Another deep (Tasman) LOW: Jul 29-Aug 1st

[Vertigo]

another thing i just noticed on the metservice 7 day model is ANOTHER south-bound deep low pressure system hot on the heels of this one, also set to strike us. yikes! this has certainly been an interesting winter!

edit: (ill call this next one the second, and the one i spotted the third) this third system seems to form out of a polar low which makes its way north to the waters NE of queensland, and intensifies once there. when things start forming there, they sure form quickly!

[CHCH Weather Chaser]

Looking at the metservice forecast imagery, there looks to be another one making land fill on Wednesday smashing AUckland with 43+ mm in a 6 hour period. See Below and run it through to Wednesday on the time line.

http://www.metservice.com/default/index ... st_7daytas

[Willoughby]

There, got two threads on each low forecast now.

[Myself]

another thing i just noticed on the metservice 7 day model is ANOTHER south-bound deep low pressure system hot on the heels of this one, also set to strike us. yikes! this has certainly been an interesting winter!

edit: (ill call this next one the second, and the one i spotted the third) this third system seems to form out of a polar low which makes its way north to the waters NE of queensland, and intensifies once there. when things start forming there, they sure form quickly!

A polar low? I don't think so. Pretty rare to see those form in NZ, actually the southern hemisphere as a whole is not a good place for them in general.

[Vertigo]

just going from what i saw in the model run. looks fairly southerly. if not polar, then it was born in the forties.

[Philip Duncan]

This next low next week...not this weekend, next week (lol) could be a major rain bearer for the nations northern and western regions. Definitely worth keeping an eye on, especially those from Waikato to Nelson.

BTW - isn't it weird that we're talking about what is in theory a tropical cyclone (although not technically) slap bang in the middle of winter!? I know it's possible...but still, strange!

Phil.
www.weatherwatch.co.nz

[Myself]

just going from what i saw in the model run. looks fairly southerly. if not polar, then it was born in the forties.

"Polar low" doesn't mean "low from polar regions" though, it's like a very shortlived rapidly intensifying small scale feature- doesn't have the same structure as standard depressions.

[NZstorm]

This low pulls a moist warm sector down across northern NZ Wedneday which will result in thunderstorms. Hopefully this will verify.

[NZstorm]

David wrote

Also the models have taken a complete turn regarding the expected storm mid-week, almost suggesting it won't amount to anything at all now!

I would tend to ignore that run and see whats showing tomorrow. Its a sudden change.

[Willoughby]

^Yes... the ECMWF is still forecasting it very nicely (the thoroughbred).. as is the Canadian Met, BoM's GASP, and UKMO on the 00Z runs.

[NZ Thunderstorm Soc]

Yes, it's looking like a "Drewery" low pressure system scenario developing over us at the moment, well for the next coming week, with more lows moving across us from the NE or west, according to various models

JohnGaul
NZTS

[ricky]

The last GFS run has it back in full force...

[Gary McConnochie]

Sure looks promising for some heavy falls here in Canterbury.

[CHCH Weather Chaser]

Heavy Rain for Canterbury? When? How much and why do you say that?

[Storm Struck]

Yes models have swung back again in comparision with yesterdays, looks like a decent amount of heavy rain for us come Wednesday night/early Thursday and over reasonable duration too.
Its a N-NE fed low so there wont be any cold air being dragged into this one, for example no snow but perhaps at higher elevations.
Cheers
Jason.

[CHCH Weather Chaser]

That will be interesting on already very wet paddocks and grounds in the city. Steady thick drizzle out there now and next few days meant to be rain at times. I see blue skies have 20-50 mm possible on wed and thurs as well! Maybe flooding for us at some stage mid next week

[NZ Thunderstorm Soc]

That will be interesting on already very wet paddocks and grounds in the city. Steady thick drizzle out there now and next few days meant to be rain at times. I see blue skies have 20-50 mm possible on wed and thurs as well! Maybe flooding for us at some stage mid next week

I have created a new topic on this subject, regarding this possibility

JohnGaul
NZTS

[Manukau heads obs]

wow
latest gfs run has this next low as even bigger than this last one
(not as deep, but bigger in size)
will give more rain than the last one, as its slower moving

[David]

Yep looks like a lot of rain coming down with this system. There could be a ridge to the south of the South island which would slow it down. After yesterday we are on 166mm for July so it is looking certain to exceed 200mm as the final total.

Interesting to note that a few of the models are showing another decent low to cross the NI a few days after this next one!

[squid]

models have this next low a very large system and not moving as fast so storng winds/rain look to hang around longer this time the models have this low around the 980 mark with it crossing the middle of the NI if that comes off the winds wil be more NNE over the NI this would mean more rain than thiis time round so i would expect some serious flooding in the NI in the usuall places

[CHCH Weather Chaser]

wow!! The next low is really looking like its moved a lot further south and canterbury is going to cop quite a bit of it to. Yes it does look impressive and much larger and slower moving!! Thick drizzle here in CHCH. over 60mm rain here in last 3 days and with all this to come who knows...lake levels running very high and paddocks are still flooded...... its showing 977hpa now

[Peter]

Looking like a seriously heavy rain event for the North Island overnight Tuesday/Wednesday morning - considering how soggy the soils are already, there will considerable runoff - and I guess another week of the playing pitches being closed!

[David]

See attached...169mm rainfall according to this forecast!
And this is for Auckland - I imagine Coromandel/BOP will receive heaps of rain.

[spike_01]

Looks pretty serious.. My Lady friend lives in Tauranga.. I will let her know as she drives a lot..

[Inny Binny]

50mm in six hours? For gfs to have that forecast, it must be serious, all right...rain is looking pretty widespread over much of the country.