Subtropical low NI 15-17 Feb

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Cyclone Tracy
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Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Might as well get this thread underway. As always the finer detail is still being ironed out but we definitely have the potential for one of the wettest systems in a long time over several areas of the NI.
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Re: Subtropical low NI 15-17 Feb

Unread post by Awhituobs »

NIWA are now talking about an atmospheric river developing
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Re: Subtropical low NI 15-17 Feb

Unread post by David »

Totals for here are now 80-90mm on GFS and EC, while Icon showing 140mm.
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Re: Subtropical low NI 15-17 Feb

Unread post by Blowy »

53mm (icon)
showing for Napier, we need that, and some.
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Re: Subtropical low NI 15-17 Feb

Unread post by Awhituobs »

Met service just put out heavy rain warning for Northland and Coro
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Significant moisture pluming in the mid levels now above multiple surface convergence zones north of the NI. As seen in previous events in the SI across the last 2 years, models have grossly underestimated rainfall totals in these types of set ups. This looks like a water bomb to me and I wouldn't be surprised to see some some gauges getting 300mm+ this week. It's all about where the low stalls to who gets bombed.
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Several Northland gauges well over 100mm overnight as of 7am. 141mm at Touwai just north of the Bay of Islands.
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Re: Subtropical low NI 15-17 Feb

Unread post by David »

11mm here overnight, has eased right off already
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

9mm here so far. The east to north east convergence looks like it arrives late morning to early afternoon for Auckland.
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Wind moving to more ENE to easterly locally. Matakana now up to 70mm on the convergence line, Great Barrier Island has a gauge on 64mm.
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Re: Subtropical low NI 15-17 Feb

Unread post by David »

GFS had us on 35-40mm by now so falling a bit short there. Hoping we can get 50mm out of this system :)
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Re: Subtropical low NI 15-17 Feb

Unread post by Peter »

MetService rain outlook has dialed back rainfall considerably since this morning - current radar not looking very impressive ...
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Re: Subtropical low NI 15-17 Feb

Unread post by Happy Feet »

We have had over 100mm near Kaikohe since yesterday and its still a mix of light and heavy showers with low cloud and mist in all directions.
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Re: Subtropical low NI 15-17 Feb

Unread post by Awhituobs »

21mm here so far
happy with that :)
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Re: Subtropical low NI 15-17 Feb

Unread post by David »

21mm here also. I see the Metservice forecast beyond this afternoon is just showers now as opposed to the 2 full days of rain models were suggesting until very recently. A shame, but can't complain too much about 20+mm in Feb!
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

30mm here so far. Not bad for round 1. Next round later tonight with the low wrap around.
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Plenty of water running off the Coromandel ranges at the moment. Most models on the 12z run are already around 100mm out for this location :smile:
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Re: Subtropical low NI 15-17 Feb

Unread post by Awhituobs »

we now at 26mm and more to come looking at the radar
would be good to get above 30mm, becomes more usefull

models are hinting at another sub tropical low in the tasman from the 24th
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Higher resolution Access G 18z drops the wrap around squeeze zone more south from the 12z run around Auckland early tomorrow morning.

Current temp 21.7c , DP 20.6c
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Plenty of mid level juice wrapping in from the SW quadrant of the low.
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Re: Subtropical low NI 15-17 Feb

Unread post by Blowy »

Heavy rain warning for us now . Bugga all so far today ... 1mm in Havelock North
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Re: Subtropical low NI 15-17 Feb

Unread post by NZstorm »

Some tropical air over Auckland now with temp 22C, dewpoint 22C, drizzly rain.
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Re: Subtropical low NI 15-17 Feb

Unread post by spwill »

Metservice Manakau with 21.8C, humidity 98%. A general dewpoint across the Auckland region of 21C.
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Re: Subtropical low NI 15-17 Feb

Unread post by Cyclone Tracy »

Castle Rock in the Coromandel ranges now sitting on 205mm for today. Low's circulation now appearing on the 300km MS radar on loop in the Tasman, inching SE towards Auckland.
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Re: Subtropical low NI 15-17 Feb

Unread post by Awhituobs »

does look like we will get more rain with the low crossing.
great. 30mm here so far :)
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