Depressing Depressions!
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For today's weather discussion head to: New Zealand Weather & Climate
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For today's weather discussion head to: New Zealand Weather & Climate
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I can usually tell when we're in a westerly rather than a northwesterly flow - the clouds are different. In a northwesterly, there is usually high northwest arch style cloud, while in a westerly (like today) there is scattered cumulus. I guess that's an indication we're in a colder airmass, even though it might still be mild in Chch.
- NZstorm
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Alot of lightning about today Brian. 419 strikes is impressive. That would be composed of both CG and CC.
And I saw the cb boilup over North Auckland on the 2pm satellite. I notice the cb activity has even got into the BOP today.
Over the last two days the upper air over Auckland has progressively become more unstable(off the surface), while surface dewpoint temperatures have stayed relatively high(around 15C). A weak frontal zone over the region has provided the extra instability and forcing to trigger the convection. With all the low cloud about I cannot see the cb buildups. Pity.
I am hoping this ts activity is still about tonight. Still crackling on the am band.
And I saw the cb boilup over North Auckland on the 2pm satellite. I notice the cb activity has even got into the BOP today.
Over the last two days the upper air over Auckland has progressively become more unstable(off the surface), while surface dewpoint temperatures have stayed relatively high(around 15C). A weak frontal zone over the region has provided the extra instability and forcing to trigger the convection. With all the low cloud about I cannot see the cb buildups. Pity.
I am hoping this ts activity is still about tonight. Still crackling on the am band.
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- NZstorm
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Looks to be some cb's off the coast of Banks P as you suggest Aaron.
But given the dewpiont in Christchurch is currently minus1C, I don't see them coming to much. Must be a bit of an easterly shift off the coast.
I like the cumulus photo.
Cb's have cleared Auckland. I expect to see more thundery weather with the front tomorrow. Ingredients are there for quite an active front.
But given the dewpiont in Christchurch is currently minus1C, I don't see them coming to much. Must be a bit of an easterly shift off the coast.
I like the cumulus photo.
Cb's have cleared Auckland. I expect to see more thundery weather with the front tomorrow. Ingredients are there for quite an active front.
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Yes, you are right Steven. I saw those clouds too and wasn't interested in them. Westerly blowing and a low dew-point.
I think tomorrow will also be disappointing here in ChCh, just a bit of drizzle now as the barometer is rising now with higher air pressure coming in to cradle the low moving onto central NZ.
The weather event will occur much north of ChCh
JohnGaul
NZTS
I think tomorrow will also be disappointing here in ChCh, just a bit of drizzle now as the barometer is rising now with higher air pressure coming in to cradle the low moving onto central NZ.
The weather event will occur much north of ChCh
JohnGaul
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Some distant sferics on the AM band late tonight. Not continuous but could be from that bright blob way out to the east of Auckland on the 9pm satpic.
Nothing much here at the moment to herald the arrival of the cold SE deluge and Depressing Depression scenario that mooted the posting of this topic. Light Sw. I notice the 9pm Met Service map had a trough line over south Canterbury but there was nothing on the 9pm Rakaia radar.
JohnGaul
NZTS
Nothing much here at the moment to herald the arrival of the cold SE deluge and Depressing Depression scenario that mooted the posting of this topic. Light Sw. I notice the 9pm Met Service map had a trough line over south Canterbury but there was nothing on the 9pm Rakaia radar.
JohnGaul
NZTS
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Deano, there is potential for a heavy snowfall to low levels in Canterbury later today. Met Service say 500m but I suspect the snow level will be well below that. But it all depends on how much of the 'bitterly cold air' over southern NZ advects northward into Canterbury and how much of that warm advective rain to the north comes south. A situation worth watching closely.
- TonyT
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We have been predicting snow to 3-400m in inland South Canty since about Thursday and I still feel that is likely. Probably 5-600m further north. I also feel totals will be quite high in North Canterbury, perhaps 50-100mm rain, 50-70cm snow above 700m, and 20-50mm in Mid and South Canty, perhaps 30-40cm snow. Falls on Banks Peninsula and the Kaikoura Coast could be even heavier. Also, look for serious gales around dawn Monday, especially on the Peniunsula and Kaikoura, followed by a period of heavy damaging swells along the coast.
- TonyT
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Head out Tekapo way Dean, but dont get stuck!
Raining steadily in Amberley since 6am, quite hard now but not yet at the point I would call it heavy. Easterly breeze 15-20 knots, 7 degrees.
This is going to be a major weather system for many parts of the country methinks, and it may be the wind speeds which are the biggest problem rather than the rain.
Raining steadily in Amberley since 6am, quite hard now but not yet at the point I would call it heavy. Easterly breeze 15-20 knots, 7 degrees.
This is going to be a major weather system for many parts of the country methinks, and it may be the wind speeds which are the biggest problem rather than the rain.
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I think we should remember this is a southeasterly rather than a southerly flow, and probably a warm advection rain/snow event. The latest MetService severe warning warning is for heavy rain to affect areas north of the Waimakiriri River and the Kaikoura Coast. The foothills tend to be more exposed to such airstreams, plus snow should fall to lower levels. Banks Peninsula is more affected by direct southerly flows, so I doubt rainfall totals will be as nearly as high there, plus snow levels should be higher. Chch gets a bit of a rainshadow from BP, so should get quite a lot less rain.
So my guess (I might be wrong) is that snow will fall to low levels inland, with some heavy accumulations, and heavy rain will affect the Kaikoura Coast and North Canterbury. (hill country north of Amberley and foothills north of the Waimakiriri) Watch out for possible snow to low levels in Otago as well - Dunedin was only 0.5C at 6AM.
So my guess (I might be wrong) is that snow will fall to low levels inland, with some heavy accumulations, and heavy rain will affect the Kaikoura Coast and North Canterbury. (hill country north of Amberley and foothills north of the Waimakiriri) Watch out for possible snow to low levels in Otago as well - Dunedin was only 0.5C at 6AM.
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- TonyT
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