The 00Z in regards to tomorrow PM has the moisture and resulting convergence a bit further north into central western Waikato than the last few runs.
The High DP's and Warm SFC Temps are making up for the warmer (-12°C) upper level temps. Metservices Outlook in regards to Sunday:
Of note: the 00Z GFS is forecasting serious instability come Monday, I am questioning it at this stage, but tomorrows subsequent rounds will hopefully firm up more of a reasonable forecast.Metservice wrote: Issued at: 9:08pm Saturday 16 Jan 2016
Chart reviewed at 9:05pm Saturday and a low risk area added to Northland and the moderate risk area over the central North Island increased to high, but with rainfall intensities now not expected to exceed 25mm per hour.
Afternoon heating pushing temperatures into the upper twenties is expected to lead to quite strong wind convergences over the central North Island and central and northern parts of the South Island.
There is a high risk of afternoon and early evening thunderstorms triggering from north Taranaki and Taumarunui to the central high country to just east of Taupo. These are expected to be fairly slow moving and so have the potential to generate localised rainfall rates in the 10-25mm/hr range, and small hail. There is a surrounding lower risk of thunderstorms in a wider area over Northland and from western Waikato to the eastern Bay of Plenty ranges and south to the Tararua Range as depicted on the chart.
Also during the afternoon, there is a moderate risk of afternoon and evening thunderstorms over inland parts of southern Marlborough, giving local rainfall rates of 10-20mm/hr. A wider lower risk extends over other inland parts of Marlborough, Nelson and about the main divide to about central Westland.
In addition, in the far north of Northland, and over northern parts of Nelson,there is a low risk of elevated thunderstorms developing at night.
Elsewhere, no thunderstorms or significant convection expected.