Thunder Watch No2

NZ Thunderstorm Soc · Mon 10/11/2003 22:18

Judging from models and MetService/BlueSkies predictions, I am putting out a Thunder-Watch for Canterbury on Thursday 13th November and also for Sunday 16th November.
Conditions could be ideal for both dates but of course depending on atmosphereic conditions and timing.
Deano and Aaron be aware.

JohnGaul
NZTS

tich · Unread post by **tich** » Tue 11/11/2003 21:18

Judging from models and MetService/BlueSkies predictions, I am putting out a Thunder-Watch for Canterbury on Thursday 13th November and also for Sunday 16th November.

Thursday looks quite likely for scattered thunder and hail, but judging from the models I've seen, Monday seems more likely than Sunday for the 2nd predicted dose. (Monday is also looking wintry with quite a strong cold southerly/southwesterly spreading over NZ)

NZ Thunderstorm Soc · Tue 11/11/2003 22:40

Thursday looks quite likely for scattered thunder and hail, but judging from the models I've seen, Monday seems more likely than Sunday for the 2nd predicted dose. (Monday is also looking wintry with quite a strong cold southerly/southwesterly spreading over NZ)[/quote]
I haven't seen the latest models yet but will do so after I'm off the forum but looks like a later scenario develping which does not favour Ts forecasting ...but will see what happens

JohnGaul
NZTS

tich · Unread post by **tich** » Wed 12/11/2003 15:16

MetService forecast is for isolated showers, possibly with thunder and hail, for Canterbury tonmorrow afternoon. That means there's a small chance that somehere in the district could get the storms, but don't count on it. Should be some interesting cloud buildups, even if they don't amount to much (in the way of thunder and hail).

No sign of the predicted scattered rain for Chch today. Instead the high cloud cleared away about midmorning, and it's been sunny and warm since then, though with a gusty norwester.

Michael · Unread post by **Michael** » Wed 12/11/2003 16:08

Pretty much the same here today -a little warmer as its more WNW rather than SW today but we could get thunder from the front when it goes back to another dirty SWer

NZ Thunderstorm Soc · Wed 12/11/2003 17:36

tich wrote:MetService forecast is for isolated showers, possibly with thunder and hail, for Canterbury tonmorrow afternoon. That means there's a small chance that somehere in the district could get the storms, but don't count on it. Should be some interesting cloud buildups, even if they don't amount to much (in the way of thunder and hail).

I'm still maintaining my thunder-watch for tomorrow for Canterbury at the moment.

JohnGaul
NZTS

NZstorm · Unread post by **NZstorm** » Wed 12/11/2003 19:12

John,
Isolated thunderstorms with hail for Canterbury tomorrow afternoon looks like a fair assessment of the risk. The cb's most likely near the coast where there is moisture and possible convergence.

That front out in the Tasman Sea looks quite weak this evening.
Slight risk of cb's/ts developing on this front before it reaches the NI tomorrow.

Chris Raine · Unread post by **Chris Raine** » Thu 13/11/2003 09:45

We are having showers of hail down here in Invercargill this morning. Hail stones are 5-10 mm in diameter. Temp 4.5 degrees. Reasonable Cb's out there.

tich · Unread post by **tich** » Thu 13/11/2003 10:21

We are having showers of hail down here in Invercargill this morning. Hail stones are 5-10 mm in diameter. Temp 4.5 degrees. Reasonable Cb's out there.

With temperatures like that at sea-level, I'd guess the snow level in the far south is lower than the 700 metres predicted by MetService. Further north, some scattered showers are popping up around Chch, but not yet affecting the central city. Looks a bit more likely for thunderstorm activity this afternoon.

tich · Unread post by **tich** » Thu 13/11/2003 14:15

Now raining (spitting rain but enough to wet the ground) in central Chch; there have been brief spits since late morning. Colourful 1PM Canterbury radar, with patches of red - I wouldn't rule out thunderstorm activity this afternoon, though I haven't noticed any yet. Down to 11C now, with Le Bons Bay station (about 100 metres asl) on only 6.7C at 1PM.

NZ Thunderstorm Soc · Thu 13/11/2003 14:48

Thunder heard in dark cloud to the north of the city around noon but nothing else. Cloud looked to be moving north, so Tony T may get a shower from it.
Apart from that quite overcast and rather cool, 9C here with a moderate southerly breeze. Unfortunately, I think the chance of thunder activity is rather minimal now but will still maintain the thunder-watch for the rest of the day.
Light rain falling here around 1:15pm but not enough to fully wetten the ground.

JohnGaul
NZTS

tich · Unread post by **tich** » Thu 13/11/2003 15:21

Thunder heard in dark cloud to the north of the city around noon but nothing else.

I was speaking to someone at Ferrymead Heritage Park a few minutes ago, and they said they had thunder and brief hail about 2 hours before. (shortly after 1PM)

TonyT · Unread post by **TonyT** » Thu 13/11/2003 15:52

Hail and rain in Rangiora around 12.30pm for about 5 minutes, then a couple of claps of thunder around 1.30pm, one quite close and loud.

NZ Thunderstorm Soc · Thu 13/11/2003 16:52

Whilst getting a haircut this afternoon, the barber said they had a brief hail shower "out of the blue" (mind you they sky was rather grey, but meaning she didn't expect it) around noon over the other side of Sydenham. She heard no thunder tho'
Although the Rakaia radar looks as though there are heavy showers possibly with hail, I'm going to cancel my thunder-watch as the sky looks too settled for any Ts development and the southerly is persistent here.
May have better luck with the next change, possibly Monday at the moment.

JohnGaul
NZTS

NZstorm · Unread post by **NZstorm** » Thu 13/11/2003 18:06

The observed thickness at Invercargill today was 5257. The 500mb temperature -34C. Freezing level around 800m. That is a very cold atmosphere.

Front was mediocre over Auckland this afternoon with just brief heavy rain.

ECWRF suggests a slow moving low over the NI early next week.

Dean. · Unread post by **Dean.** » Thu 13/11/2003 19:10

The front went through when I was at work at 8.30am,some good looking Cb's at the leading edge of the front.Pity it didnt arrive after lunch,might have been a bit more violent.Currently still showery and chilly only 8 degrees.
Cheers.

tich · Unread post by **tich** » Thu 13/11/2003 20:09

The front went through when I was at work at 8.30am,some good looking Cb's at the leading edge of the front.Pity it didnt arrive after lunch,might have been a bit more violent.Currently still showery and chilly only 8 degrees.

There were thunder and hailstorms in parts of mid-Canterbury today. TV1 Weather showed footage of a blanketing of hail at Hinds, about 20km southwest of Ashburton. Still cloudy and cold with the odd shower in Chch.

Dean. · Unread post by **Dean.** » Thu 13/11/2003 21:05

Yeah I did see that report on TV One,pity I was stuck in a middle of a boning room with no windows.........bugger.
Fresh snow on the hills judging by Mt Hutts webcam.
Still showery now only 7 degrees.

NZ Thunderstorm Soc · Thu 13/11/2003 22:32

I still think it was a rather boring day thunderwise despite the newsshots/weather reports and what I observed of the day.
Next thunder-watch is for Monday
I hope Monday prooves more fruitful but it probably won't

JohnGaul
NZTS

tich · Unread post by **tich** » Fri 14/11/2003 10:18

The weather has cleared in Canterbury, but looks like many parts of the North Island could be in for thunder and hail today. Already I've heard (on a National radio traffic report) of hail and snow affecting the Rimutaka Hill Road. Snow? Surely they've mistaken hail for snow. The MetService mountain forecast this morning has the North Island freezing level at 1400 metres, with snow down to about 1000 metres. (it was 1.4C in Waiouru at 7AM) The top of the Rimutaka road is just below 600 metres asl.

Michael · Unread post by **Michael** » Fri 14/11/2003 11:51

Just like a typical British Summer here Lots of rain,windy as and 17 degrees as a high so late in the season

Chris Raine · Unread post by **Chris Raine** » Fri 14/11/2003 12:15

I drove in a significant hailstorm and squall from Clinton to Milton in State Highway one from about 4.30pm to 5.30pm yesterday Again the hail was about 1cm in diameter . On the Old Coach Road summit altitude about 300 meters it was snowing mixed in with bursts of hail.

When I qrrived in Mosgiel now ahead of the squall line which came through at 6pm we had another short hail shower which cleared to cold blue skies.

Thunder · Unread post by **Thunder** » Fri 14/11/2003 13:44

I agree with you John, the day wasn't that great in terms of thunder and lightning as I actually didn't hear or see any (There is a possibilty I heard some thunder but with so much machinery operating near me I'm not sure that it was). Some of the cloud structures did look ok though, in the morning when looking SW or S (something like that) I saw big Cu clouds that looked really punchy (crisp and well defined) and one that had gone to a Cb. Although the clouds looked great I relised that the southerly had come a little to early when I thought it was actually going to arrive in the evening, as Deano said it was a pitty it didn't arrive until after lunch as it could of been a bit more violent (well said). I was out at Wgram again and managed to get some pics that look reasonably ok considering it was my little digi that took them, where I was we only got a tiny we bit of rain (more like a few spits) but I see that the eastern side of Chch got a lot more rain and in New Brighton hail. When looking eastwards from my location you could see the big rain and hail swaths (Is that how you spell it? "Trails" anyway).

Here are some pics from yesterday.

This is the closest thing I saw that looked like a funnel cloud, could it of been? I'm not sure, my experience is limited! Probably not though.

Another shot.

Cu going up into Cb, other clouds high up make the situation darkish looking.

More Cu going into Cb.

Cloud over Chch, looking from Wigram towards Port Hills.

More cloud etc, a bit more sun in this shot.

Dark cloud out over east side of Chch.

And that compiles yesterdays events!

I thought I'd add this shot, it's from a few weeks back and thought it looked cool.

On a different note (well different day anyway), I believe that the 27th of October 2002 storm could well of been a supercell, things that tell me this are:

1) I can remember my freind telling me how he saw the cloud base rotating, I've only just remembered him telling me this. Perhaps his statement might describe a mesocyclone?

2) When looking at John Gauls footage there are certain features that I can see that have hints of supercell, I'll show you some other time John, too long to describe here.

3) Add to the fact there was a tornado:

and golf ball sized hail, I think it could well of been!

Mayby?

Cheers
Aaron Wilkinson

tich · Unread post by **tich** » Fri 14/11/2003 21:23

Already I've heard (on a National radio traffic report) of hail and snow affecting the Rimutaka Hill Road. Snow? Surely they've mistaken hail for snow.

On TV1 Weather, Jim referred to a mixture of hail and sleet settling on the Rimutaka Hill Road. So probably snowing a few 100 metres above the summit of the road. I haven't heard any other reports of hail and thunder in the North Island, but I wouldn't be surprised. The Taupo webcam showed some shower activity to the south - most probably snowing on Mt Ruapehu, knowing the chilly temperatures today in the central North Island.

Tomorrow in Canterbury, a southwest change is forecast by MetService to bring a period of showers. No mention of thunder or hail, and I'm not expecting it (probably no showers at all), but I can't rule it out if the change is preceded by a northeasterly breeze, warm sunshine and arrives in the afternoon.

tich · Unread post by **tich** » Sat 15/11/2003 12:06

Tomorrow in Canterbury, a southwest change is forecast by MetService to bring a period of showers. No mention of thunder or hail, and I'm not expecting it (probably no showers at all), but I can't rule it out if the change is preceded by a northeasterly breeze, warm sunshine and arrives in the afternoon.

We've recetnly had a short period of rain in Chch, accopanied by a southwest wind change, and a rise in the barometer. Was sunny and warm before the rain and is sunny again now, but definitely cooler.