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#1477503 - 28/11/2018 10:40 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Sillybanter]
ColdFront Offline
Meteorological Motor Mouth

Registered: 29/06/2008
Posts: 19046
Loc: The Beach.
Originally Posted By: Sillybanter
So we could say its elino like conditions on the north side of the low and la Nina like conditions on the Southside. I don't see the need to reference ENSO every time a weather event occurs it the kinda sensationalism that drives the media these days. Its wet on the southern side and dry on northern side of a low and that is not new.The lows position is slightly odd for this time of the year but whats more unusual is that we have had several similar systems in a row dragging the dry air a little further east every time.

Originally Posted By: ColdFront
Originally Posted By: Sillybanter
I don't want to be inflammatory but El Nino doesn't really control the day to day weather in a sense does it. The lows over central Australia could happen in or out of an el Nino. SAM would have more of an impact on the current events I would have imagined.


Maybe and I don't see your post as inflammatory. However Livio Regano said he has not seen Lows that originated in the south of the country in November move so far north in his entire time at BoM and Retired Weather Man said he saw it last sometime back in the 50's so it's a fairly exceptional event.

Heatwaves and westerlies are certainly not unusual in any ElNino event but the placement of the Low would be very much so. Of coure we have not had an ElNino declared and as I have stated previously, the problem lies in the Indian Ocean. The crazy twist in the tail is that the same Low that dragged record heat over north eastern Australia just a couple of days back is drowning parts of NSW on its southern influence and its northern influence is fanning one of the worst fires seen in Qld.

The type of rain being witnessed in NSW is more typical of when ElNino typically decays.


It's not just the media that love to overstate things.
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#1477504 - 28/11/2018 10:41 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ashestoashes]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 3817
Loc: Buderim
Originally Posted By: ashestoashes
I wonder what influence this Ningaloo Nina has been exerting on our weather I feel like it's often under-appreciated. Since these conditions have been going on for a reasonable period of time.


Stronger Southerlies along the west coast. I think these are linking with the westerlies driven by Pacific warm water to drive westerlies across the top end. At the moment we have almost a pseudo monsoon pattern over Australia with the Ningaloo southerlies turning into westerlies bending around a low pressure trough.

I have seen hints that the summer lows may come further south than normal, while pressure over Darwin has been el nino like, and will presumably continue in the near future. If these patterns continue the tropics may have a weak start to the wet season, but there might also be a lot of moisture available driven into low pressure further south for heavy rain outside the tropics.


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#1477538 - 28/11/2018 12:44 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Mike Hauber]
Sillybanter Offline
Weather Freak

Registered: 17/03/2017
Posts: 58
Loc: Toowoomba
Massive amount of colder than normal water out there is certainly going to have a big affect on local weather patterns.
Would it be a stretch to suggest that the Gulf and NW Qld may do ok out of this type of set up. More moisture coming in from the NW rather than drifting west across the top end.
I will stick my neck out and make that prediction anyway. Poor buggers will probably get nothing now.

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#1477702 - 28/11/2018 18:35 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Petros Offline
Meteorological Motor Mouth

Registered: 30/12/2002
Posts: 8071
Loc: Maffra, Central Gippsland, Vi...
GFS's mooted tropical low over the Solomons over coming week should be a significant driver of westerly anomaly in the StormSurf's Kelvin wave generation zone?

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#1477704 - 28/11/2018 18:44 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Mike Hauber]
Petros Offline
Meteorological Motor Mouth

Registered: 30/12/2002
Posts: 8071
Loc: Maffra, Central Gippsland, Vi...
Originally Posted By: Mike Hauber
Originally Posted By: Petros
Whatever the ENSO state is, or is trending, look at the WV entering Aus via Pt Headland to Cairns atm!:



Keep in mind WV satellite shows water vapour in the upper atmosphere only. Substantially more water vapour is transported in lower level flows which do not show up on such satellites.


Noted, and was not aware of that.

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#1477707 - 28/11/2018 18:49 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Mike Hauber]
Petros Offline
Meteorological Motor Mouth

Registered: 30/12/2002
Posts: 8071
Loc: Maffra, Central Gippsland, Vi...
Originally Posted By: Mike Hauber
The last big Kelvin wave is now on its way out. The next one wont' be as strong, and with heat content back to average in the west I'd say that will continue to be the case and we're likely past peak heat content. Its also noticeable that the 20C depth is normalizing more than the overal heat content. The heat is still there, but its becoming shallower.



Have a look at the growth of the western subsurface cold pool in 97/98. For other el nino years the size of the subsurface cool pool doesn't seem to have a strong impact on next year's La Nina prospects, but I think in 97/98 the extreme size of the cold pool pretty much demanded that the next year would be strong La Nina. For other years I think it depends more on whether trades in Autumn tend to be more westerly or easterly.



....but at the surface?

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#1477708 - 28/11/2018 18:54 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Petros Offline
Meteorological Motor Mouth

Registered: 30/12/2002
Posts: 8071
Loc: Maffra, Central Gippsland, Vi...
Originally Posted By: ColdFront


East Coast Lows generally have much shorter lifetimes than tropical cyclones and last only a few days. They develop over the Tasman Sea close to the east coast and can intensify rapidly in the overnight period. Unlike tropical cyclones, where the warm seas provide the energy source, East Coast Lows are driven by a dynamic interaction between cold air in the high levels of the atmosphere over the continent, and the surface temperature gradient between the land and the relatively warm Tasman Sea air. They can produce gale to storm-force winds, very heavy rainfall and in some cases coastal inundation."


This Low originated in the Bight. It is not an ECL.


Classic cut-off low IMO.

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#1477716 - 28/11/2018 19:38 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Kino Offline
Weatherzone Addict

Registered: 10/08/2017
Posts: 3505
Loc: Wollongong, NSW, Aus
Definite cut-off, never developed on the Tasman Sea, was already developed. Just because itís on the east coast doesnít make it an ECL.

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#1477722 - 28/11/2018 20:07 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Petros]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 3817
Loc: Buderim
Originally Posted By: Petros


....but at the surface?




Atmospheric conditions have continued much as they have the last few months. SSTs cooled a little in the cooling part of the MJO cycle, but have recovered what they lost and still have at least some of the warming part to go, so overall the warming trend seems to be continuing.

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#1477724 - 28/11/2018 20:15 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 3817
Loc: Buderim
Most models still forecasting warm ENSO conditions for the forseeable future.


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#1477727 - 28/11/2018 20:30 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Kino Offline
Weatherzone Addict

Registered: 10/08/2017
Posts: 3505
Loc: Wollongong, NSW, Aus
That graph is a month out of date?

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#1477730 - 28/11/2018 20:46 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
ColdFront Offline
Meteorological Motor Mouth

Registered: 29/06/2008
Posts: 19046
Loc: The Beach.
I cannot see any dramatic cooling on the horizon to be honest.
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#1477733 - 28/11/2018 21:04 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
ashestoashes Offline
Weather Freak

Registered: 22/10/2017
Posts: 739
Loc: Voyager Point (South West Sydn...
All being said, this forecast for ENSO conditions is a fair bit of time away in weather timeframes. Also the austral autumn predictability barrier also prevents us from making a call.

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#1477736 - 28/11/2018 21:18 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
ColdFront Offline
Meteorological Motor Mouth

Registered: 29/06/2008
Posts: 19046
Loc: The Beach.
Agreed A2A. I was meaning through Summer.
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#1477769 - 29/11/2018 08:38 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 3817
Loc: Buderim
Typical rainfall pattern in a normal El Nino has a large increase in rainfall across almost the entire equatorial Pacific.



Typical rainfall pattern in a modoki el nino:



Note that from the dateline east there is no significant enhancement of rainfall. There is a peak enhancement just near the peak tip of Papua New Guinea.

Presumably cloudiness and rainfall have a close correlation.

Now look at the cloudiness pattern for the last 90 days:



Note a peak of cloudiness just near the tip of Papua New Guinea. This peak relates to the convective activity that has been driving the westerlies in this region over the last few months. Current cloudiness patterns seem to be a reasonable match for what is expected in a Modoki El Nino, however BOM measure cloudiness near the dateline, which is good for capturing the influence of a normal el nino, but misses the influence of a Modoki.

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#1477770 - 29/11/2018 09:08 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Long Road Home Offline
Meteorological Motor Mouth

Registered: 08/10/2007
Posts: 8802
Loc: Northern Beaches Syd
Just goes to show how inaccurate the seasonal outlooks are, Nov will likely come out very much above average across vast areas. It's only coastal QLD that have mainly missed out.





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#1477784 - 29/11/2018 11:52 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Mike Hauber]
Kino Offline
Weatherzone Addict

Registered: 10/08/2017
Posts: 3505
Loc: Wollongong, NSW, Aus
Originally Posted By: Mike Hauber
Typical rainfall pattern in a normal El Nino has a large increase in rainfall across almost the entire equatorial Pacific.



Typical rainfall pattern in a modoki el nino:



Note that from the dateline east there is no significant enhancement of rainfall. There is a peak enhancement just near the peak tip of Papua New Guinea.

Presumably cloudiness and rainfall have a close correlation.

Now look at the cloudiness pattern for the last 90 days:



Note a peak of cloudiness just near the tip of Papua New Guinea. This peak relates to the convective activity that has been driving the westerlies in this region over the last few months. Current cloudiness patterns seem to be a reasonable match for what is expected in a Modoki El Nino, however BOM measure cloudiness near the dateline, which is good for capturing the influence of a normal el nino, but misses the influence of a Modoki.


So OLR is acceptable to prove your theory on it being a Modoki (which BoM say no), but not acceptable to show that there is no coupling?

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#1477802 - 29/11/2018 13:15 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: ColdFront]
Mike Hauber Offline
Weatherzone Addict

Registered: 13/07/2007
Posts: 3817
Loc: Buderim
Yes that is correct. The OLR data is reflective of a Modoki pattern, and does not show that there is no coupling.

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#1477808 - 29/11/2018 13:46 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Mike Hauber]
Petros Offline
Meteorological Motor Mouth

Registered: 30/12/2002
Posts: 8071
Loc: Maffra, Central Gippsland, Vi...
Originally Posted By: Mike Hauber
Originally Posted By: Petros


....but at the surface?




Atmospheric conditions have continued much as they have the last few months. SSTs cooled a little in the cooling part of the MJO cycle, but have recovered what they lost and still have at least some of the warming part to go, so overall the warming trend seems to be continuing.


Pretty much agree, of note is the 16C isotherm near Galapo's has risen up to 95-100M below surface, after spending a couple of weeks nearer to 120M. Personally, I dont think the warm anomaly between 100M and the surface will have any impact on the surface at Nino1.2-East end of Nino.3 - coming week or two will tell.

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#1477813 - 29/11/2018 14:10 Re: Climate Driver Discussion 2018 (Enso, IOD, PDO ,SAM etc) [Re: Mike Hauber]
Kino Offline
Weatherzone Addict

Registered: 10/08/2017
Posts: 3505
Loc: Wollongong, NSW, Aus
Originally Posted By: Mike Hauber
Yes that is correct. The OLR data is reflective of a Modoki pattern, and does not show that there is no coupling.




Don't misquote me - if OLR is ok for you to rely on to postulate about Modoki, then it's also ok to rely on to demonstrate that there is no coupling, as per what the BoM have said. And you disputed, numerous times.

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