As someone born and raised in the warm and humid climate of Guangdong, I can tell you—winter brings two annoyances: never knowing what to wear, and occasionally, coffee that suddenly tastes “off.”
So it’s crucial to identify the culprit and fix the issue before it ruins your brew.
Today, based on real experiences from my café and feedback from customers, I’ve put together a list of common winter brewing problems and how to resolve them.
1. Rapid Drop in Water Temperature
It’s winter, so of course we have to talk about water temperature. Because indoor environments are much colder, both the water inside the kettle and the water in your gooseneck pot cool down significantly faster than in other seasons.
I once ran a test:
Using 92°C (197.6°F) water to brew a pour-over in summer, the leftover water stayed at 88–89°C (190–192°F) after 2 minutes.
But in winter? Using the same 92°C water for the same 2-minute brew, the remaining water dropped all the way to 84°C (183°F).
Not only does the kettle lose heat faster, but the dripper—constantly exposed to air—also drops 1–3°C (1.8–5.4°F), meaning your actual extraction temperature in winter is much lower. As a result, your brew may taste more acidic or thin.
How to fix it:
Increase your brewing temperature by 2°C (≈4°F).
For example, if you usually brew a Kenyan “little tomato” flavor profile at 92°C, bump it to 94°C in winter to compensate for room temperature.
If you’re not using a temperature-controlled kettle:
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Empty any cold water from your kettle first
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Preheat the kettle with a small amount of boiling water
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Then add your brewing water and measure
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Fill the kettle with more water than usual—larger volumes cool more slowly
2. Simple Ways to Keep Your Equipment Warm
Winter doesn’t just cool the water—it cools every piece of equipment in your workspace. Since your dripper, server, kettle, and brewer all stay icy cold, extraction behaves very differently from warmer seasons.
Here are a few heat-preserving tips:
Preheat drippers and servers thoroughly
Ceramic, glass, and metal drippers absorb far more heat than plastic ones. They will literally steal heat from your brew water.
So if you use any of these, rinse your filter paper with at least 50g of hot water. This:
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Reduces heat loss to the dripper
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Preheats the server at the same time
Warm your gooseneck kettle spout
A gooseneck kettle has a long, thin neck that stays cold. During bloom, the first water that passes through absorbs this cold and loses heat instantly—meaning your actual extraction temperature is below your target.
To prevent this:
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Pour out a small amount of water to preheat the spout
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Then start your bloom
Lower your pouring height
Higher pours expose your water to more air, cooling it faster and reducing extraction.
In my shop, I normally pour from a height of 4–5 cm with a slow, gentle stream.
In winter, I drop that to 2–3 cm and pour slightly faster to retain heat.
3. Excess Static in Coffee Grounds
We all learned in school that dry environments cause static buildup. Winter air is cold and dry, which means static becomes a big problem—especially for coffee grounds.
Every winter, I start hearing crackling sounds when touching metal equipment. That’s winter reminding us that we need to pay attention to two issues: clumping and grinder retention.
Static causes grinders to “eat” coffee
When you grind beans, heavier particles fall straight into the catch cup. Fine particles, however, stick stubbornly to the grinder walls in winter.
In humid seasons, fines fall normally.
But in dry winter air, static causes the grinder to retain a surprising amount of fine grounds, leaving you with noticeably less coffee in your cup.
Fix:
Use a blower designed for coffee grinders, or a clean brush, to dislodge the stuck grounds.
Clumping increases with finer grind settings
Static makes fine coffee particles cling together, forming small or large clumps. These clumps lead to uneven extraction, especially in pour-over brewing.
The fix is simple:
Use a toothpick or a needle distributor to break the clumps apart before brewing.