General December Weather

[NZ Thunderstorm Soc]

Horrah! The sun came out today after 7 days of claggy overcast conditions and yes, it became warm with today's maximum being 28.6C.
Scattered cloud around but nothing threatening. Light winds from the SE of the sea breeze type.
MS forecast for Timaru completely rubbish for today but nevermind.

[spwill]

Otago and South Canterbury look the place for a thunderstorm tomorrow afternoon/evening. A cold trough over the area.

[mikestormchaser]

Otago and South Canterbury look the place for a thunderstorm tomorrow afternoon/evening. A cold trough over the area.

Yes upper cold trough spreads north over south island tomorrow. Eastern SI look set to get thunderstorms and hail. Reaching chch possible at night. Good shear tomorrow aswel

Will be free to chase.

[JP.]

Warm & low humidity start to the day for Christchurch city. 28c at 10:30 am with DP of only 10.6c.

Great morning to be out & about in the sunshine.

[darcyplumb]

Opposite here in Ashburton. 22 degrees C with 75% humidity. Feels much warmer than it is. Gentle easterly.

[darcyplumb]

Big towers going up inland but they’re going to be cut off by John’s favourite claggggggg.

[Storm Struck]

Interesting you have the easterly down there in Ashburton, it's a strong gusty Westerly here in Christchurch after being SW earlier.
Only dropped to 21C overnight, currently just pipped 28C here now.
On the current radar it's obvious there is a SW change down towards Ashburton, going by the windy app it's forecast to not come too much further north. So will probably be some local convergence down there today, unfortunately no surface moisture though.

The MS thunderstorm outlook was what I was thinking for tomorrow, certainly a chance for a severe cell or two.
Around mid afternoon we will probably see a few isolated showers ahead of the cold upper air, these could be heavy with a smaller risk of thunder on the first southerly.
It's the second wave at night which has the high risk.
Upper air is actually a tad colder now on -28c, you certainly would be pushed to see anything colder than that for this time of the year.
Natures own new years light show

[darcyplumb]

Interesting you have the easterly down there in Ashburton, it's a strong gusty Westerly here in Christchurch after being SW earlier.
Only dropped to 21C overnight, currently just pipped 28C here now.
On the current radar it's obvious there is a SW change down towards Ashburton, going by the windy app it's forecast to not come too much further north. So will probably be some local convergence down there today, unfortunately no surface moisture though.

The MS thunderstorm outlook was what I was thinking for tomorrow, certainly a chance for a severe cell or two.
Around mid afternoon we will probably see a few isolated showers ahead of the cold upper air, these could be heavy with a smaller risk of thunder on the first southerly.
It's the second wave at night which has the high risk.
Upper air is actually a tad colder now on -28c, you certainly would be pushed to see anything colder than that for this time of the year.
Natures own new years light show

Thanks for the update! I’m pleased to see that tomorrow’s main show will be at night as I’m working all day. Woohoo!

[David]

Extremely humid today, DPs around 22C and sometimes 23C

[mikestormchaser]

Yes I wouldn't be surprised about severe hail risk tomorrow evening for Canterbury given strong shear is also their tomorrow

[NZ Thunderstorm Soc]

Otago and South Canterbury look the place for a thunderstorm tomorrow afternoon/evening. A cold trough over the area.

I hope so unless the dreaded clagg moves in and stuffs things up
Back to that again today after warm day yesterday.

[NZ Thunderstorm Soc]

I like the way that MS say "A Hot Day" for Ashburton when it is only 18.3C at the moment.

[darcyplumb]

I like the way that MS say "A Hot Day" for Ashburton when it is only 18.3C at the moment.

It’s been cloudy and under 20C since about 10am this morning.

[NZ Thunderstorm Soc]

It’s been cloudy and under 20C since about 10am this morning.

Same here.

[Storm Struck]

I like the way that MS say "A Hot Day" for Ashburton when it is only 18.3C at the moment.

It’s been cloudy and under 20C since about 10am this morning.

That Southerly sure is making an impact further south, it did go a breezy southerly for about half an hour this afternoon.
But is back to the gusty NW and 27C.
Can see the convergence insect line on the radar sitting south of Christchurch.
It's not often this happens usually the SW boots the NW out.

[Richard]

Weak SW changes can at times not even make it this far inland. Been a lovely afternoon because the NW has lightened off, around 25deg atm

[NZ Thunderstorm Soc]

It started off fine and sunny after a mild night, overnight, but sadly the southerly came through around 9am and it's associated low cloud moved in from then on to become an overcast day with wind wind easing and becoming light from between south and east.Today's maximum was 22.5C before the southerly change this morning.
Will it be clagg or thunderstorms tomorrow with the next southerly change?
Watch this space.

[JP.]

Going to be spending NYE at a friends house at the top of mt pleasant. Looking forward to a bit of a show tomorrow evening. Will snap a few pics if I see anything exciting from the southerlie change.

[spwill]

Not expecting a thunderstorm here but afternoon/evening rain should clear Auckland before midnight, a warm humid evening.

[Razor]

The first of today's 3 course meal has gone through our camp at Kairaki Beach (Waimakariri mouth) with half an hour of spillover rain.

[Richard]

The first of today's 3 course meal has gone through our camp at Kairaki Beach (Waimakariri mouth) with half an hour of spillover rain.

Whats on the menu and at what time is the second course.

[Razor]

The first of today's 3 course meal has gone through our camp at Kairaki Beach (Waimakariri mouth) with half an hour of spillover rain.

Whats on the menu and at what time is the second course.

Weak southerly change for lunch and a stronger one for dinner

[darcyplumb]

Here’s todays info from MS

Fronts move northeastwards over the North Island today with bands of rain and possible thunderstorms. A southwest flow spreads over the South Island with rapidly cooling temperatures aloft.

In the North Island, there is a moderate risk of thunderstorms about northern and western areas from Northland to North Taranaki, and also about the central high country and Bay of Plenty, mainly this afternoon and evening, but for Taranaki this morning and afternoon. A low risk of thunderstorms covers other central North Island areas from Manawatu and Tararua District northwards. These thunderstorms will be accompanied by heavy rain with intensities of 10-25 mm/h range, and with a low risk of localised downpours in excess of 25 mm/h. However, for Waikato, Waitomo, Taumarunui, Taupo and the Bay of Plenty, there is a moderate risk of localised downpours of 25 to 40 mm/h. If any downpours do occur, they could cause surface flooding and make driving conditions hazardous. A Severe Thunderstorm Watch for downpours will is in force.

For the South Island, an upper cold pool will lead to increasing instability with thunderstorms and hail in some areas. There is a moderate risk of thunderstorms this afternoon and evening about Canterbury south of Rakaia, Otago and inland Southland, and about the remainder of Canterbury in the evening and at night. These thunderstorms will bring brief heavy rain of 10-25 mm/h, and hail mainly 10-20 mm diameter, however there is a low risk of larger damaging hail greater than 20 mm diameter. A few of the thunderstorms about Canterbury may be also be squally with localised wind gusts of 100 km/h.

A low risk of thunderstorms covers many other South Island areas as indicated on the chart.

No other thunderstorms or significant convection expected over New Zealand during this period.

[mikestormchaser]

The reliable BSCH GFS is down atm so haven't seen the latest models however have looked at some others and still seems to be thunder/ hail risk for eastern SI this afternoon/evening

[Razor]

Strong NW has sprung up here at the camp. Very blustery indeed