Possibility for Thunderstorms Mid August

[Tornado Tim]

This is only a forecast at this stage (So don't take it seriously yet) but it seems to have remained in my forecast for quite a while, which means its not tending to flip flop on whats coming up.
Days of interest at this stage are the 15-16th August.
GFS has some amount of CAPE around the NI focusing on the northern part of the island.
TT (total totals) index is hanging around the late 50's, (just take heed of the pitfalls with this index) The only reason i am mentioning it is because it is matching up with CAPE.
LI is forecast to be around -1.7 the max around here anyway but possibly more than that but of this will change.
Here is a Skew-T and forecast Graph and GFS Chart so take from it what u want.
I say again, only a forecast (for now) that we can discuss.

[NZstorm]

Yes, certainly looks like some cold upper air/upper trough crossing the North Island over the weekend (Saturday night/Sunday). I'm not looking at the numbers too closely yet as the gfs fluctuates a bit.

[spwill]

I'm hoping El Nino will give us less Anticyclonic SouthWesterlies and more Low preasure NorthWesterlies this Spring, we are due for an unstable spring.

[Manukau heads obs]

sometimes though that is what El Nino does give us ( Anticyclonic SouthWesterlies )
but maybe more during December if anything (especialy if the sea temperatures are below normal at that time I suspect)

[Tornado Tim]

Latest Skew-T, Looks rather good.

[Michael]

We get more in early summer than we get in winter these days.

sometimes though that is what El Nino does give us ( Anticyclonic SouthWesterlies )
but maybe more during December if anything (especialy if the sea temperatures are below normal at that time I suspect)

[NZstorm]

Latest Skew-T, Looks rather good.

Which location is that forecast skew-t for Tornado Tim? I'm guessing Auckland.

[Tornado Tim]

Its for Matangi, I get them personally done for my Location using a atmospheric modeling system and merging my weather data with it.
This URL is where they get automatically get uploaded to:
http://wx-matangi.dyndns.org/Matangi_We ... ecast.html

[NZstorm]

Looks like the above mentioned cold upper trough comes through later Sunday. But it doesn't look overly strong atm.

The system coming down across the north tomorrow will have a low thunderstorm risk with it. (Northland/Auckland). GFS consistently plots low instability with it.

[Tornado Tim]

Yea thunderstorm risk has been reduced, as usual

[NZstorm]

Yea thunderstorm risk has been reduced, as usual

Roll on October when the surface heating can crank up convection chances.

[NZstorm]

Copy of last nights Auckland sounding here showing a sliver of instability hence the cb's last night, CAPE 275j/kg. Evidently not enough CAPE/Lift to turn them thundery. Anyway I think a mix of daytime warming/wind change convergence will likely throw up more showers today but I am doubting there will be anything thundery.

[NZstorm]

I see there is some weak cb/tcu about now.

[Tornado Tim]

My forecast is picking up on a possibility of storms just before and after midnight though after midnight is looking less likely .
Here are some Skew-Ts for reference.
Just incase you dont know how to read them: http://wx-matangi.dyndns.org/Matangi_We ... _Help.html

[David]

I see the Massey (West Auck) weather station was recording a heavy downpour at it's 1.30pm update...
(http://weather-west.net/our_weather.htm)

Has just become sunny here and a pleasant temperature of 17.7°C

[jamie]

sure is tropical out there. nice low hanging clouds indicating a close dew point to the temp. If it was mid summer would this be a stinking hot muggy day?

[Vertigo]

definitely more muggy than usual.