The Australian Weather Forum

Just thought I would start a thread on the main climate drivers to see what might be ahead for us. Here are the BoM reports from the latest model runs for Feb. Currently all signs are pointing to possible drought conditions by the end of 2017.

Hi JS it does seem to be looking like a drought. It is a bit hard to know what to think at the moment.
Summer hasn't lived up to its usual reputation around here, lots of cool nights, and days.
Very dry and dusty around here, about 75mls of rain so far, it is way too early for autumn,
but its looking like it now.
I think we might be in for a long boring, dry, year, hope not.
Hooroo Chris

Hawker wrote: ↑Sat Feb 18, 2017 12:51 pm Hi JS it does seem to be looking like a drought. It is a bit hard to know what to think at the moment.
Summer hasn't lived up to its usual reputation around here, lots of cool nights, and days.
Very dry and dusty around here, about 75mls of rain so far, it is way too early for autumn,
bit its looking like it now.
I think we might be in for a long boring, dry, year, hope not.
Hooroo Chris

Hi Hawker, certainly has been a strange summer. It will be interesting to see how the stats look at the end of summer. Max temp wise, nothing over 40 but I've had a good bunch of over 30. The lack of storms everywhere is the one big thing I've noticed.

Return of the dry... If it weren't for the modest dumps of rain that actually sink deep into the soil, it would be looking a lot worse.

I really hope we don't slip back into drought like conditions. But Melbourne always errs on the side of dryness, that's our climate. Even if an El Nino is weak, it will still have an impact here.

Don't forget the other important ingredient for Victoria - the AAO or SAM index, relating to the position of the westerly wind belt. Currently several models are hinting at a Negative AAO developing, which means an increase in low pressure systems moving further north towards southern Australia, which potentially means more rain bearing systems affecting us. Fingers crossed!

Geoff wrote: ↑Sat Feb 18, 2017 9:11 pm Don't forget the other important ingredient for Victoria - the AAO or SAM index, relating to the position of the westerly wind belt. Currently several models are hinting at a Negative AAO developing, which means an increase in low pressure systems moving further north towards southern Australia, which potentially means more rain bearing systems affecting us. Fingers crossed!

Definitely Geoff, I hope so. Do you have a long term model runs to share associated for SAM and AAO? I've only ever seen them run out to a couple of weeks to a month in advance.

The BoM's climate team are currently scratching their head's and trying to figure out how the upper westerlies have carved up the monsoon low's this cyclone season. Basically the negative SAM has smashed their cyclone season predictions so far which they believed was going to be above average. IMO is it almost certainly the reason for the lack of thunderstorm activity in Victoria over the past 6 months.

BoM has just released it rainfall outlook for Autumn 2017.

The usual go-to site for SAM outlooks is this one JS, which is an ensemble of eleven different models.....
http://www.cpc.ncep.noaa.gov/products/p ... _ensm.html
As you can see it only goes out to a couple of weeks or so, and the latest run shows it rising back into positive territory by mid March after a brief dip into the negatives early month.
The BOM POAMA model is another site worth keeping an eye on.
It seems the model outlooks are notoriously unreliable more than two weeks ahead.

Geoff wrote: ↑Thu Feb 23, 2017 5:06 pm The usual go-to site for SAM outlooks is this one JS, which is an ensemble of eleven different models.....
http://www.cpc.ncep.noaa.gov/products/p ... _ensm.html
As you can see it only goes out to a couple of weeks or so, and the latest run shows it rising back into positive territory by mid March after a brief dip into the negatives early month.
The BOM POAMA model is another site worth keeping an eye on.
It seems the model outlooks are notoriously unreliable more than two weeks ahead.

No worries Geoff, thanks. Yes, I only have ever seen the short term models. Will be interesting to see how they are looking in a month or so from now.

This is an interesting summary of the local summer 2016/17 and an autumn prediction; not directly related to this topic but probably the best fit? http://www.abc.net.au/news/2017-02-27/m ... ge/8306304

(Incidentally, note the discrepancy between the headline and what Scott Williams actually said )

Gordon wrote: ↑Mon Feb 27, 2017 10:20 pm This is an interesting summary of the local summer 2016/17 and an autumn prediction; not directly related to this topic but probably the best fit? http://www.abc.net.au/news/2017-02-27/m ... ge/8306304

(Incidentally, note the discrepancy between the headline and what Scott Williams actually said )

Yes Gordon, the media headlines always differ from the content within I certainly hope we don't slip back into a El Nino but there are definitely signs at the moment.

BoM have now moved into watch mode for El Nino

Equatorial Central Pacific Ocean isn't that interested in warming up yet (contrary to just about every forecast model of late): http://weather.unisys.com/surface/sst_anom.gif

StratoBendigo wrote: ↑Mon Mar 06, 2017 10:12 am Equatorial Central Pacific Ocean isn't that interested in warming up yet (contrary to just about every forecast model of late): http://weather.unisys.com/surface/sst_anom.gif

Good pick up SB - It will be certainly interesting to watch the next 4 weeks for any movement

Latest from NASA: https://www.nasa.gov/feature/jpl/could- ... -a-new-one

Just had a quick look at the oceans - IMO, El nino still a fair way off, SAM is going back to neutral so fronts may start coming up again by the start of May, IOD is still neutral but I have spotted some interesting temp changes in the last 7 days.

The Indian ocean has moved again towards an negative IOD position this week. Since the last snap on April 17th, Victoria has had a major NW rainfall influence.

All models except one still think a positive IOD in July but interestingly the BoM has now got it going negative.

Very interesting JS.

BOM have released their May-July 2017 climate outlook forecast today and they're still going for mostly dry and warm weather. I'm finding that hard to believe after their March 30 prediction of a dry April, and we ended up having the wettest April in 43 years!

The SAM (AAO) Index has gone strongly positive for the next two weeks, so looks like a drier than average first half of May could be on the cards.