NZ Weather Forum

Metservice wrote: Issued at: 8:33pm Thursday 10 Oct 2013

Forecast amended 8:30pm Thursday and minor changes made to moderate risk area over North Island (now including coastal Waikato but not all of the Coromandel Peninsula).

The trough should move slowly across Fiordland and south Westland during the afternoon and early evening, with a low risk of a few thunderstorms. An associated southwest change is forecast to move through Southland and south Otago/Dunedin during this time. The combination of afternoon heating, cold temperatures in the upper atmosphere and surface convergence leads to a low risk of thunderstorms in this area.

An active front is forecast to move out of the north Tasman Sea tomorrow and across the upper half of the North Island at night. There is a moderate risk of thunderstorms over Northland, Auckland, coastal Waikato and northwest Coromandel Peninsula in the evening. These thunderstorms may produce localised heavy rain,and strong wind gusts of 90 to 110 km/h. In addition there is a low risk of these thunderstorms becoming SEVERE with damaging gusts in excess of 110 km/h and the possibility of small tornadoes. A lesser risk of thunderstorms extends further south to Taranaki and east to Bay of Plenty.

No thunderstorms are expected over the rest of the country.

jamie wrote:what are you expecting to get in the next 24-48 hours brian? in terms of wind gusts. If the weather is atrocious tomorrow morning i might go for a drive up the heads.

Manukau heads obs wrote: i.e analog dial one...like the one I damaged, LOL

Metservice wrote: ssued at: 10:22am Friday 11 Oct 2013

Unstable west to southwesterlies persist over New Zealand during the afternoon and early evening, along with very cold temperatures in the upper atmosphere. There is a moderate risk of thunderstorms from Auckland to Wanganui during the afternoon. These thunderstorms may produce localised heavy rain, small hail and strong wind gusts. In addition, there is a low risk of these thunderstorms becoming SEVERE and producing damaging wind gusts in excess of 110 km/h. There is a lesser risk of thunderstorms in the afternoon and early evening from Northland to northern Manawatu, also Bay of Plenty. Afternoon convergence zones are expected to set up in Wellington, south and coastal Wairarapa, and Hawkes Bay and Gisborne north of about Wairoa. In these areas, scattered heavy showers and small hail are possible along with a low risk of thunderstorms.

Heavy showers should quickly ease over Westland and Buller into the afternoon,but there is a low risk of a few thunderstorms there at first.

Afternoon convergences are likely to form over Southland, eastern Otago, the Canterbury coast and Plains, and eastern Marlborough. In these areas there is a low risk of thunderstorms through to early evening, however the risk is considered moderate in eastern Otago during the afternoon. These thunderstorms may produce localised heavy rain and small hail.

No thunderstorms expected over the remainder of New Zealand.

Manukau heads obs wrote:I see some CB's are starting to fire ahead of the front...which is building into the tasman like a giant wave

jamie wrote:
Brian you'll have a great light show tonight as it approaches late tonight.