Fog and coastal windshift effect!!

Archive of NZ Weather & Climate
Forum rules
These topics are a read-only archive and may be subject to out-of-date information.

For today's weather discussion head to: New Zealand Weather & Climate
User avatar
Storm Struck
Posts: 4865
Joined: Wed 17/11/2004 21:25
Location: Belfast Christchurch
Has thanked: 23 times
Been thanked: 375 times

Fog and coastal windshift effect!!

Unread post by Storm Struck »

I came across a rather interesting situation with the sea breeze when up at Kate Valley today.
It was blowing a strong N-NW warm wind with sunny skies up there right from when we arrived at 10am.
However as we got closer to the sea the fog lay in pockets stuck funneling up and around the valleys.
But what I had never encounterd before was when we stood out on a ridge above the fog, the wind would be blowing a warm strong NW then suddenly flick to a colder eastery wind and i mean about a 5-6C difference.
Then it would flick back warm NW again, but just the actual feeling of such an abrupt temperature change was rather an unusual feeling.
I also noticed as the fog was clearing out at sea during my lunch break, that with the winds shifting from a NW-E there were what I would call Fognado's ( just fog spinning high into the air like a funnel) 8) .
I was surprised how long that Fog hugged chch today especailly with the NW flow kicking in.
Cheers
Jason.
Canterbury, home of good rugby and severe storms
User avatar
David
Posts: 7587
Joined: Sat 18/08/2007 21:02
Location: Howick, Auckland
Has thanked: 416 times
Been thanked: 832 times
Contact:

Re: Fog and coastal windshift effect!!

Unread post by David »

Could be that the NW change coming in encountered the easterly of similar strength, and they battled it until the NW became stronger and prevailed.

This alternation of E and NW of course creating eddies and currents of air around the local topography, resulting in the fog you saw swirling around before blowing away and dispersing with the drier NW.
Image
Locked