Complex low pressure system & cold outbreak 3rd-8th August

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Bradley
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Re: General August Weather

Unread post by Bradley »

Really liking the look of EC's latest run for heavy snow above 300m for next Thursday for Canterbury, interestingly enough even the Metservice forecast is backing it up at this very early stage
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NZstorm
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Re: General August Weather

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Bradley wrote:Really liking the look of EC's latest run for heavy snow above 300m for next Thursday for Canterbury, interestingly enough even the Metservice forecast is backing it up at this very early stage
Looking like a warm advective snow set up. Early days to focus on numbers but typically these set ups drop a lot of snow.
Bradley
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Re: General August Weather

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NZstorm wrote:
Bradley wrote:Really liking the look of EC's latest run for heavy snow above 300m for next Thursday for Canterbury, interestingly enough even the Metservice forecast is backing it up at this very early stage
Looking like a warm advective snow set up. Early days to focus on numbers but typically these set ups drop a lot of snow.
Every promising low level snow event has completely fizzled out this winter so far so I'm not even getting slightly excited by it yet, that cold air on Thursday is so marginal sliding too far East all it will take would be it to move 100km east and it's all over!
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Re: General August Weather

Unread post by spwill »

A slow moving low system so prolonged precipitation possible somewhere, something to watch.
Bradley
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Re: General August Weather

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spwill wrote:A slow moving low system so prolonged precipitation possible somewhere, something to watch.
Latest run of EC has gone berserk with 300mm for places like Kaikoura, 200mm for the foothills in mid Canterbury and nearly 100mm for Christchurch though it has lifted the snow level by 100-200m so 400-500m would be the snowline at the moment...
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Re: General August Weather

Unread post by spwill »

GFS is much slower to bring the low onto NZ but we are looking quite far out so just something to watch at the moment.
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Re: General August Weather

Unread post by treetop »

latest runs has the low moving backwards towards Australia ??? May bring very cold air to the sth of the S Is now but looks moisture starved.
ttttttttttt
Bradley
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Re: General August Weather

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Tony going all out for the ski fields this week:

http://www.stuff.co.nz/the-press/news/8 ... canterbury
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Re: General August Weather

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Bring it on...some onshore weather would be nice after all the Northwest/west/southwest weather this year.Canterbury has been the most sheltered area of NZ q-
mikestormchaser
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Re: General August Weather

Unread post by mikestormchaser »

Something is interesting in the models I see today. I see a potential snow maker system end of week. "Warm advective" hinting some very heavy precipitation, 850mb Temps also hinting very cold temperatures a recipe for something interesting!
Mike
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Bradley
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Re: General August Weather

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What model is that Mike? EC has the system clearing out by Saturday morning
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Re: General August Weather

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Bradley wrote:What model is that Mike? EC has the system clearing out by Saturday morning
This mornings gfs run had it going from Thursday right through the weekend with some pretty cold 850mb temps hinting at quite the decent advective event, haven't checked this evenings run though so not sure if it's still looking good
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mikestormchaser
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Re: General August Weather

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Bradley wrote:What model is that Mike? EC has the system clearing out by Saturday morning
BSCH gfs Bradley. Definitely hinting something could be brewing. More Thursday into fri as Matt says. Some very cold low layer Temps at 925mb and 850. One problem could be a SE wind flow..Witch can warm up the air for costal Canterbury "ie" Christchurch and cause air to freeze inland, so at this stage id say more an inland event but ya never know! There is some heavy precipitation around this time. One to watch!
Mike
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Bradley
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Re: General August Weather

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mikestormchaser wrote:
Bradley wrote:What model is that Mike? EC has the system clearing out by Saturday morning
BSCH gfs Bradley. Definitely hinting something could be brewing. More Thursday into fri as Matt says. Some very cold low layer Temps at 925mb and 850. One problem could be a SE wind flow..Witch can warm up the air for costal Canterbury "ie" Christchurch and cause air to freeze inland, so at this stage id say more an inland event but ya never know! There is some heavy precipitation around this time. One to watch!
Latest 06 run of GFS is looking mighty impressive too Mike, let's hope it holds!!
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Bradley
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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I see Metservice are as uncertain as the rest of us at this point about the potential snow level and are hedging their bets with a generic 'heavy snow to low levels' forecast for Thursday/Friday!

http://metservice.com/warnings/severe-weather-outlook
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Re: Complex low pressure system & cold outbreak 3rd-8th August

Unread post by matttbs »

Looking quite promising still, gfs has been pretty consistent now for a couple days
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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Metservice have 300m in there Rural forecasts Bradley _b
Bradley
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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melja wrote:Metservice have 300m in there Rural forecasts Bradley _b
Yep just saw that, I wonder why they couldn't be more specific on their outlook then?
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Re: Complex low pressure system & cold outbreak 3rd-8th August

Unread post by mikestormchaser »

Not going to be warm Friday. I see a max temp for Christchurch of about 6-7C
Mike
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Re: Complex low pressure system & cold outbreak 3rd-8th August

Unread post by SnwAddct »

Looks like Central NI is now included in this weeks weather, not quite as moisture rich as Canterbury but plenty of moisture around and a freezing level of around 500m at times.. Great to see all these winter systems unfolding =D>
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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Latest run of EC has halved the moisture levels for Canterbury but has dropped the snowline down to about 100m, certainly going to be very cold. Looks like it has another cold blast on Monday as well, this time with snow to sea level but very little moisture, only 2-5mm
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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The winter event kicks off as warm advective snow inland South Island Wednesday with heavy falls typical of this type of scenario.

Gfs shows a decent polar outbreak by Friday with snow showers lowering to sea level in the South Island.
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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Hanmer Springs looks to be in the firing line with 60cm + over the 4 days
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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Metservice now on board with a severe weather watch issued for Wednesday til the weekend. There will be some itchy farmers about
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Bradley
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Re: Complex low pressure system & cold outbreak 3rd-8th August

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This mornings run of EC has halved the moisture levels again for coastal Canterbury and most inland areas too, this looks to be one of those systems which is winding back the closer we get to the event which I guess is pretty consistent with every promising weather system this winter to date :rolleyes:
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