At the outset I advise that storing wine in warmer temperatures is not a problem unless you intend keeping the wine for longer than about 2 years. Most people talk about cellaring wine but do not actually carry it out. Hence, for most people, cellar/storage temperature is simply not an issue of concern. That does not stop people inquiring earnestly about the subject though!

Wine industry personalities report that the most commonly asked question from consumers is "will this wine age well?". Link to this the theory that approximately 90% of wine sold in Australia is consumed within 3 hours of purchase. In other words, most people but their wine on their way to a party or "BYO" restaurant. It seems that if a wine is a good ageing proposition then a purchaser will buy it to drink that same evening! Most people who do keep wine at home have a few dozen on hand for meals and occasions. They consume their stock readily, replacing it regularly. The longest period that they store a bottle might be 6 - 12 months. In this situation, storage temperature is not an important issue provided that the wines are kept in a cool part of the house which has a fairly constant temperature.

If wine is to be stored seriously ie. fine wine is being deliberately kept for several years, then temperature fluctuations are a concern. Frequent and sudden temperature changes must be avoided. The ideal cellar temperature is about 12 - 15 degrees but a cellar in northern Australia with say a range of 20 -24 degrees is fine and certainly better than one where the temperature, although lower, varied significantly. Some southern inland parts of Australia have daily temperature fluctuations in spring and autumn of 0 -20. The average is low but the repeated changes can play havoc. If you store wine, you should use a maximum-minimum thermometer and keep an eye on the range which exists in your cellar or storeroom. Fluctuations of temperature cause a build up followed by a lowering of internal pressure on the cork. If repeated cyclical loading of the cork occurs, then it losses its elasticity and gradually leaks, letting air into the bottle. Air is the enemy of wine until it is ready for drinking.

If the ambient temperature of the area where wine is stored is warmer, then the wines will age more quickly than a cooler cellar. When wines age, they deepen in colour (ie. white wines become a deeper gold colour and reds become a brick-brown red colour). They also lose acidity and sharpness and they become mellow with a more soft vicious mouthfeel. Most Australian whites are better after a year at least, of age in the bottle. Most whites are good until about five years of age and then only the top quality wines will continue to improve. Reds are good for a bit longer, say seven years, although quality wines will age for longer. Australian wines are made with good lively grape characters and many are best drunk at about 2 years age. Beyond this they lose their freshness of flavour. For example, many chardonnays have a limes and peach flavour which disappears once the wines exceed four or five years.

Better quality Australian wines will age well beyond 4 years even in warmer climates. Care is needed beyond 7 or 8 years to keep the temperature cool.

A fair method of insulating wine is to keep it in its carton.

Winemakers who visit warm regions of Australia often comment on the pleasantness of a wine which has been kept in the warmer climate for a few years. Its rate of development has speeded up and it gives them a good idea about the future taste of wine stored back at the cold winery.