The charts for later in the week point to low level snow fall in the South Island.
Yes it looks like being unseasonable again from Thursday throught he weekend. If the prognoses are correct, then it will be unusually intense and prolonged for a cold spell in December, especially following the cold outbreaks of 25/26 November and this weekend. How often has it snowed on Dunedin hills in December? In Canterbury, I remember visiting Chch on 2 Dec 1991, when there was a dusting on the top on Mt Herbert, and light flurries on the upper plains, so low-level snow this month is not unheard of, but rather unusual anyway.
I asked my mum when it snowed on christmas day and it was in 1975 at Mt white station, were they had white out conditions which lasted a couple of days.
Mt white station borders the Arthers Pass national park
It looks that anticyclonic conditions will settle in way to the south of Australia in the coming week. A shallow low pressure system over SE Australia looks to nestle itself into the cradleing anticyclone, eventually weakoning it but the weakoning and stationary anticyclone will still be strong enough to be able to manage to send cold southerlies over NZ through and into the We.
There is a good chance of thunderstorm activity within the Cold SW flow because of heating/on shore flow etc. which results in instability
We'll have to wait and see
Air will be coldish upstairs for this SW period you mention John but not going to -25. I see it getting no colder than -20. I guess it could be enough. I want to see some good temps and dewpoints for some development!
Location: Rainy Manurewa, Auckland - "City of Gales"
Unread postby Michael »
Just batten the hatches again don your scarf and raincoat prepare to buy plenty of brollies as they will be wrecked by the wind if they havent sold out and we may get a white Xmas
Latest MetService long-range doesn't mention snow, but the latest ECMWF has isobars extending all the way to Antarctica from Thursday to Sunday. (though with a southwest flow over NZ, so Canterbury may or may not feel the full impact)
You can tell there is a small bit of instability out there with small Cu type forms popping up. I think it's going very light NE here in Southshore to.
Lots of altocumulus castellanus forms going up with some good Cu to. Not sure what it'll do, a bit too late in the day perhaps. I'm pretty sure it's NE here but it's still registering SW at Templeton and Hilmorton so perhaps a small convergence?
Tomorrow could give birth to a similar situation and with a southerly meant to come through who know's what'll happen? John?
yeah Aaron I think something might be going up outside I got some good dark bases with some good CU and a few anvil tops out here.
Also may I add I have just had the most huge drops of rain which I took a few pics of which you can look at later its basically drops believe it or not the size of a 20 cent pieace something you would only see on the west coast it does sound not possable but when u see the pics you will know.
John Aaron whats going on out there?.
By the way on the forecast tonight they did say sumthing about heavy showers along the east coast with the change but nothing when it was on CHCH forcast for tomorrow.
cheers
JASON TIPPET.
yeah wow I think there's a very small storm buster out there heading towards Kaikoura it's really strange because I had a few quiet distant thunder rumbles here but no lightning that's when I thought storm buster like the boxing day one of 2003 except hardly developed yet .
Not sure what is happening out there some nice CU its very strange clouding over but slowly becoming darker the clouds and that's not just because of the darkness falling.
It was more like 10 cent peices instead of 20. Tenty cent peices would be too big for what I was getting even that was big it also returned again as well between last post and now.
So here's a few photo's below to show you iam not exadorating (phew big word) and one of some CU.
Its a bugger its dark can't get any good pics but if there's lightning let it be.
Cheers
JASON TIPPET.
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Yeah I must admit it was pretty strange I only heard a few rumbles so It could have easily been a plane in the distance as they tend to fly around the coastline but I was so caught up in the idea because of the huge drops of rain it took me by surprise when I heard it but it remains a mytsery .
Ohh well be intersting to see what this quick southerly flick tomorrow will bring us proberly just showers. .
Cheers
JASON TIPPET.
I'm thinking there's a chance of something happening today as the edge of a upper pool of cold air hugs Canterbury (-23/-22C 500mb). We have a NE now with an ok dewpoint of 7C, and a good temp of 17C. With the change we could get something? Tot tot are in the 50's over us to for 1pm. This high cloud isn't the best but the temp at the surface seems to be doing well.
Perhaps only heavy showers in the foothills as Metservice eluded to yesterday in their outlook? A slightly higher dewpoint would be better. Wait and see.....
Vertical velocities aren't the best but are negative over the Canterbury area. CAPE is only around the 20 mark but I feel this is wrong due to the surface temp and dewpoint being higher than what the model is suggesting, this will result in larger CAPE values, I think? Lifted Index isn't great either on the model but higher temp's and dewpoints at the surface now means things will be more negative than the model suggests, I'm not sure what this'll be though.
Temps is still rising and dewpoint has now gone to 8C. High cloud is also breaking up letting the sun in. A bit of cumulus to the south to....
It's 18.9 at Jeffs but the slightly more exposed Templeton and the airport are only registering around 16.5C due to a light S. Still, something to watch eh!
I think the ones your talking about are AVN charts that I used. I haven't been able to pull those up for a while now as things (server's) are going out and my links aren't working for one of those particular models anymore. I don't know which server to use now for those type of maps.
There is the READY system of which TonyT has tolled me about and is what I now use as I can't seem to get onto the other ones:
Just type in NZCH (for Christchurch) or NZAA (for Auckland) into that "ICAO or WMO ID" box then click on "Interactive map" for charts showing the temps etc or pratically anything (LI or CAPE, you name it). You could also try the "Sounding" one which is for forecasted skew t's. The good thing is you can overlay two feilds which is cool.
Some nice CU developing over the Plains and smaller out towards the SE.
Will be intersting to see what happens a nice light NE wind here and a temperature of 17.8dg.
Met Service is looking at afternoon/evening for showers so that maybe might give time for some good development and some good sun in.
Cheers
JASON TIPPET.
There looks to be a Cb on the plains out behind or over Oxford with it's anvil spreading eastwards, some big Cu near it to. No lightning from it yet though according to the tracker.
Cu development over B'sP hasn't got anywhere.
I also note in the latest model run CAPE has been increased due to more surface temp etc. I suspect it's more than the currently progged 40.
Edited: 1:55pm
Strikes now on the tracker, despite being registered far away it will be from the Cb I mentioned above. Perhaps the strikes are weak?
Edited: 2:25pm
Strikes now beginning to fire up out to the NW with some strikes closer to Chch. Jason, much out your way? Not intense but something!
Edited: 2:33pm
Yes, it looks as if the storm is in an area behind Oxford, Lees Valley or there abouts.
Last edited by Thunder on Tue 07/12/2004 14:33, edited 1 time in total.
Yes, Aaron, I am picking up a few sfreics looks like unfortunately to the N/Nw of here towards maybe inland North Canterbury. A bit hazy as well.
The wind was SW at work ay Halswell and when I got home it was still NE. Light Easterly now here and I have noticed a Sc level convergence line just to the south of here
Nothing noticed locallyon the Templeton Lightning tracker tho'
Well just have to wait and see
By the way today I have given a 2 because of these events
Will let you know on any up-grades, or down-grades as events begin to happen.