NZ South Island forecast 5th August

By MountainWatch.com - 5 August 2010

South Island NZ Forecast Analysis
Thursday 5 August, 2010

By David Winterburn

Summary:
The rain over the last weekend has left snow conditions very spring-like, hard with a significant crust. Ski fields will be looking toward the incoming fronts and hoping for some snow later in the week. At this stage Thursday and Friday will remain fine, with cloud increasing in western areas late Friday and rain developing. This will continue over the weekend, with a cool S/SE flow bringing some snow to around 1300m.

Synoptic Outlook:
A thin ridge of high pressure (1013hPa) sits over the island delivering fine weather to most of the island on Thursday and Friday. Late Friday sees a brace of weak front's brush past the lower part of the island delivering some showers to western and southern regions.

Out to the west a low (1008hPa) develops in the Tasman and looks to hit the island Saturday. As it attempts to push onto the island a larger and more dominant high (1029hPa) undercuts it from the SW and pushes it northwards towards the upper South, lower North Island. The end result is that the two systems are going to deliver a cold S/SE flow to southern and eastern areas of the island over the weekend.

Thursday 5 August:
Mainly fine, with valley fog in the mornings.

Friday 6 August:
Mainly fine however rain developing in the west and about the main divide in the evening.

Saturday 7 August:
Rain and snow falling down to about 1300m in southern and eastern areas. Gradually clearing in the south by the evening. Cold, blustery S/SE winds.

Sunday 8 August:
Mainly fine in the west and south of about Mt Cook except for the odd shower. North of about Mt Cook easterly winds and rain/snow showers.

Canterbury:
Thursday and Friday look fine for Canterbury with the 'real' weather arriving on Saturday. A S/SE change looks to sweep up the island, delivering some new snow to most eastern areas. This could be excellent news for Mt Hutt, which does very well out of these S/SE storms. If the forecast models come true I'm picking 10-20cm for them. Make sure you check your reports before you head up though, as there visibility and strong winds might be an issue.

Southern Lakes:
Thursday and most of Friday look good for the Southern Lakes with fine weather. On Friday afternoon some frontal cloud might spill over the divide delivering a 'skiff' to Treble Cone. The weekend is shaping up okay it terms of new snow as well. The S/SE change on Saturday should deliver some snow to most of the southern fields although it could be windy at times. It's sort of shaping up to one of those 5, possibly 10cm storms for them. Sunday should see the start of some clearing skies.

Extended Synoptic Outlook:
Mainly fine in the west and south although cloud be some snow showers from some strong easterly winds.

Be sure to check the daily condition Reports and forecast info and maps daily to keep your finger on the pulse.

Resorts that may be of interest