On Saturday 17 October, the roasting bulletin logged a clear sky, 10 to 15 °C, 70% humidity and a north wind at 19 km/h. On Sunday the sky closed over: 8 °C at 9 am, 10 °C at 1 pm, a light north-easterly. Meteo Koffie is an open-air coffee roastery, and anyone who stood by the flame on both days felt the difference on their own hands. Below you will find where we are, when we roast, what you see at the stand, what the bag tells you, and a five-minute test to run at home with a bag bought from us.
What Meteo Koffie is
Meteo Koffie roasts specialty coffee outdoors, on weekends only, at Marché de l'Abattoir, Anderlecht. Green coffee arrives in jute sacks, goes into Golden's drum, drops onto the tray and cools in the open air, a few steps from the people buying it. You can watch every stage, from sack to bag.
We roast small lots, a few sacks per weekend, and each lot is roasted on a single day. Every bag carries the day and the weather it was roasted in. We call this weatherroir: the weather becomes part of the lot's identity, alongside the origin, the day, the place and the person who roasted it.
That person is Laurent. Each morning Laurent reads the sky, then sets the fire and the timing on Golden. When the wind blows or the air cools, Laurent corrects the flame in small steps. When the air is damp, Laurent lets the roast run a little longer. The taste Laurent aims for in the cup stays the same; the route to it changes from one day to the next.
Golden and the flame
Golden is our roaster: a drum heated by a gas flame, working under the open sky. It rumbles, smokes and heats up in front of passers-by.
In a closed workshop, the air around the machine sits at roughly the same temperature every day. Outdoors, the drum gives heat away to the surrounding air, more so when it is cold and when the wind blows. We roast on Saturdays and Sundays, during market hours, so Laurent works with whatever weather each weekend brings.
On Sunday 18 October the bulletin showed 8 °C at 9 am, 10 °C at 1 pm and 11 °C at 5 pm. Three degrees in one day means the fire that suited the first lot is too much for the afternoon lot. Laurent corrects in small steps, keeping the same taste target. We explained the mechanism in detail in the article on the flame in cold weather.
The ritual of the three bells
Every roast has three bell strikes: permission, fire, harvest.
- First bell, permission. Before the first batch, Laurent rings the bell and asks the machine for permission, with words along the lines of "let me begin". The ritual is a request, and the decisions at the fire stay with the person.
- Second bell, fire. The beans reach first crack, the metal sings, the smoke changes colour. Laurent listens, smells and checks the colour to choose the moment to stop.
- Third bell, harvest. The lot drops onto the tray and cools for about five minutes in the open air. That is when people gather around the tray.
To see all three, come in the morning and stay by Golden for one full lot. Five minutes of cooling is enough time for a question about an origin or about your recipe at home.
Where to find our open-air coffee roastery
Saturday and Sunday, 6 am to 3 pm, at Marché de l'Abattoir, Anderlecht. Monday to Friday the stand is closed. We are at the exit of the Manufakture car park, Quai de l'Industrie 168. By metro, get off at Clemenceau station (lines 2 and 6), the closest to the market.
The market is large and fills up fast at weekends. Follow the smoke: on clear days you see it from far off, and on windy days the smell of roasted coffee reaches you before the smoke does.
At the stand you can buy 250 g bags from the day's lots, whole bean or ground for your method: espresso, filter, moka pot or French press. If you cannot make it to the market, the online shop stays open: we roast on Saturday and ship on Monday.
The lot passport: what the bag tells you
Every lot has a passport: the roast date, the lot code and the air at the time of roasting. Here is a real example, the Brazil Cerrado roasted on Sunday 18 October:
- Roasted in weather: cloudy
- Roast date: 18/10/2026
- Lot: MK-261018-CLC-BRE
- 8 °C, humidity 91%, 1027 hPa, wind 2 km/h
You will find the same line on the Brazil coffee page. The whole day is in the roasting bulletin for 18 October (in French): 8 to 12 °C, overcast, 81% humidity, north-easterly wind at 8 km/h, 1026 hPa. The product page records the air of the lot; the bulletin follows the whole day, with the temperature at 9 am, 1 pm and 5 pm.
At home the passport does two jobs. The roast date tells you how many days the coffee has rested, so you know when to open the bag. The lot's weather helps you compare two bags and understand why your recipe shifted a little. For the moment you switch bags and the coffee comes out differently, we wrote the new bag test step by step.
The Friday Roast: roasting seen by a team
For companies there is The Friday Roast, a free session on registration, on Saturdays at 9:30 am and 2 pm, at the stand. It lasts 45 to 60 minutes and takes groups of 5 to 15 people. Participants hear the day's weather read aloud, watch how Laurent decides at the fire, go through the bell ritual and taste three coffees, including the lot that has just come out. Everyone leaves with 50 g of the day's lot.
Registration is on b2b.meteokoffie.com. You will also find Meteo Office there, monthly coffee for the office, from 2 kg a month for teams of 5 to 15 people.
The Club, for coffee at home
The Meteo Club is the home subscription: your bag is roasted every month without reordering. Pick it up at the stand on roasting weekend or get it by post on Monday, anywhere in Belgium, with the real weather of the roast day on the bag. Plans and details are on the Meteo Club page.
If you mix your own blend from several origins, use our blending guide.
The home test: how fresh is your bag
You have the passport, so you know the roast date. Freshly roasted coffee releases carbon dioxide, and with filter coffee you can see it: pour a little water over the grounds and the bed swells and bubbles. As the days pass, the swelling gets smaller. The test takes five minutes.
You need 15 g of coffee ground for filter, a filter (V60, Kalita or whatever you have), a scale and water just off the boil.
- Put the coffee in the filter and level the bed with a gentle shake.
- Pour 30 g of water, just enough to wet all the grounds.
- Watch for 30 seconds: how high the bed rises, how big the bubbles are, whether a dome forms.
- Keep pouring up to 250 g of water and drink the coffee.
- Write on the bag how many days have passed since the roast date and what you saw.
- Repeat a week later, with the same recipe and the same grind setting.
How to read the result:
- Big dome, lots of bubbles, harsh or sour taste: the bag is very fresh. Give it three or four more days and test again.
- A bed that swells gently and a balanced cup: you have hit the right window for this lot. Write the day down, so next time you know how many days to wait before opening the bag.
- Hardly any bubbles although the bag is only a few days old: check whether the coffee was ground in advance or the bag was left open. Ground coffee loses its gas much faster than whole beans.
- No bubbles and a flat taste after several weeks: time for a new bag. The product page recommends drinking the coffee within four weeks of opening.
If you have two bags of different ages, one roasted a week ago and one three weeks ago, test both on the same morning. The difference in the dome shows you with your own eyes how much the date on the passport matters.
Saturday and Sunday, Marché de l'Abattoir, Anderlecht.
Brut. Sauvage. Imprévisible.
