Comparing winter and summer southerlies

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tich
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Comparing winter and summer southerlies

Unread post by tich »

(I thought I'd put this in a new thread)
Foggy Hamilton wrote:
People always refer to this as 'wintry' weather, but if we were in mid-early july and we got this same southerly blast with hectopascals, temps @ 11am would be below freezing in places like Waiouru, Alexandra, Queenstown etc. (Queenstown on 4c at 11am to note)
Auckland would be on about 9c, Hamilton 8c, Taupo 5c, Napier 7c, Wellington 7c, Christchurch 3c and snow, Dunedin 2c and snow, Invercargill 2c and snow...

So therefore, this is summer-like weather but we're very unlucky to have all these south to southwesterly situations



When cold outbreaks occur in summer, I like to imagine what an identical or very similar outbreak would be like in winter. I would guess that this last weekend's chilly blast, had it occurred in winter, would've produced very cold temperatures and widespread low-level snow in the nature of the polar southerlies of July 2003 and August this year. In this case, snow on the hill country just south of Auckland could even be a possibility, as the very cold air has still been moist and unstable as it affected the upper North Island.
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Willoughby
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Unread post by Willoughby »

We all know southern air-masses are dry, but are they drier in Summer or Winter? One would assume summer southerlies are more humid with warmer sea temps...

I think im digging myself into a hole :oops:
tich
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Unread post by tich »

A big difference between winter and summer cold southerly outbreaks is the thunder and hail activity that's often induced by cold, unstable air moving over land warmed up by the sun. That's probably why you don't see winter hailstorms in areas like Nelson when cold southerlies hit.
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Michael
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Unread post by Michael »

If its really cold(than normal) in winter we would tend to get more S and anticyclones :idea:
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