17-18 June

Outcome: Too warm

Outcome

Perisher Valley claimed 2 cm snowfall, which looks pretty accurate. We’re now officially at zero snow depth at Spencers Creek. There’s still a bit of snow high on the Main Range and under high-quality snow making equipment, but that’s it.

JMA precipitation inferred from satellite imagery

JMA precipitation inferred from satellite imagery (rain!)

BOM surface chart archive

Update

This is looking more marginal now I’m afraid. The shape has shifted slightly so that Thursday’s feed is a bit more southeasterly and less cold, and the properly cold air doesn’t arrive until Thursday night, too late for most of the moisture:

US model GSF for 4:00am Thursday, as plotted by NZ weather service metvuw.com

Sans some snow tonight, Thursday’s depth at Spencers Creek will be zero, in the bottom 20% of the historical record. Bring on next week

Original post (15 June)

This has finally settled. On the tail of this week’s nasty tropical feed is a little southerly blast that may bring as much as 20 cm. That’s sorely needed, because the natural snow depth is near as not to zero at the moment:

US model GSF for 4:00am Thursday, as plotted by NZ weather service metvuw.com

By Thursday, the remnants of the tropical feed are concentrated in the heavy rain band off the east coast, but the action is sucking in Antarctic air behind it. There’s not a lot of moisture there, but there’s not none either.

2 comments to 17-18 June

  • Warrie

    Hi Gerg, long time no communicate. Official zero at Spencers from am reading with snow starting in late pm. Its a rerun of July 2010 – zero followed by a good dump. Jane’s confident of 50 cm – that’s over a third of your 140 plus prediction for season 2015. Enjoy…. Warrie

    • Gerg

      Hi Warrie. Seems Jane’s 50 cm has evaporated. A pity; she’s usually on the money.

      Anyway 50 cm of fall is not 50 cm of peak depth. The ratio is about 3*, so 50 cm of fresh is only good for average about 15 or so centimetres in the peak depth.

      (* Fresh here seems to average about 0.1-0.15 t/m³, and the average snowpack density near the peak is about 0.4 t/m³.)