Thunderstorms and possible Tornadoes - 16th May

Tornado Tim · Unread post by **Tornado Tim** » Sun 15/05/2016 17:58

In the Metservice office at the Forecasters Desk, discussing tomorrows forecast.

Some really good stuff coming.....A very good trough going to come through tomorrow PM with high CAPE, and fairly good helicity.
EC Model indicating 1200-1400 j/Kg mixed CAPE and -6 LI which is very high for New Zealand.

Will be in the Metservice office again tomorrow. Will be very interesting day for sure, the office will be a hype of activity. Leaving Wellington around 6 PM and based on the EC the trough will be coming into the Waikato around the same time I am arriving in Hamilton, will be very interesting flight for sure if the forecast timing is correct.

Manukau heads obs · Sun 15/05/2016 17:58

good stuff Tim

NZ Thunderstorm Soc · Sun 15/05/2016 20:01

Another Ross tornado sequence, somewhere?

NZ Thunderstorm Soc · Sun 15/05/2016 22:02

Just read the latest thunderstorm watch for western areas. Look like quite severe

Thunder081 · Unread post by **Thunder081** » Sun 15/05/2016 22:50

NZ Thunderstorm Soc wrote:Just read the latest thunderstorm watch for western areas. Look like quite severe

Yeah it's rare to see a moderate risk for severe thunderstorms for Kapiti, the last time I saw them issue one for kapiti was on the 7th of March 2015.

Richard · Unread post by **Richard** » Mon 16/05/2016 06:50

Great light show over the mountains this morning, well worth getting up early and standing out in the sheep paddock to watching it.

Nev · Unread post by **Nev** » Mon 16/05/2016 07:10

Yeah, Blitzortung has been going ballistic overnight as this frontal system moves up the West Coast…

NZstorm · Unread post by **NZstorm** » Mon 16/05/2016 07:26

300mb divergence with this system will favour lightning development.

The best CAPE on the gfs is about 800j/kg. Thats big CAPE for an early winter style set up.

I see squally winds tonight for the North Island, not much tornado potential due to the lack of directional shear.

Manukau heads obs · Mon 16/05/2016 08:20

that trough is certainly sharpening up on the sat image
looks like plenty of CU cloud in the north tasman to become more active and move down into the NI this evening

dogmelon · Unread post by **dogmelon** » Mon 16/05/2016 08:40

NZ Thunderstorm Soc wrote:Another Ross tornado sequence, somewhere?

Yip, Ross. Check out whats bearing down at around that area on the radar.

Nev · Unread post by **Nev** » Mon 16/05/2016 09:05

MS's morning T-storm Outlook update for today just out. Moderate risk of tornadoes has shifted further north...

MetService - Thunderstorm Outlook

Valid to: Midnight Monday 16 May 2016
Issued at: 8:55am Monday 16 May 2016

A series of active fronts are expected to move northeast over the country today and early tomorrow. Combined with cooling temperatures aloft, there is a high potential for thunderstorms and severe convection in many areas.

The highest risk of thunderstorms is in the west of both Islands, covering Stewart Island, Fiordland and southern Westland this morning and afternoon, the remainder of Westland, Buller and northwest Nelson for most of the day and from Kapiti Coast to southern Northland from this afternoon until tonight. These thunderstorms are likely to be accompanied by localised heavy rain, strong wind gusts, hail and possibly small tornadoes. There is also a moderate risk of SEVERE THUNDERSTORMS bringing wind gusts above 110 km/h or damaging tornadoes,to Stewart Island, Fiordland and southern Westland this morning, the remainder of Westland, Buller and northwest Nelson this afternoon and from Kapiti Coast to southern Northland this evening.

Outside the areas mentioned above, there is a moderate risk of thunderstorms spreading quite a way east over both Islands. Over the South Island, this risk is for most of the day, but in the North Island the risk is from the afternoon south of Lake Taupo and from the evening further north. Also, not shown on the chart due to space restrictions, there is a low risk of SEVERE THUNDERSTORMS bringing wind gusts above 110 km/h or damaging tornadoes for Northland, Great Barrier Island, the Coromandel Peninsula and Bay of Plenty.

As a cold southerly change move up over Clutha and Dunedin this afternoon there is a low risk of thunderstorms.

MetService T-storm Outlook Map for May 16.gif

mikestormchaser · Unread post by **mikestormchaser** » Mon 16/05/2016 09:09

No risk for coastal eastern south island but I'd have a low risk for coastal Otago and Canterbury today aswel. Southerly buster storm if anything.

Manukau heads obs · Mon 16/05/2016 09:27

YES
waiting in anticipation

(but not that I am wanting damage or loss of life to occur, just to be clear)

Lunar2 · Unread post by **Lunar2** » Mon 16/05/2016 09:34

Favourible for tornadoes still? When could it be expected to move into kapiti?

Manukau heads obs · Mon 16/05/2016 09:45

Blitzortung working well

http://en.blitzortung.org/live_lightnin ... php?map=21

matttbs · Unread post by **matttbs** » Mon 16/05/2016 09:50

Thunder here which I wasn't expecting

jamie · Unread post by **jamie** » Mon 16/05/2016 09:54

Looking awesome. Shame it's not coming in around 3pm. I would have sat at yours Brian.

Manukau heads obs · Mon 16/05/2016 10:08

yeah, was thinking the same thing, its going to arrive after dark here
but will be good for lightning display

Richard · Unread post by **Richard** » Mon 16/05/2016 10:12

Great to see they have the moderate risk further east now closer to here.

spwill · Unread post by **spwill** » Mon 16/05/2016 10:19

The lines are better coming through at night for lightning observation , nice line out there currently, hopefully it all holds up.

Orion · Unread post by **Orion** » Mon 16/05/2016 10:52

matttbs wrote:Thunder here which I wasn't expecting

Have heard a couple of distant rolls of thunder here in Ashburton also.

NZstorm · Unread post by **NZstorm** » Mon 16/05/2016 11:31

spwill wrote:The lines are better coming through at night for lightning observation , nice line out there currently, hopefully it all holds up.

I agree, we want the front to come through at night. Its the lightning thats the photographic opportunity.

500mb jet stream chart here for this evening. An 80knot jet!

03Stormchaser · Unread post by **03Stormchaser** » Mon 16/05/2016 11:39

A nice lowering was filmed coming ashore near the Greymouth Aerodrome earlier this morning. https://www.facebook.com/nzstormchasers

Sent from my Nexus 5

Manukau heads obs · Mon 16/05/2016 11:56

baro starting to fall here quickly now

Richard · Unread post by **Richard** » Mon 16/05/2016 12:14

Thunder heard to the west and rain starting to fall also.

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