03 Stormchaser wrote:Interesting to note light NE breeze this afternoon created some weak instability above chch and the plains this afternoon
I couldn't lodge onto the forum last night for some apparent reason to say that a weak Cb (Cn) formed near Mt.Somers way yesterday afternoon but it glaciated very quickly and nothing really happened.
Yes some weak instabilty happening possibly the best we are going to get for a while by the look of it
NZ Thunderstorm Soc wrote:
Interesting virga on the NW Arch this afternoon. One bit of virga looked like a funnel cloud extending from it
(Wish I had a digital camera again)
JohnGaul
NZTS
Would be impossible as a funnel cloud needs to have rotation.
NZ Thunderstorm Soc wrote:
Interesting virga on the NW Arch this afternoon. One bit of virga looked like a funnel cloud extending from it
(Wish I had a digital camera again)
JohnGaul
NZTS
Would be impossible as a funnel cloud needs to have rotation.
The late ? from Colgate (Tony T would know his name)once recorded lightning in a NW Ach so maybe a rotational piece of virga could of eventuated????
....but, I don't think so as virga form is rather an evidence of dropping precipitation falling from a cloud but evaporating before hitting the ground.
With the lightning down south (I'm not picking anything up sferically) ...anything could happen?
I know the exact bit of Virga you are talking about John. Me and Steven Graham saw it from Templeton around 3:15pm. It did look like a funnel but no, it wasn't. Just a bit of Virga. lol. I should've taken a photo! Oh well.
Yes John, small chance of thunder here in Canterbury tomorrow. Two things are uncertain for me, some models (LAPS, GASP) suggest a Sw flick going up the coast tomorrow in the afternoon (which brings some vorticity to which is what I like!). Which is a good thing for thunderstorms but will it actually come at all and will the high to the west in the Tasman sea ridge in too much and prevent it from happening? And the other is moisture availability before the change. Dew points have been low today due to the NW flow, will it recover to the needed 6 to 8 degree dewpoints needed tomorrow? It doesn't seem like a great chance but here's hoping.
Other factors look to be there, cold pool coming over in the form of an upper trough, also temps should be ok'ish (13 or 14 degrees) which we'll need to get anything.
We had an arch, virga and mammatus today. Great sky. Needed a super wide angle shot of the sky, would have been sweet. All my colleagues kept wondering why I spent most of my time outside today staring straight up
There is no such thing as bad weather, just the wrong clothes.
Interesting suggestion there Aaron, A couple of days ago I would have been more confident about posiblity of thunderstorms, still I do see a chance but very slim in my books!! Lets hope you are right!!
Aaron J Wilkinson wrote:
I took a pic of some of the weak stuff but could'nt see any Cb, might've been too distant for me to see?
Looks excessively boring in Canty...
What's this virga though?
MetService predicting dry weather for the Ak-Waikato regions tomorrow but light showers do look probable with light N or NW winds
Yeah, pretty boring. Virga is like a rain swath that evaporates before it hits the ground I think? Here's a pic:
Explanation from Weatherzone website: Streaks or wisps of precipitation falling from a cloud but evaporating before reaching the ground. In certain cases, shafts of virga may precede a microburst; see dry microburst.
Just to note dewpoints got to 7 degrees today when it went NE which is higher than I thought and provides a bit more promis. Still, will have to wait and see.
I'm not saying it will or will not happen tomorrow, hopefully something does though 03Storm!:D These things are so fickle, it seems to be more likely than other days though.
Dewpoints are actually ok. And temps look ok to for this afternoon. However as I said yesterday the ridge could play too much dominance and not let the SW flick through (which possibly looks like happening). Cold upper air is still there (sort of, it seems to be struggeling a bit more if there is such a thing)
I don't think it's out of the question for thunder as long as the conditions suite, on the 8th of August last year we had some Cb's on the plains with isolated thunderstorms: See here, 8th August
I don't think it's out of the question for thunder as long as the conditions
For winter thunder over Canterbury I would like to see particulaly cold upper air, well below -30C at the 500mb level, the eye of the trough or low crossing the province, and a surface NE to generate some convergence. Daytime heating could assist.
Another scenario could be a wintry squall line coming up the coast. But often the thunder with those is well off the coast over the warmer sea.
Aaron J Wilkinson wrote: Two things are uncertain for me, some models (LAPS, GASP) suggest a Sw flick going up the coast tomorrow in the afternoon (which brings some vorticity to which is what I like!). Which is a good thing for thunderstorms but will it actually come at all and will the high to the west in the Tasman sea ridge in too much and prevent it from happening?
And this looks to of been the case so no storms. Yes John, no umphh! The dewpoints did surprise me I must admit, we got to an 8 degree dewpoint with a temp of 14 which went to 13 when a NE came through. If we did have that southwest flick something could've happened! Oh well, next time whenever that'll be!
