Tasman Low

Willoughby · Unread post by **Willoughby** » Thu 07/10/2004 16:37

Thundery outbreak expected tomorrow (On John's scale, a 4) for Northland to Taranaki including BoP...
We havn't had some thunder lately at all so some would be nice!!

Today it's been cloudy with some rain developing, light winds, 12c

p.s., how on earth do I save images off the web on a bloody mac!!!???

ricky · Unread post by **ricky** » Thu 07/10/2004 17:02

quite a bit of lightning showing up on the metservice map now around northland.. mostly to NE..

spwill · Unread post by **spwill** » Thu 07/10/2004 17:13

Some Downpours into the Auckland area now.

NZstorm · Unread post by **NZstorm** » Thu 07/10/2004 17:35

You bet me to the NZTS convection scale Foggy. I agree, a 4 for tomorrow and 4 for Saturday.

The chances of thunder will rise if there is a period of good surface heating to raise the temperatures which leads to thermal destabilisation.

NZ Thunderstorm Soc · Thu 07/10/2004 18:15

[quote="Aaron J Wilkinson"]That rain radar shows some heavy rain last night at 4am. I didn't notice it or wake up though. Was it really that heavy? This is what I'm affraid of. A big lightning storm will come through at night and I'll sleep through it, everyone will say, "Aaron, did you see that storm last night etc etc", "No" I'll say and everyone will laugh at me.

Anyway.....!!!

quote]

Yes Aaron, it did chuck it down especially around 4am.
Even though the bedroom/front room has a tiled roof, I was awokon by the rain at 4am. I got up, went for a 'Johnny Riddle" and the rain on the roof in the toilet was very loud. I turned the back-yard light on for a look and it was really urinating down. Calm, although I sensed a light easterly with rain spots on our french doors which face to the east.
Anyway, I went back to bed, after observing the rain and not really expecting a flash or anything like that went back to sleep and woke up at 6:30am, and the rain had stopped.
I thought to myself that the rain was a wee bit more than drizzle of which MetService had forecasted earlier for the day

JohnGaul
NZTS

NZ Thunderstorm Soc · Thu 07/10/2004 18:22

Aaron J Wilkinson wrote:
Some interesting clouds outside. I guess it's something to do with a convergence between the ENE and S quater winds. An unstable sky...it would help if the pressure was a bit lower and the dewpoit higher and the general temp a bit higher to, so maybe nothing today??

Yes, interesting clouds after this early morning downpour ( I got 16mm of rain from it. I don't know the period that the 16mm fell as I was mostly asleep at the time)
There was a bit of instability out there but not enough to warrent a warning. It did go back to the NE from about 3pm but not enough factors to even dish out a one on my scale

JohnGaul
NZTS

Manukau heads obs · Thu 07/10/2004 21:01

18mm here today
latest rain radar shows very heavy rain moving south just east of auckland city!

03Stormchaser · Unread post by **03Stormchaser** » Thu 07/10/2004 22:02

Just wondering were the 163 strikes, on stevens lightning site today were??

NZstorm · Unread post by **NZstorm** » Fri 08/10/2004 07:23

On last nights NZWP sounding the Lifted Index was 0.1.
I'm picking max temps around 18C which will yield LI's down to -3.

7.20am, partly cloudy, 13C.

Skywatcher · Unread post by **Skywatcher** » Fri 08/10/2004 08:04

Here's a plot of all strikes from yesterday on a 900km map. Most of them out in the Tasman were between 00:45 and 03:00.

Edit: Looks like it can only thumbnails JPGs

spwill · Unread post by **spwill** » Fri 08/10/2004 09:44

Have one or two early towering Cu but a medium level cloud sheet spreading down on to us from the North will subdue or kill Convection, hope it moves through quickly.

Thunder · Unread post by **Thunder** » Fri 08/10/2004 10:07

By the looks of things no tornadoes of substance today. Not enough turning in the atmosphere. There's always the chance of some FC's I always say though when a convective environment is about so be on the lookout!

Hopefully that cloud sheet moves over Spwill so things get going!

03Stormchaser · Unread post by **03Stormchaser** » Fri 08/10/2004 10:10

Aaron J Wilkinson wrote:By the looks of things no tornadoes of substance today.

So you think there will be small tornadoes!! lol

Thunder · Unread post by **Thunder** » Fri 08/10/2004 10:27

There's always the possibility of a or some FC's!!

spwill · Unread post by **spwill** » Fri 08/10/2004 11:22

Lots of medium level and high cloud moving over us

from an area of showers way out to our NE.
One or two cu about and Cb has formed out to our west but not strong.

Thunder · Unread post by **Thunder** » Fri 08/10/2004 11:51

There looks to of been a storm barel on down into the BOP at some point maybe last night or yesterday. Or was it 3 hours ago?? There was a storm there anyway. The afternoon should prove ok I would think, just hold on!

C-Nimbus · Unread post by **C-Nimbus** » Fri 08/10/2004 14:12

looks like something should happen in Aucks soonish.

This is the 1pm radar and the cells developing just north of auckland central have done so in the last 3 hours.

It feels quite warm outside to and the humidity is increasing while the pressure is dropping at around 0.5 HPa per hour.

The air has that lovely "still" feeling about it at the moment, and hopefully this midday heating will trigger some Cb development.

NZstorm · Unread post by **NZstorm** » Fri 08/10/2004 16:17

Overcast medium level cloud so far has spoiled what could have been an interesting day. Air is unstable to 9000m, there is sufficient moisture, just need a decent lifting mechanism. But no sun at all today.

C-Nimbus · Unread post by **C-Nimbus** » Fri 08/10/2004 16:53

hmmmm, pity really isn't it.

But never mind, looks like the northland contigent will get it

spwill · Unread post by **spwill** » Fri 08/10/2004 16:55

See what happens tomorrow.

Some Thundery rain shown on the Met Service 4pm Radar to the East of Northland is moving this way, so still the slight chance of something interesting.

Thunder · Unread post by **Thunder** » Fri 08/10/2004 17:20

Yes I could see on the midday skew T moisture looked plentiful through most of the atmosphere which is unfortunate as ideally you only want the lower part of the atmosphere (lower 100mb, roughly 1000m) with moisture.

Storms definately formed just offshore along the east coast. Would this be due to the warmer sea temperatures than the lands?

A storm looks to of just finished off with the Taranaki area and is moving offshore. Another storm looks to be rumbling away right now off the east coast of Northland (200km) down to off the east coast of Auckland (100km).

So as spwill says, something could drift your way from off the sea.

If nothing today tomorrow could prove fruitfull as the upper high and mid level cloud would've most likely gone. I hope, we hope....we need some photo's!

NZstorm · Unread post by **NZstorm** » Fri 08/10/2004 17:59

Yes I could see on the midday skew T moisture looked plentiful through most of the atmosphere which is unfortunate as ideally you only want the lower part of the atmosphere (lower 100mb, roughly 1000m) with moisture

Moist under 750mbs(2500m) is ideal. Dry above.

Midlevel moisture there today due to slow moving frontal trough over region.

Storms definately formed just offshore along the east coast. Would this be due to the warmer sea temperatures than the lands?

Yes, its the warmer sea temps that have triggered the maritime storms.
If there had have been surface heating today, they would have been over land as well. I think maritime storms will weaken if they make landfall.

tomorrow could prove fruitfull

Yes, still a chance for tomorrow. We live in hope.

Thunder · Unread post by **Thunder** » Fri 08/10/2004 18:18

Ahh, lower 250mb! I knew I was close.

My knowledge progresses........

Lets hope things do go ok for tomorrow up there, scene as it's the weekend.

NZstorm · Unread post by **NZstorm** » Fri 08/10/2004 18:40

If the moisture is too shallow, the cumulus will dry out before they get to big.

Am Band static sounds like it is not too distant now. That storm in the Hauraki Gulf must be getting closer. Steady rain here now.

Thunder · Unread post by **Thunder** » Fri 08/10/2004 18:42

Some nice action of the east coast of the NI, moving down in big bands. I'd head for Cape Runaway right now if I could (that bit of NZ that sticks out to the NE), or maybe even the lower part of BOP. I'd say they'd be in for a storm or two within the next 2 hours or so.

That static your hearing Steven must be the big band I'm talking about above.