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the good news is in for the east coast!

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Created by Gestalt > 9 months ago, 5 Jun 2010
Gestalt
QLD, 14671 posts
5 Jun 2010 7:15PM
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ENSO Wrap-Up: Tropical Pacific neutral; chance of La Niña increases
Issued on Wednesday 26 May 2010 | Product Code IDCKGEWWOO

Climate indicators across the equatorial Pacific are currently neutral. Equatorial Pacific Ocean temperatures, trade winds, the Southern Oscillation Index and cloudiness over the Pacific are all at levels considered typical of neutral conditions (i.e. neither El Niño nor La Niña).

Historically, about 35~40% of El Niño events are followed by a La Niña within the same year. Currently, a large volume of cooler than normal water is present below the surface of the equatorial Pacific Ocean, which indicates that further cooling of the surface of the tropical Pacific is likely.

International climate models predict continued cooling of the Pacific Ocean sea surface, with the majority of models surveyed by the Bureau predicting that this cooling will be sufficient to see the development of La Niña conditions later in the year. No climate models suggest a return to El Niño conditions. It should be noted that correctly predicting transitional periods of the El Niño Southern Oscillation is more difficult than predicting the continuation or decline of El Niño or La Niña events.

nick0
NSW, 510 posts
5 Jun 2010 8:17PM
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so how is that good news for the east coast again?

under finned
NSW, 76 posts
5 Jun 2010 8:21PM
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I always thought we wanted to see el nino conditions on the East Coast to increase the strength and frequency of North Easterlies through summer? Always felt a bit guilty as it generally means drought and bushfires to the rest of the population, but I was dealing with it.....

Gestalt
QLD, 14671 posts
5 Jun 2010 8:31PM
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^ yeah, se ya later seabreezes,

but i prefer the cyclones, east coast lows and general strong SE winds.
so always look forward to la nina events.

KenHo
NSW, 1353 posts
5 Jun 2010 9:07PM
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Since it's been pissing down for the last 2 yrs, how are we not in a La Nina, and if not, does that mean it's all bogus anyway ?

Now, I have not followed this thing terribly closely, but on the few occasions I have taken notice of what the predictions were, they have been wrong.
That said, I'd love some more big southerlies thanks, but only after a cracking season of north wind !!!

PS I'm in considerable pain today after training a bit for my Maui trip, in case anyone is feeling unsympathetic and wants to bag me out for my trouble !!

Mobydisc
NSW, 9029 posts
5 Jun 2010 9:17PM
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May be good for Queenslanders but for NSW it means more wet summers with the usual doldrums. As Ken says, its was a wet and ordinary summer this year. There were decent seabreezes up till Christmas Eve but after that, bugger all until sometime in March.


KenHo
NSW, 1353 posts
5 Jun 2010 9:28PM
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Mobydisc said...

May be good for Queenslanders but for NSW it means more wet summers with the usual doldrums. As Ken says, its was a wet and ordinary summer this year. There were decent seabreezes up till Christmas Eve but after that, bugger all until sometime in March.





Not just NSW. When I was in Bundaberg in March, the rivers were all running brown with huge flood run-off, and Gin Gin in May looked like the garden of Eden, when it normally looks like South Dakota badlands.
I seriously could not see the cows in some paddocks because the grass was well over their heads, and farmers were slashing roads for them. Usually you can't see the buggers unless they stand side on and you squint to see through the dust and the heat haze.
If that's El Nino, I'm a vegetarian.

Gestalt
QLD, 14671 posts
5 Jun 2010 9:35PM
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yes, its been crap here also through that same period. this year up hear we barely got a SE wind to speak of. meant 2-3 months of poor winds not getting over 20 knots much. up here we don't see seabreezes much over 22 knots. but most SE winds are 20-30 knots.

the period we are all talking about was not la nina, it was el neno or neutral as shown by the graph



the last month has seen wind down south though.

the sst map below indicates higher temps in the areas that have bee ngetting the wind.



so la nina will see higher temps further up the east coast if it comes off an more chance of lows forming and driving in the wind.

anyone want to buy a 4.7m sail.

flipper4444
VIC, 1214 posts
5 Jun 2010 10:36PM
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what about the south coast my friend??

Mobydisc
NSW, 9029 posts
5 Jun 2010 10:45PM
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flipper4444 said...

what about the south coast my friend??


Gestalt
QLD, 14671 posts
5 Jun 2010 10:47PM
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^ i don't know what it means for the south coast during la nina. last la nina we had the WA crew had an ordinary season though from what was posted on seabreeze.

how has the last 2 months been for you?

flipper4444
VIC, 1214 posts
5 Jun 2010 11:01PM
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Gestalt said...

^ i don't know what it means for the south coast during la nina. last one we had the WA crew had an ordinary season though from what was posted on seabreeze.

how has the last 2 months been for you?


Our autumn in victoria has been really bad this year for wind.. This is our first week of wind that we have had for agers and i hope it stays this way

Gestalt
QLD, 14671 posts
5 Jun 2010 11:03PM
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this is what it means for south australia

Sea surface temperatures in the Pacific Ocean can affect rainfall right across Australia, but their most direct link is to rainfall in the eastern half of Australia.

The El Ni?o - Southern Oscillation (ENSO) is a major influence on Australia's climate, though its effect is less marked over much of South Australia than for areas further east.

ENSO is the oscillation between El Ni?o and La Ni?a conditions, interspersed with neutral periods.

These events are triggered by variations in sea surface temperature in the central and eastern tropical Pacific Ocean.

and the link -

http://www.climatekelpie.com.au/understand-climate/weather-and-climate-drivers/south-australia

plus this

www.bom.gov.au/lam/climate/levelthree/ausclim/ausclimsa.htm

Gestalt
QLD, 14671 posts
5 Jun 2010 11:27PM
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flipper4444 said...

Gestalt said...

^ i don't know what it means for the south coast during la nina. last one we had the WA crew had an ordinary season though from what was posted on seabreeze.

how has the last 2 months been for you?


Our autumn in victoria has been really bad this year for wind.. This is our first week of wind that we have had for agers and i hope it stays this way


if you look at the chart it's south australia and southern nsw that had high sea temps. i'm guessing both those areas got fairly good wind.

looking at the archived enso charts victoria looks like march may have been good if my theory works. but i can't find the chart for feb to check further.

the charts are here.
www.bom.gov.au/climate/search/enso-wrap-up.shtml?bookmark=no-rm

gunna
SA, 162 posts
6 Jun 2010 12:45AM
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last 2 months not memorable,typically autumnish,the odd windy day.
our wind at the moment is from cold fronts-sthwestlys and high pressure systems creating northerlywinds--if the centre of the highs sit around central aus we usually have good northerlys--if they sit lower we dont.
rule of thumb here is in winter,if we have good weather,sunny skies,you have crapp conditions in qld,ie--plenty of wind.--and vice versa

Gestalt
QLD, 14671 posts
6 Jun 2010 1:38AM
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^ i might need to go back to the drawing board then.

typically up here a high means no wind also. only along the edge where it pushes against a low do we get any wind.

i was working on the theory that the higher sea surface temp anomilies would intensify low pressure systems meaning more chance of wind and stronger cold fronts with more thunderstorms associated.

then after the front passes you get colder sea surface temps from upwelling.

maybe that only happens in the tropics.

but none of this is related to la nina, i kinda posted 2 threads in one.

and the third thread is that i'm reading some stuff that the fishing should be better after the bad weather has passed because of upwelling which is indicated by cooler sst's.

KenHo
NSW, 1353 posts
6 Jun 2010 8:22AM
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The big thing here is that looking at factors like ENSO, and sea surfaces temps etc, is to try and predict weather at a "complicated" level, much like a car at rest. It's a complicated mechanism.
However, weather is not complicated, it is "complex", like a car in motion, where the parts of that complicated mechanism starts interacting with each other and the surrounding environment.
Weather is also an emergent system, meaning, that even though it is governed by a consistent set of rules, there are so many rules interacting with each other, that you have to run the system to see what will actually happen rather than be able to predict what will happen.
Smarter people than me have defined about 3 days as the limit before predictive models start disintegrate in the exponential explosion of permutations and combinations.
Put more simple it's like trying to shoot charlies when playing pool. Looks simple, no-one has ever done it.


Gestalt
QLD, 14671 posts
6 Jun 2010 5:39PM
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what about down south?

so i did some more research and it appears that it's the opposite to what i was thinking. around south OZ positive SSTA's indicate lighter winds and negative SSTA's indicate stronger winds. that's the opposite to what we get up here.

http://www.bom.gov.au/events/9icshmo/manuscripts/PM_B6_Watterson.pdf

the main controlling factor for weather around south australia is the SAM. positive sam usually accompanies positive SSTA's in the mid latitudes.

for good frontal systems to the south a negative SAM is better. that includes new zealand also.

the SAM controls the position of the frontal line in the mid latitudes. positive sees the frontals roll through in the southern ocean with highs over South australa/victoria and negative sees them roll through higher up over south australia victoria with highs over the southern ocean.

www.niwa.co.nz/news-and-publications/publications/all/wa/14-2/sam

so to see what the weather is most likely to produce look to the SAM charts. i think this is mainly a winter setup also?

www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/aao/aao_index.html

victoria weather. www.climatekelpie.com.au/understand-climate/weather-and-climate-drivers/victoria

sand point and a negative sam would be good most likely.

Carantoc
WA, 7177 posts
6 Jun 2010 7:33PM
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And I thought it was just about those red and green arrows.

I think I may be a bit simple because the most I can understand is if the arrows show red then it definitely isn't any good and if the arrows show green then it probably isn't any good


Gestalt
QLD, 14671 posts
6 Jun 2010 11:38PM
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^ that works too.

i like to see ahead further than 1 week so trying to understand the bigger picture helps.

last time i used my 4.7m sail was during a la nina season and with another one possibly on the way the 4.7 will get use again. i've even bought gear based on long range forecasts in the past. i was going to buy a sup but if the la nina holds true i won't bother.

who knows what's going to happen in the end.

there should be lots of wind around vic around the 18th and from july to march in SEQ should be fantastic but of course it may not.

Carantoc
WA, 7177 posts
6 Jun 2010 9:45PM
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Do you record what days you sailed and what it was like to compare forecast with actual ?

Or do you just sort of remember each time and draw a general conclusion.

Would it help if everybody recorded where they sailed and what board / sail size they used ?

Is that too anal, or giving away too many secrets, or just a waste of time ?

Gestalt
QLD, 14671 posts
7 Jun 2010 12:13AM
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Carantoc said...



Do you record what days you sailed and what it was like to compare forecast with actual ?

nope. but i did once compare synoptic archive charts against recorded gps/weather records to try and understand what produces good seabreezes in SEQ. the results were confirmed after doing more reading.

Or do you just sort of remember each time and draw a general conclusion.

when it comes to windy seasons i remember whether it was la nina or el nino. i'm not talking about the day a storm came through but more a general increase or decrease of wind over a seasonal period.

Would it help if everybody recorded where they sailed and what board / sail size they used ?

probably not. all of the data is already available online that identifies the indicators to what the weather will do from previous data analysis. you can also look at the archives on the bom site to check things further and see where the strongest wind and direction is from for a specific area. but others have already done it and made it available.

Is that too anal, or giving away too many secrets, or just a waste of time ?

yes it's anal. i am not trying to interpret weather maps and come up with some new theory on things. i'm just trying to understand what scince has already discovered and understand it. computer models are predicting outcomes and i am looking at those outcomes. if the models are wrong then so am i. what i have noticed in the past is the models aren't out by that much generally.

surfers do the same thing to get the best swell, skiers do it also to get the best snow when booking trips etc.




it's been interesting for me finding out what makes the weather down south tick. i never really understood winter weather patterns in SEQ, why some seasons have good westerlies and other seem to have more southerlies. all of my focus has been trying to understand cyclones, local seabreezes etc.

KenHo
NSW, 1353 posts
7 Jun 2010 8:15AM
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I've always noticed that if it is a wet autumn, then it tends to be a mild winter, implying fewer strong south westerly winds
Last year as an example.
Does that gel with things ?

albers
NSW, 1739 posts
7 Jun 2010 8:51AM
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Cold water surface temperatures, especially during summer, will possibly increase the number and intensity of NE seabreezes.

A seabreeze, I believe, is supposedly caused by the temperature differential between the temperature of the land and the temperature of the sea.

As the land temperature increases during the day, the heated air above it rises and is replaced by the cooler air over the adjacent sea. The greater the temperature difference between the land and the sea, the stronger the breeze.

Sydney, over the last 20 years, has experienced warmer sea temperatures, as well as warmer over night land temperatures (Heat Island effect). Since the land temperature starts the day higher than it did previously, less air will rise than if the temperature were lower. Add to that a warmer sea temperature and we get an overall reduced temperature differential between the land and the sea, and therefore, reduced sea breezes.


Gestalt
QLD, 14671 posts
7 Jun 2010 10:54AM
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KenHo said...

I've always noticed that if it is a wet autumn, then it tends to be a mild winter, implying fewer strong south westerly winds
Last year as an example.
Does that gel with things ?


i got nothing.

i can't answer that. there is a lot of research currently going on into the relationships between inter seasonal weather patterns. but it's early days and i don't know what the outcomes are.

the 2 big drivers of autumn rainfall in SEQ are the indian ocean dipole and la nina, both would bring warmer moist air i think which mixes with fronts and troughs and causes rain. how that relates to winter i don't know. the timing of the start of la nina or a negative dipole would be more important i would think.

this guy http://web.maths.unsw.edu.au/~matthew/swwa_rainfall.htm has recently done some studies and seems to be indicating there is a connection. indicating that droughts over SW WA would mean cold winters in SEQ. but i could be interpreting that wrongly.

the la nina and indian ocean dipole are seasonal patterns and the SAM is a shorter 14 day cycle. so you could have multiple +ve and -ve SAM's in a season. it's probably the combination that increase or decrease rain fall.

i guess.

are there any meteorologists out there?

Gestalt
QLD, 14671 posts
7 Jun 2010 11:06AM
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albers said...

Cold water surface temperatures, especially during summer, will possibly increase the number and intensity of NE seabreezes.

A seabreeze, I believe, is supposedly caused by the temperature differential between the temperature of the land and the temperature of the sea.

As the land temperature increases during the day, the heated air above it rises and is replaced by the cooler air over the adjacent sea. The greater the temperature difference between the land and the sea, the stronger the breeze.

Sydney, over the last 20 years, has experienced warmer sea temperatures, as well as warmer over night land temperatures (Heat Island effect). Since the land temperature starts the day higher than it did previously, less air will rise than if the temperature were lower. Add to that a warmer sea temperature and we get an overall reduced temperature differential between the land and the sea, and therefore, reduced sea breezes.





i once tried to figure out a wind strength versus temperature difference relationship to see if i could predict how strong a seabreeze would be. i didn't get to far with that. it seemed more important where the highs to the SE of australia are positioned. looking at the gps/wind records it became apparent thate a strong high over new zealand produced stronger seabreezes in SEQ as more moist air was pushed into the east coast trough line and there is reduced cloud cover to allow the land to heat up.
there is also a really good page at the bom that describes the effects of NW winds on seabreezes.

http://www.bom.gov.au/nsw/amfs/Sea-Breeze.shtml
www.bom.gov.au/nsw/amfs/More-on-Sea-Breeze.shtml


KenHo
NSW, 1353 posts
7 Jun 2010 11:24AM
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And the biggest SE winds come when there is a low up north and a high down south just touching at the edges. THe area at that conjunction really gets windy !!
We used to get that in Bundaberg a bit, and it produced a lot of wind.
One year, I sailed small gear every day for over 3 weeks.
Maybe that year or the next I used a 4.0 over 20 times in a late summer/autumn period.

Gestalt
QLD, 14671 posts
7 Jun 2010 12:10PM
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^ yeah, bring it on!

KenHo
NSW, 1353 posts
7 Jun 2010 12:29PM
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Gestalt said...

^ yeah, bring it on!



That's the sort of conditions you need to really get Burrum Heads hammering for some really huge speed times.

Gestalt
QLD, 14671 posts
7 Jun 2010 2:45PM
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the last 2 burrum events we have missed out on cyclones by 2-4 weeks or there abouts. both were la nina and el nino years so it will happen in time.

the big difference was that this year the SE winds didn't kick back in after the cyclone passed where as the previous year they did. whether that is directly related to enso i'm not sure.

with the green island week, it is a guess but if we do get a la nina this winter i would think the chances of good winds are a lot higher. maybe

these are all of the computer models that are collated to figure out enso trends. becasue they are forecasting the eastern side a drop on the graph is reflected by an increase over here.



link iri.columbia.edu/our-expertise/climate/enso/

KenHo
NSW, 1353 posts
7 Jun 2010 3:42PM
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Just before that cyclone event, someone on here posted that a cyclone is often followed by a windless period. I recall thinking they had been right.
A big clonic stirs up a lot of cool water sometimes, if it sits in one place.
I remember a whopper out near Fiji that just sat there and died in a puddle of coolwater of it's own making.
I would also take cyclones out of the usual modelling, because they say more about specific conditions conducive to low formation than they do about highs.
Conditions vary a lot over a relaively short distance too. When I was in Bundaberg, I asked the locals what sorts of northerly season they ahd, and they said it was pretty ordinary. That contrasts pretty strongly with the great season we had a few hundred km away.



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"the good news is in for the east coast!" started by Gestalt