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The Texan summer is long and hot. This year, particularly so. In some places, people have taken refuge in public libraries just to enjoy the air conditioning. And among those closely tracking the weather, besides overworked meteorologists, is a whiskey distillery in downtown Waco.

Perched on the roof of Balcones Distillery is a complicated bundle of instruments. There’s a thermometer, barometer and humidity sensor. One component that measures wind speed spins freely in the breeze. The system can quantify rainfall. Each of the distillery’s warehouses at other locations in the state, where the spirit lies maturing in casks for years, also has one of these rooftop weather stations. There are temperature sensors on each floor, too.

“Theoretically, all this information would let us know the best time of year to make a specific kind of spirit and the best place to put it,” says Jared Himstedt, head distiller at Balcones. The distillery is relatively young, having been launched in 2008, but has been making a name for itself producing American single malt whiskey and other spirits.

“It’s a little bit of really throwing the kitchen sink at the problem and reverse-engineering which barrels turned out the way you wanted,” Himstedt says.

He’s not sure whether all of the data will prove to be useful in his quest to understand how the unforgiving Texan environment influences distilling and maturation. But he and his team have found that simply tracking temperatures alone has already helped them determine where to place casks in their warehouses in order to encourage the development of certain characters – from light and mellow notes through to richer, spicier profiles.

Higher temperatures can induce a stronger interaction between the spirit and the wood of the cask in which it ages. And tracking temperature is perhaps particularly important in a place like Texas because the difference between the bottom and top of a warehouse, as confirmed by Balcones’ data, can actually be quite significant. Conversely, in Scotland, given the country’s mild and temperate climate, that within-warehouse difference is far less pronounced.

Whiskey is tied to climate. It ages differently depending on precisely where the casks are laid down – both where in a warehouse, and where in the world. This effect is made obvious by the “angel’s share”, the volume of whiskey lost to evaporation during ageing. But climate helps to determine how much of the angel’s share is alcohol and how much is water, because they evaporate at different rates.

Read more: How whiskey is shaped by the weather and climate