4 hPa at Darwin and +0.1 at Tahiti. The official monthly SOI for June was -5, and its 5-month running mean centred on April was +3.

Early this year, the El Nino Southern Oscillation [ENSO] system was best described being within the envelope of neutral conditions, though it was bordering on a weak La Nina event. Since April-May, those conditions weakened. The climate system has since developed some weak El Nino type characteristics, but again within the bounds of neutral conditions. The SOI has been hovering around one standard-deviation below the long-term mean, and the heat content of the far eastern near-equatorial Pacific Ocean increased. Cloudiness over the northwest Pacific has been less than average for the early part of this northern hemisphere summer. Other interesting features of recent months include above normal cloudiness in the South Pacific Convergence Zone through to low latitude areas of eastern Indonesia. There is some hint that the warm anomalies of the sub-surface eastern Pacific Ocean may have peaked in June.

Shifts in ENSO state typically initiate during the southern hemisphere autumn to early-winter period. So far this year, there has been a slight shift toward El Nino conditions, but this has been weak, and there are no strong indications that it will continue further. Consistent with this, most available numerical and statistical models indicate neutral conditions will prevail this year. See the Bureau's "ENSO Wrap-Up" at http://www.bom.gov.au/climate/enso/, which includes links to a compilation of ENSO model predictions.

Intra-Seasonal Patterns
The near equatorial region of the central/western Indian Ocean has seen a periodic nature to the recurrence of broadscale convection, at a period of about 30 days, with the onset of active phases of convection seen around the middle of March, April, May and June, during the transition to the northern hemisphere summer. See http://www.bom.gov.au/bmrc /clfor/cfstaff/matw/maproom/OLR_modes/h.6.MJO.EQ.html. Some of these active phases were relatively weak, and earlier ones had little impact in the western Pacific. When the previous active phase was apparent over the northwest Pacific around late June, three systems reached tropical storm strength or greater [Jelawat, Ewiniar and Bilis]. Since then Kaemi also developed. Prior to this the region had seen a relatively slow start to the summer monsoon season.

If the recent short periodicity of the MJO had persisted, renewed activity would have been seen in the central Indian Ocean around the middle of July. Although convective activity did show a minor increase around this time, it was of relatively small scale, and did not progress to be a broadscale active MJO event. Over the past week or so though, there has been a general increase in organisation of the monsoon trough extending over Southeast Asia. It seems likely that this is the re-emergence of broadscale convection associated with a renewed active phase of the MJO.
http://www.bom.gov.au/climate/tropnote/tropnote.shtml

[Jim Hughes]

Today's Long Paddock daily SOI reading was a - 50.7. This is the strongest negative August reading they show and their daily records at their home page go back until the summer of 1991.

These type of extreme readings usually occur during late winter and early spring. Which of course is their summer and fall. So yes people the atmosphere is behaving like an El Nino is already here. But this does not mean that the ATL season will be a no show.

The moderate 2002 EL Nino started a little earlier in the year and it was still a fairly busy season but no where like some of the other recent years.

[willjnewton]

even though the soi is pretty impressive to some people wouldnt neutral conditions remain though???

[Derek Ortt]

Also its more or less a cell called a farrel cell which the warm air rises moves up to the tropause(Forms convection)

WHAT? The Farrel cell relates to the general atmospheric circulation. In the Farrel cell, the warmer air sinks and the cold air rises (sinks at the northern edge of the tropics and rises at the polar region boundary)

[Jim Hughes]

even though the soi is pretty impressive to some people wouldnt neutral conditions remain though???

It depends on who you ask and what you use for determination. If you mean NOAA then the answer would be yes because they are only going to use the 3.4 region's SST anomalies.

I am not to sure why everyone puts so much stock in NOAA's outlook anyway. Show me where they have good accuracy. And I am not talking about picking out one of the possible ten different models they use to show how one or two of them forecasted an event. You will always be able find a couple correct forecasts when you use so many different forecasting variables/ models. I WANT it written or said. Such and such is going to occur.

I have found over the years that their outlooks border on no more than luck and I am sorry if this sounds harsh but the proof is in the pudding. Just look at the past year. They did not forecast the weak La Nina this winter until it was already here and then they did not forecast it's demise. Which occurred almost immediately after they finally admitted that we had a La Nina present.

And now we have an EL Nino developing and several people have been forecasting it's development for quite some time now.

[wxmann_91]

Today's Long Paddock daily SOI reading was a - 50.7. This is the strongest negative August reading they show and their daily records at their home page go back until the summer of 1991.

These type of extreme readings usually occur during late winter and early spring. Which of course is their summer and fall. So yes people the atmosphere is behaving like an El Nino is already here. But this does not mean that the ATL season will be a no show.

The moderate 2002 EL Nino started a little earlier in the year and it was still a fairly busy season but no where like some of the other recent years.

I noticed that insane SOI reading this morning and was completely shell-shocked.

I agree that a weak-moderate nino is coming.

[willjnewton]

even though we have a el nino developing right now will it be very weak and NOT effect this upcoming hurricane season jim hughes???

[rainstorm]

https://www.fnmoc.navy.mil/products/NCO ... nomaly.gif

looks normal to me

[wxmann_91]

Look at the SST's below the surface rainstorm. One SOI reading does not equal a full blown El Nino.

[Jim Hughes]

even though we have a el nino developing right now will it be very weak and NOT effect this upcoming hurricane season jim hughes???

Some people , myself included, believe that the 2004 season was cut short by El Nino like conditions. At least compared to some other late season activity during the most recent heightened years.

So one could make a case that this season might slow down normally this year after the September-early October peak and the overall level might mimic 2002 somewhat.

There are other factors also though.

See some of my comments here about the AMO , and stratosphere. It was just a short recap of something similar that I wrote about at Storm2k last fall. That discussion was way....longer.


http://www.easternuswx.com/bb/index.php ... pic=102850

[willjnewton]

okay thankyou all for your answers, now I know that the eastern pacific is neutral and it will stay neutral for the next 1-2 months
so thanks

[Jim Hughes]

Look at the SST's below the surface rainstorm. One SOI reading does not equal a full blown El Nino.

This is not "one" daily reading here by any means. The 90 day average is approaching -9.0 . That is a legitimate average that is definitely pointing towards El Nino . The MEI is also starting to tilt that way. SST anomalies are warming , even Region 1+2 came around and the subsurface still supports this warm trend. What indicates a non event?

[wxman57]

I need someone to answer to this question please as I will read and learn
with very friendly people on storm2k but will a very weak el nino INHIBIT
the 2006 atlantic hurricane season???that's what I am very concerned about.


Thankyou so much for your responses

I remember reading a rather lengthy article in the Journal of the AMS a number of years ago that analyzed the relationship between El Nino/La Nina and seasonal activity. The author could only identify an inhibiting factor for a strong El Nino. Weak El Ninos had no recognizable effect on seasonal activity. Of course, a weak El Nino means no enhancing factor from La Nina.

[willjnewton]

I thought right now the eastern pacific is neutral Jim hughes??? I am confused

[Matt-hurricanewatcher]

Also its more or less a cell called a farrel cell which the warm air rises moves up to the tropause(Forms convection)

WHAT? The Farrel cell relates to the general atmospheric circulation. In the Farrel cell, the warmer air sinks and the cold air rises (sinks at the northern edge of the tropics and rises at the polar region boundary)

Ok I was thinking about the Hadley cell. Yeah the air sinks at 30 north then rises again at the polar front. That is why there lays most of the subtropical high pressure area's at 30 north. While the ITCZ is a converges zone between two streams of air.(Which has to do with the hadley cell).

The polar cell on the northern side sinks to form a polar high which converges when it lefts up the polar front at 40 to 60 north(Based on season).

[Jim Hughes]

I need someone to answer to this question please as I will read and learn
with very friendly people on storm2k but will a very weak el nino INHIBIT
the 2006 atlantic hurricane season???that's what I am very concerned about.


Thankyou so much for your responses

I remember reading a rather lengthy article in the Journal of the AMS a number of years ago that analyzed the relationship between El Nino/La Nina and seasonal activity. The author could only identify an inhibiting factor for a strong El Nino. Weak El Ninos had no recognizable effect on seasonal activity. Of course, a weak El Nino means no enhancing factor from La Nina.

So do you think the activity level of was 2002 was a fluke? The El nino was not strong and the activity level was defintely lower than other years during the past decade.