General July Weather

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CHCH Weather Chaser
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Re: General July Weather

Unread post by CHCH Weather Chaser »

5.5mm of drizzle here overnight. Stopped for now.
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Re: General July Weather

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Only a trickle of lightning coming off that front this morn. Upper will cool off further on top of the front during the day so may see an upswing in lightning activity. Tomorrow looks unstable over the north with isolated ts/hail, most likely over Northland.
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Re: General July Weather

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Tornado Tim wrote:
Dale Small wrote:Unreal David.. those are keepers!
doesnt need to be the NH Tim
You mean Nzstorm?

The IR Sat images look quite interesting this evening...
Yes, I did, realised the mistake well after the edit time had elapsed.. serves me right for trying to pack the boys off to their aunty's & posting here at the same time :x
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Re: General July Weather

Unread post by spwill »

Some heavy rain around Auckland last couple of hrs, current 12C dewpoints feel warm after recent cold spell. Thunderstorms have been occuring off shore east of Northland
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Re: General July Weather

Unread post by Michael »

Steady rain here too,can see on the satellite the curve of thunderstorms just of the top of northland plus the jetstream off australia easily feeding into the low.
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Re: General July Weather

Unread post by CHCH Weather Chaser »

Nothing to report in terms of precipitation today. 6mm overnight but since then nothing. Looked as if the band from the north was closing in but 5pm radar shows it has completely discintigrated.
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Re: General July Weather

Unread post by dan »

Surprisingly heavy and squally rain here.
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Re: General July Weather

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Was interesting seeing the low go past on the graphs. After the pressure bottomed out the wind changed direction and eased, temperature dropped etc...
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Re: General July Weather

Unread post by Storm Struck »

CHCH Weather Chaser wrote:Nothing to report in terms of precipitation today. 6mm overnight but since then nothing. Looked as if the band from the north was closing in but 5pm radar shows it has completely discintigrated.
Why does that not surprise me Christchurch had Drizzle this morning, dry as a bone north of christchurch havnt had any precipitation yet.
I would say patchy light rain from sometime tonight through to tomorrow afternoon.
Canterbury, home of good rugby and severe storms
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Re: General July Weather

Unread post by CHCH Weather Chaser »

Heavy drizzle has returned tonight. Lats half hour. Had the wipers on full.
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Re: General July Weather

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No rain in Barrington - where were you CHCH W/C ??

:-o :-o
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Re: General July Weather

Unread post by CHCH Weather Chaser »

burgla wrote:No rain in Barrington - where were you CHCH W/C ??

:-o :-o
Driving between hoon hay and halswell. Back home in Halswell now and steady drizzle out there still.
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Re: General July Weather

Unread post by 03Stormchaser »

CHCH Weather Chaser wrote:
burgla wrote:No rain in Barrington - where were you CHCH W/C ??

:-o :-o
Driving between hoon hay and halswell. Back home in Halswell now and steady drizzle out there still.
In Bryndwr been pretty steady here for a couple hours now.
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Re: General July Weather

Unread post by NZstorm »

Unstable air over northern regions today, if it were October, there would be afternoon blow ups. I hope we are still getting these northern low pressure systems later in spring. A fine morning with 9C.
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Re: General July Weather

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This cb has just popped up out to the SW of Auckland.
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Re: General July Weather

Unread post by CHCH Weather Chaser »

Drizzle falling here still this morning. The radar shows nothing at all so the cloud must be below the beam. Another 7mm overnight taking the total to 13mm. Interesting GFS output for Canterbury area from Tuesday afternoon through to Friday this morning. Something to watch.
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Re: General July Weather

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good view of that Cb from here NZstorm
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Re: General July Weather

Unread post by burgla »

@ CHCH W/C & 03Stormchaser - first rain at Barrington( from logfiles) last nite was at 2113. Went outside to check before posting last post, & def no rain then at 2040 Friday nite !! - must have a desert island round here !!!

:lol: :lol:
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Re: General July Weather

Unread post by Paul Mallinson »

As NZstorm mentions above, unstable air moves over the north this afternoon with a cold pool of about -27C at 500 hPa moving over Northland and northern Auckland this afternoon. Soundings are very unstable off the surface but the problem will be getting enough of a trigger along with sufficient boundary layer moisture over the land. The instability is moving over during the afternoon heating so I thought it was worth a moderate risk for Northland.
Cloud top temps on that cell to the sw of Auckland are about -47C which puts it right up to the tropopause (witness the anvil in NZstorms picture) - about 29,000 ft but currently no lightning in them. Radar shows that the strong echoes in these cells don't reach very high and so bouyancy up through the main parts of these cells is modest - which explains why there is no lightning.

Will be interesting to see what eventuates.

Paul
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Re: General July Weather

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Thanks for your thoughts Paul. I really enjoying reading what you guys are thinking. Im sure most of us appreciate you putting your thoughts on here.
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Re: General July Weather

Unread post by Paul Mallinson »

Well, if this had still been in summer we would have big action all over the upper North Island. There has been a recent lightning strike just west of the Kaipara Harbour. Temperature and dew points over Northland are running 16/12 to 17/13 and the lifted Index varies from -3 to -6.5! And yet only only a few modest showers over the land with the big stuff over the sea. Just shows you what the summer heating/forcing does. Instead this is over the sea in the form of warm sfc temps with higher dew points there.

Paul
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Re: General July Weather

Unread post by Tornado Tim »

Paul Mallinson wrote:Well, if this had still been in summer we would have big action all over the upper North Island. There has been a recent lightning strike just west of the Kaipara Harbour. Temperature and dew points over Northland are running 16/12 to 17/13 and the lifted Index varies from -3 to -6.5! And yet only only a few modest showers over the land with the big stuff over the sea. Just shows you what the summer heating/forcing does. Instead this is over the sea in the form of warm sfc temps with higher dew points there.

Paul
16.6°C with a Dp of 13.0°C here hopefully some lightning can get going :D
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Re: General July Weather

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Still getting those cbs popping up but yes, July sunshine and a lack of a convergence boundary prevent the instability being capitalised on fully.

I would use a dewpoint of 10C for lifting the parcel today, that'll give a fair assessment of the instability that there.
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Re: General July Weather

Unread post by Vertigo »

Just had a hail shower pass over birkenhead.. first one for the year (for me)! lol.
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Re: General July Weather

Unread post by spwill »

Warmed to 17Ctoday but a lot of old Cb showers around now and 11C.
photo, Cb west of Auckland
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