Fair Weather Winemaker

12 April 2026

Cyclone Vaianu is making landfall in New Zealand this weekend.  On its journey from the Pacific it's been pushing high humidity into the country, which means it's been lovely and warm but personally, it does affect my work in the winery. 

Here are some reasons why, which if you're a winemaker too, may explain things or give you things to consider.  Especially with the frequency of wild weather these days...

For one, I haven't been able to label any of my wines - when there's high humidity, the labels may go on smoothly but then 15 minutes later the labels will be ripply and bubbling as the moisture interferes with the adhesion.  The same thing happens during winter if I don't get the bottles to room temperature before putting the labels on.  So I try to only label when the temperature is ambient inside and out, which is not always do-able!  If I must label in winter then I'll bring the bottles inside to the lounge for a couple of days where it's warmer, and then label.  

Note; I don't have a labelling machine, maybe they mitigate this issue?  Therefore, this info is regarding hand labelling!

Another thing to consider when the weather is stormy, is that barometric air pressure has an effect on fermenting wine.

Low pressure creates air to rise which can make our wines look more active and/or the sediment is more floaty.  You may find your airlocks start burbling away more.  Racking a wine during this time can be more work than it needs to be as you try to navigate the sediment, and bottling a wine can be risky during this time too - unless it's a sparkling, in which case the weather may work in your favour! 

On the other side of the coin, when barometric pressure is high, the air is sinking (usually resulting in fair weather).  Because the air is sinking, it presses on the wine and CO2 leftover from the fermentation process is crushed, so bubbles don't form in the liquid, or in the lees below.  A pretty sound time to do your racking and bottling.

Here's a link that explains it a bit more (plus other interesting things 😉)

We could also go into the "right time" to do things in the winery based on what the moon is doing (which I do do sometimes) but we'll leave that for another post!

At the end of the day though, we can't always wait for everything to be aligned perfectly and if you've got stuff to do, sometimes you've just got to get onto it whatever the weather.

Speaking of, a lot of people in New Zealand right now are getting evacuated from their homes, my thoughts are with you (it hasn't reached us yet) especially to those that have been through all this before, recently, and during Cyclone Gabrielle.  Aye carumba!