NZ Weather Forum

Razor wrote:Agree its similar to june 2012 system

If it was mid winter and not mid spring we would be seeing snow to sea level no doubt!

Will be interesting to see how much snow in the passes and mt hutt by morning. 35mm so far and 3 degrees. Was some sleet earlier in the heavier band. Lighter falls ATM but steady. Should get over 50mm for the event.

CHCH Weather Chaser wrote:Will be interesting to see how much snow in the passes and mt hutt by morning. 35mm so far and 3 degrees. Was some sleet earlier in the heavier band. Lighter falls ATM but steady. Should get over 50mm for the event.

What do you think for snow levels Leighton?

I think snow as low as 150m with sleet possible to near sea level in the heavier bands. These convective systems can be unpredictable.

CHCH Weather Chaser wrote:I think snow as low as 150m with sleet possible to near sea level in the heavier bands. These convective systems can be unpredictable.

Agreed, had reports of flurries down to about 120m!

An outside chance but worth noting in the surface maps shows at the moment the general bulk rainbands coming down from the north, but with the low shifting into the southern ocean overnight this whips up a strengthening cold S-SE flow.
With this its hard to say there could be a window of sleety/flake fall to near sea level maybe around 4-5am for a short while, but after that I think the city tomorrow will generally see lighter patchy falls until late afternoon with heavier unfortunately rain/snow falls inland but with the freezing levels rising by afternoon.

Inland areas must be getting a good dusting above about 300m right now, this will melt fairly quickly with the incoming NW system into Thursday and new low feature Friday.

Raining steadily and 4.4 degrees at present.

Not a lot more rain overnight,69mm in total

Rained most of the night here, around 5cm of snow on the ground... Trying to snow again now though ! 60 mm for the event!

Interesting warm advective snow event.

20mm of rain here for this event, Snow level looks to be around the 500m mark.

Intermittent rain continues. Just had a hail shower too.

Wow over half a meter of snow in Arthurs pass township and still snowing hard by the looks of it.

Nasty-looking ragged cloud coming across, wind has risen and rain resumed; it's got quite dark and gloomy.
6.0 deg.

Little rattly shower of hail just now.

Can someone please explain to me how we got more snow at 300m asl in this event then the June event this year (mostly just rained) when the temperatures at 850hpa (1500m asl) was 2C warmer for this event? Makes no sense whatsoever!

Bradley wrote:Can someone please explain to me how we got more snow at 300m asl in this event then the June event this year (mostly just rained) when the temperatures at 850hpa (1500m asl) was 2C warmer for this event? Makes no sense whatsoever!

This is due to the fact that is was a warm advection event, where warm moist air passes cold southern air! It means that as the moisture passes through the cold air it obviously freezes and falls as snow! It means that it can be warmer and still snow to low levels!

Thanks mate, and this didn't happen in June's event obviously?

Nice in Reefton @ 11. Beautiful between Lewis and Hanmer, green grass just showing through white in river valley. Cloud base high enough to still have good visibility.

A few playing in roadside snow. Was dry at Marble Point at 1pm but soon met driving flakes near summit. Spitting/drizzle in Culverden, 8C

Bradley wrote:Thanks mate, and this didn't happen in June's event obviously?

It did, although the difference is that June 6th 2012 was an event which occurred in winter, while this event happened in mid spring.

I got 52.4mm for the event bringing the total for the year to 632mm.

Skywatcher wrote:I got 52.4mm for the event bringing the total for the year to 632mm.

The farmers down there will be loving that kind of rainfall at this time of year.

Yes a great time of year to get such a good soaking

Skywatcher wrote:I got 52.4mm for the event bringing the total for the year to 632mm.

65.8mm for the event here in Finlay's road.

That suprises me that your minimums aren't much lower then the airports NZ Thudnerstorm, I would have though being another 70m higher up in elevation then the airport and being on the south side of main west coast rd (away from the river and any NW breeze springing up from it) that you would be on average 1C colder at night then the airport?