NZ Weather Forum

Peter wrote: ↑Mon 19/04/2021 07:40 I see the Metservice site has gone berserk on the rain outlook for Auckland, with over 100mm of rain tomorrow evening, with 50mm in an hour after midnight Tuesday Will be interesting to see if that verifies, hasn’t been very reliable over the past few rain events.

Well, that was a “bust” from the Auckland reservoirs perspective - about 5-6mm in Auckland Central ... being on tank water for irrigation, I keep a close eye on the MetService rain forecasts, and they haven’t been very reliable lately.

Caught the edge of that rain band a bit better out east yesterday evening, 19mm in total for me. Was a bit surprised it was all gone by 9pm though.

MetService's computer generated 1-hourly forecasts have never been that accurate, which is why they carry this proviso:

The hourly model data shown can differ from the written forecast and icons, which are produced by MetService meteorologists and take into account model data along with many other data sources. If they differ significantly, please use the text forecasts.

Not often you see all 4 of MS's Akld sites taking out the day's 4 top windiest sites…

the Hunua Dams should have got something usefull?

Awhituobs wrote: ↑Wed 21/04/2021 08:19 the Hunua Dams should have got something usefull?

21.5mm at the Mangatangi Reservoir.

I was glad it went East, that one might have been a problem if it hadn't.

150mm in whakatane was recorded ..whew

Another lovely fine, blue dome day with light southerlies this morning turning NE from mid afternoon. Calm this evening.
Today's maximum was 19.2C.

Awhituobs wrote: ↑Wed 21/04/2021 20:24 150mm in whakatane was recorded ..whew

I see Metservice Whakatane got 46mm, good instability numbers with that system
Will keep an eye on tomorrow night.
Cold system for next week looking less impressive.

Hmm, yes at this stage it is looking more like a fairly decent and maybe thundery front then SW for a few hours and the cut-off low idea is gone, but we'll see if that's a trend or just a temporary thing. Possibly got excited by two models agreeing on one run.

Im not having alot of faith in models at the moment. Far to inconsistent and any long range runs seem to constantly back away or delay itself then back away some more.

I know this happens on a regular basis but this year has been far worse so far than any other i can think of.
No point in getting hopes up until the actual day if anything now it seems. And we are in desperate need of some rain. I have not seen parts of he country so dry at this time of the year and hardly any snow on the tops of the mountains, just abit fustrating.

re Whakatane , Met Service did mention re 150mm was was recorded...isolated..thunderstorm and associated surface low
we in Wellington soon
might be a critical SWer
i.e better than a southerly
but means less rain chances for canty

A bit of a thunder chance Canterbury Saturday according to gfs.

NZstorm wrote: ↑Thu 22/04/2021 13:49 A bit of a thunder chance Canterbury Saturday according to gfs.

Hope so. nothing much here since the events over the New Year period.

mikestormchaser wrote: ↑Thu 22/04/2021 09:18 Im not having alot of faith in models at the moment. Far to inconsistent and any long range runs seem to constantly back away or delay itself then back away some more.

Same here, Mike. MS over forecasting thunder storm related activity, with any activity being weak or non-existent,
I blame it on climate change

I definitely understand the frustration behind the models lately, I can't figure out what's changed and why there's so much inconsistency on a daily basis sometimes.

Anyway one day that has stayed consistent is Saturday, it seems we are looking at a convergence set up for afternoon/evening thunderstorms.
Onshore NE through the city to about Rolleston, meeting with a lighter NW inland and an incoming surface SW.
Cold upper air but not too strong dynamics so moderate hail.
Tot,s around 58 so quite high.
One day I would have trust in of any of them going forward into next week so far.

spwill wrote: ↑Thu 22/04/2021 08:12

Awhituobs wrote: ↑Wed 21/04/2021 20:24 150mm in whakatane was recorded ..whew

I see Metservice Whakatane got 46mm, good instability numbers with that system

A central Whakatane PWS (about 7 km SE of the airport) recorded 46mm in just 30 minutes , 60mm in 1 hr, and 163mm in the 12 hrs to 8am yesterday. Another PWS about 7 km further south also recorded 164mm in about 12 hrs.

Another fine blue dome day but some high cloud moving in from late afternoon. 19.4C for today. Light NE.

Nev wrote: ↑Thu 22/04/2021 21:35 A central Whakatane PWS (about 7 km SE of the airport) recorded 46mm in just 30 minutes , 60mm in 1 hr, and 163mm in the 12 hrs to 8am yesterday. Another PWS about 7 km further south also recorded 164mm in about 12 hrs.

I saw the 120mm/hr rainfall rate there at the time and went whoa, doubtful it'd be accurate, but impressive none the less.

NIWA's Whakatane EWS (about 5 km SE of the airport) recorded 109mm in 12 hrs, including 40mm in the hour to 3am.

mikestormchaser wrote: ↑Thu 22/04/2021 09:18 Im not having alot of faith in models at the moment. Far to inconsistent and any long range runs seem to constantly back away or delay itself then back away some more. ...

^ What I call the "jam tomorrow" forecasts

Kind of a nor'west arch at the moment with heavy high overcast here; 15°C; no wind to speak of.

I still think actually tomorrow "sat" looks like the most exciting of the days. As mentioned earlier in the week, and i still see a chance of thunderstorms/ hail north otago up eastern Canterbury plains afternoon/ evening.
Next week is still going to be cold but nowhere near the moisture plotted out unless it flops right back around again

Mod rain here now, some distant lightning observed earlier.

Non event here, couple brief showers earlier and patchy rain tonight. 1.5mm and looks to be clearing soon.

NW Arch for much of the day with hardly any wind.
!7,7C recorded today with the high cloud cover. Moving off from mid afternoon.
Clearing away this evening.