General May Weather

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tornado
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General May Weather

Unread post by tornado »

what do you all reckon about the low pressure system that is coming in on the first weekend of this new month coming up? i reckon it could contain a few thunderstorms for us north islanders and some decent rain maybe.
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Re: General May Weather

Unread post by NZstorm »

Both gfs and Eu showing some heavy convective precip with that front at the weekend over the NI. Often these set ups end up being hit and miss with 50mm in one spot but 5 mm in another.
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Re: General May Weather

Unread post by NZstorm »

Auckland regions rainfall from the moist front late weekend according to latest EU. Looks like thundery rain in the Tasman Sea breaks up but then reforms to the east. A rain shadow affect for Auckland. But its just model output so change likely.
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Re: General May Weather

Unread post by tornado »

yes it will change. still a few days away. i just hope for a good storm.
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Re: General May Weather

Unread post by David »

Even 20mm would be excellent these days
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Re: General May Weather

Unread post by tornado »

David wrote: Wed 29/04/2020 08:02 Even 20mm would be excellent these days
i agree.
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Re: General May Weather

Unread post by Chris W »

Just for fun here’s the GFS ensemble spaghetti plot showing 500mb heights for Tuesday, a model with no data scratching around and also being fair that’s nearly a week out!
C072D9A3-E859-4311-8183-DBEDC2411AD4.jpeg
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Re: General May Weather

Unread post by spwill »

The forecast high for Sydney tomorrow is 16C, Canberra 7C, that cold air reaching NZ next week.
Thunder chances here early next week.
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Re: General May Weather

Unread post by Cyclone Tracy »

The UKMet is starting to get excited for the upper NI on Sunday into Monday around that warm front. Locally the average across all models is suggesting 40 to 50mm. With the ridging that has continued for the last 16 months, it's another believe it when I see it scenario.
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Re: General May Weather

Unread post by Razor »

Looking at models it is hard to pin down what might eventuate for us in Canterbury over the weekend or into next week. Could be a fizzer I think for us, West Coast to get an autumnal hammering though
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Re: General May Weather

Unread post by NZstorm »

The UKmet has been putting out some odd runs lately for rainfall.

The EU looks more reasonable with hit and miss convection rainfall from the front Sunday. East Auckland tends to do best out of this given the surface flow with the front will be northerly.

Some cold air thunder on Monday down the west of the North Island but looks like Taranaki gets the bulk of that at this stage.
Last edited by NZstorm on Fri 01/05/2020 06:55, edited 1 time in total.
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Re: General May Weather

Unread post by Cyclone Tracy »

GFS and others are projecting an upper low cutting off near NZ from a rogue polar streamer mid next week, lowering the tropopause to around 8000m near New Caledonia. Key ingredient for the development of a tropical / subtropical depression north of NZ.
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Re: General May Weather

Unread post by David »

Current GFS has around 60mm modelled here Sunday-early Monday then an additional 80mm mid-late next week. Of course this will keep varying in the models but it's exciting to see such numbers
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Re: General May Weather

Unread post by Chris W »

Cyclone Tracy wrote: Fri 01/05/2020 06:52 GFS and others are projecting an upper low cutting off near NZ from a rogue polar streamer mid next week, lowering the tropopause to around 8000m near New Caledonia. Key ingredient for the development of a tropical / subtropical depression north of NZ.
Seems likely to hang around for 2-3 days, could be the system you guys have been waiting for up there. Sustained rain and less heavy than what the GFS op is modelling for Sunday. Certainly hope so.
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Re: General May Weather

Unread post by Orion »

Observed some mares' tail clouds this morning.
Another mild day, still 19.2°C at the moment.
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Re: General May Weather

Unread post by tornado »

models were showing a big high after this tasmin front and low but now its shows a subtropical low coming in. will flip flop and i bet that sub low may end up staying to the east like all of the lows from the north did.


looking foward for some rain and at least one decent thunderstorm here.
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Re: General May Weather

Unread post by NZ Thunderstorm Soc »

tornado wrote: Fri 01/05/2020 20:30


looking foward for some rain and at least one decent thunderstorm here.
Normally Auckland does hog in thunderstorms from this time of year, so you should be lucky.
Another fine day here with some high cloud. Today's maximum being 21C.
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Re: General May Weather

Unread post by NZstorm »

Subtropical moisture tomorrow with dewpoint 17C for Auckland! Certainly good conditions for possible heavy convective rain. 500mb temperature looking a bit too warm though for Auckland to get lightning tomorrow.

GFS likes Westland for a possible tornado tomorrow with colder upper air coming into that area and low level wind shear.
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Re: General May Weather

Unread post by Awhituobs »

the models are getting excited about the sub tropical low from the north
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Re: General May Weather

Unread post by Orion »

It's gone quite dull here with thick high overcast and a north-west arch;
brought washing indoors as the wind rose sharply, felt a few drops of rain.
17.6°C at the moment.
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Re: General May Weather

Unread post by Chris W »

Isolated thunder potential for Chch on Tuesday, or just hail? Cloud cover but -30C air enhancing chain showers. Looks like we will get a little rain this week, if not that much.

GFS starting to take that subtropical low further east as a ridge delays it’s approach, EC further west. Could be a cold lash in its tail for the eastern South Island.
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Re: General May Weather

Unread post by David »

Showers have arrived already, wasn't really expecting anything until later today...
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Re: General May Weather

Unread post by NZ Thunderstorm Soc »

Nice and warm here this evening, currently sitting on 20.5C, the warmest so far today.
Interesting that it is warmer outside than inside at the moment. :rolleyes: :crazy:
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Re: General May Weather

Unread post by Awhituobs »

GFS flagged away next weekends low from north
Euro going all out
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Re: General May Weather

Unread post by David »

Hmm don't see much on EC currently. Low passing to the east.
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