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#494445 - 09/01/2007 15:10 Re: I am backing another weak La nina
Johnoo Offline
Member

Registered: 23/11/2006
Posts: 8610
Loc: From: Where it forgot to Rain....
The 94-95 El nino also started weakening in January 1995 so it can be a fairly common occurnace.

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#494446 - 09/01/2007 18:03 Re: I am backing another weak La nina
Squid Offline
Meteorological Motor Mouth

Registered: 03/09/2005
Posts: 9535
Loc: Murgon
so it will probably be nutral conditions for the rest of the year?

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#494447 - 09/01/2007 19:07 Re: I am backing another weak La nina
Johnoo Offline
Member

Registered: 23/11/2006
Posts: 8610
Loc: From: Where it forgot to Rain....
Judging by the models especially POAMA model which is what BOM rely on the most Squid it looks like it will cool off the Pacific along the equator line in the central and eastern Pacific from now until March/April before theres a slight warming again just below El nino thresholds which will peak June/July period & then from mid-late July-August onwards it will slowly cool off again but all in all between March and August Nuetral conditions are expected mabye slightly warmer than normal particuly around May - July period but hopefully no renewal of the El-nino.
No sign of a La-Nina I'm afraid to say and looks like we will be without luck again this year 2007 about having one at this point in time, the most likely secario the Pacific will continue too cool until end of the year & stablise to right on Nuetral from October - December but alot can happen between now and then but if I were a betting man I would put no money on a La-Nina this year.

John.

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#494448 - 09/01/2007 19:16 Re: I am backing another weak La nina
Raindammit Offline
Weatherzone Moderator

Registered: 14/02/2002
Posts: 13363
Loc: Townsville & Bilyana NQ
I agree about hedging your bets on La-Nina toward the end of this year! The long term forecasting for El-Nino/La-Nina leaves a lot to be desired to say the least, with it being more of a 'now cast' rather than a forecast. Predictions seem to reflect what is currently happening, ie, the eastern pacific is cooling slightly so we are told 'El-Nino is breaking down' but if it warmed again in the next few weeks it would be 'El-Nino is strengthening' beyond that, no-one seems to be able to say with any sort of certainty say what the long term situation will be.

Looking at the latest ENSO outlook (which will be updated tomorrow) 7 out of 11 models are going for Neutral conditions by May, and 5 out of the 7 long term models are going for Neutral conditions by August.

:cheers:
_________________________
Belgian Gardens, Townsville NQ
Bilyana FNQ

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#494449 - 09/01/2007 20:16 Re: I am backing another weak La nina
AussieMark79 Offline
Member

Registered: 30/10/2005
Posts: 451
Loc: Lake Maquarie area, New South ...
there may be cool subsurface anomalites now but they are not really significant
compare that to this time in 1998

El Nino was in full flight but very cool subsurface temperatures were starting to appear this would later give birth to the 1998-2001 La Nina event

January 1998

January 2007

The cool we have now is nowhere near the intense cool we had in 1998

same as its not like the 1995 event

Decebmber 1994
April 1995

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#494450 - 09/01/2007 20:25 Re: I am backing another weak La nina
eternal rain Offline
Member

Registered: 10/07/2004
Posts: 5685
Loc: the great sydney desert
Yeah that current cool patch sure looks nice. Last time i saw one that good was probably early 2003. Sure is a good sign as it points towards the weak la-nina direction and the chances of an el nino restrengthening at this time of year are low but we also have to take into note that this current el nino developed in September which is unusual so anything could happen at any time of the year if u ask me. I was expecting it to weaken around June at least so im grateful to see it happening now, lets just hope she continues.

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#494451 - 09/01/2007 21:21 Re: I am backing another weak La nina
Squid Offline
Meteorological Motor Mouth

Registered: 03/09/2005
Posts: 9535
Loc: Murgon
thanks for the info john

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#494452 - 09/01/2007 21:42 Re: I am backing another weak La nina
AussieMark79 Offline
Member

Registered: 30/10/2005
Posts: 451
Loc: Lake Maquarie area, New South ...
there was a cool patch last year

January 2006

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#494453 - 09/01/2007 22:53 Re: I am backing another weak La nina
Johnoo Offline
Member

Registered: 23/11/2006
Posts: 8610
Loc: From: Where it forgot to Rain....
Quote:
Originally posted by AussieMark79:
there may be cool subsurface anomalites now but they are not really significant
compare that to this time in 1998

El Nino was in full flight but very cool subsurface temperatures were starting to appear this would later give birth to the 1998-2001 La Nina event

January 1998

January 2007

The cool we have now is nowhere near the intense cool we had in 1998

same as its not like the 1995 event

Decebmber 1994
April 1995
Looking at those maps of previous subsurface temps in previous weakening El-ninos we can see the 1997 event was very strong and equally as strong was the sub-surface cold water which was huge and much cooler than normal which expanded east to the South American coast & to the surface and we all know what happend (The La-nina of 1998-2000. As you can see the 1994-95 event the sub surface cold patch wasn't too large or strong at first either but later that year and 1996 there was a La-nina so as you can see it doesn't have to be a very strong El Nino to rebound and end up having a La-nina we can take heart from this that the moderate 94-95 El nino that it is possible that we can eventually end up having a La-Nina in the next 18 months I doubt it will happen this year but it is quite possible for 2008.


John.

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#494454 - 10/01/2007 03:33 Re: I am backing another weak La nina
*Runoff* Offline
Member

Registered: 24/01/2005
Posts: 2209
Loc: Whitsundays
We need that ice shelf to drift to the coast of Sth America. laugh

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#494455 - 10/01/2007 15:08 Re: I am backing another weak La nina
eternal rain Offline
Member

Registered: 10/07/2004
Posts: 5685
Loc: the great sydney desert
You can see on the January 2006 map that aussiemark posted the biggest problem there was that warm patch in the western pacific, which hogs all the activity from the east pacific and australia. But this current cold patch is taking advantage of the entire length of the pacific which is good to see:



Latest ENSO Wrap-up http://www.bom.gov.au/climate/enso/


Quote:
Summary: El Niņo showing signs of weakening

All the main ENSO indicators show that the El Niņo event has begun to weaken. This bodes well for a switch towards wetter conditions across Australia sometime in the late summer or autumn. The timing of the weakening also fits in well with that observed during previous events, although it is still possible for there to be renewed strengthening of the El Niņo event for a month or two before it finally dissipates.

Since late November, near equatorial sea-surface temperatures have cooled by about 0.1 to 0.4°C, cooler-than-normal sub-surface water has extended well into the eastern equatorial Pacific Ocean, with significant weakening of warm anomalies occurring as a result, and the Trade Winds have been stronger than normal across the western and central Pacific. Furthermore, monthly SOI values were neutral for both November and December and central Pacific cloudiness has been near to or slightly below average for almost a month.

However, a moderate to strong Madden-Julian Oscillation (MJO), with an associated westerly wind burst, is currently affecting the area between northern Australia and Indonesia. If the MJO maintains its intensity as it propagates into the western Pacific, a fall in the SOI, a decrease in the Trade Wind strength and an increase in cloudiness may occur as a result. This may cause temporary strengthening of the El Niņo event, but given the recent trends and the predictions from computer models, neutral ENSO conditions are expected to return during the southern autumn.
Ill be putting my bets on widespread heavy rainfall to occur in east NSW and QLD (not so much VIC) in late January/early Feb. Some memorable events in that time frame include the 2001 late Jan/early Feb NSW/QLD floods, 2002 late jan/early feb E NSW heavy rain, feb 2003 heavy rain in E NSW, late Jan 2004 NSW/QLD storms and late jan/early feb 2005 severe storms. Theres a better chance one of these patterns may repeat itself in this period if all goes to plan as you can see something has happend almost every year (apart from 2006).

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#494456 - 10/01/2007 15:39 Re: I am backing another weak La nina
*Runoff* Offline
Member

Registered: 24/01/2005
Posts: 2209
Loc: Whitsundays
I agree with everything you say Bokkey. It also appears a rossby wave is affecting the area just east of PNG. Effectively (hopefully) blocking the westerlies being borne out of the current MJO. History points to heavy rains ahead. The only downer is that after the 2001 event Queensland although wetter ,wasn't exactly saturated!

Victoria will most likely see their rainfall and an associated "cold winter" in the middle of the year.

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#494457 - 10/01/2007 15:55 Re: I am backing another weak La nina
Rainy Night Offline
Weatherzone Addict

Registered: 01/02/2004
Posts: 4267
Loc: Jindalee, Brisbane
It is interesting to note that the nex WZ Beta web-site includes "long range" forecasting, which provides a 28-day forecast for selected areas of Australia. The following quote is the text of the Sth East Qld forecast:
"Issue Notes
The hemispheric long wave pattern appears to be establishing a more stable pattern with 4 waves now predominating. However at present there are 3 main troughs currently located in the longitudes of the western Australia, just approaching South America and near South Africa. The fourth trough is near the Date Line. Consequently the highs and lows will continue to move in a more regular fashion over the next several weeks.
Summary:
Over eastern and southern Australia the major summertime cold front events likely to bring more widely spread rain are expected about 24-27 January, and 07-08 February. Events about 10-12 January, 19 January, 29-30 January and 18 February are likely to be limited to the more southern regions. Rain events originating in the tropics and moving south are possible about 01-04 January, 05-07 January, 25-27 January and 17-18 February.
Over Western Australia the strongest summertime cold fronts should occur about 08-09 January, 22-23 January and 05-06 February. Lesser events are likely about 14-15 January, 27 January, 30-31 January and 12 February. Rain events moving in from the north are possible about 03-04 January, 22-23 January and 15-16 February."

Perhaps the weakening of the el nino may have a positive effect on the predicted rain events 25-27 January and 17-18 February (predicted as originating in the tropics and moving south).
As mentioned by bokkey and runoff, there is a history of heavy rainfall patterns coinciding with the breakdown of el nino, and the dates forecast for rainfall events seem to be consistent with such a pattern.

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#494458 - 11/01/2007 07:29 Re: I am backing another weak La nina
Squid Offline
Meteorological Motor Mouth

Registered: 03/09/2005
Posts: 9535
Loc: Murgon
I foud this interesting a few weeks ago it was all blue in the coral sea now it is yellow very interesting to see how much the coral sea has warmed recently


http://beta.weatherzone.com.au/climate/indicator_sst.jsp?c=ssta

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#494459 - 11/01/2007 09:12 Re: I am backing another weak La nina
Rain Shadow (Fossy) Offline
Weatherzone Addict

Registered: 26/10/2006
Posts: 2756
Loc: Tamworth
Saw on the news the other night that the sea was very cool on Sydney beaches. Is that an isolated event or something to do with el nino dying? Please excuse my total ignorance guys.
_________________________
Silence is Golden,
but duct tape is silver

YTD. 828.0mm

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#494460 - 11/01/2007 11:16 Re: I am backing another weak La nina
Rainy Night Offline
Weatherzone Addict

Registered: 01/02/2004
Posts: 4267
Loc: Jindalee, Brisbane
During el nino events, the eastern Australian coastal waters (and that would include Sydney beaches) usually are cooler than average into the summer. If el nino is weakening, the sea temperatures there may warm to around average before too long.

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#494461 - 11/01/2007 12:43 Re: I am backing another weak La nina
Rain Shadow (Fossy) Offline
Weatherzone Addict

Registered: 26/10/2006
Posts: 2756
Loc: Tamworth
Thanks for that Rainy Night. Oh well I should do some more research on pacific warming and cooling. My knowledge is very limited to the SOI which I look at now and then.

When I lived in England I noticed that although it was very very cold, the atlantic ocean was always warm, so I guess it has the same affect there on weather as it does here, only the other way around.
_________________________
Silence is Golden,
but duct tape is silver

YTD. 828.0mm

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#494462 - 11/01/2007 12:50 Re: I am backing another weak La nina
*Runoff* Offline
Member

Registered: 24/01/2005
Posts: 2209
Loc: Whitsundays
The upper air is a lot cooler at lower levels above the UK. As is the lower air. Hence the feed off the warm waters falls as snow. I don't believe Elnino has much if any effect on that part of the world.

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#494463 - 11/01/2007 13:26 Re: I am backing another weak La nina
eternal rain Offline
Member

Registered: 10/07/2004
Posts: 5685
Loc: the great sydney desert
Sydneys water temps have nothing to do with el nino, its the NE'lys causing upwellings and something called Ekman shift. Theres a thread regarding that in the General weather section.

ps: squid, that does look interesting. Coral sea has exploded in terms of SSTs in the last couple of days. a low or cyclone cant be far away, same with some rain activity for the eastern parts of the country coinciding with that.

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#494464 - 11/01/2007 13:48 Re: I am backing another weak La nina
adon Offline
Meteorological Motor Mouth

Registered: 19/08/2004
Posts: 5338
Loc: Not tellin!
Geez coaral has warmed up That would have to have somthing to do with those good trades of late. Just hope that the warmer SST come down the coast a bit before a low/cyclone develops so that any rain might come into SE Qld and hopefully back into the inland.

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