El Niño is here, and it's shaping up to be a big one. Our Green Buyer explains what it is and why he's watching it closely.
Update, 28 September 2026
We wrote this piece in August. A month on, some of it has moved. Here's where things stand now.
El Niño has got stronger. NOAA's September update puts the chance of a very strong event this autumn and winter at over 90%, and gives a 75% chance that October to December will be stronger than any El Niño since records began in 1950. The World Meteorological Organization expects it to peak towards the end of this year, with knock-on effects running well into 2027.
Brazil's harvest is in. The rain that was slowing pickers in July eased off, and by late September Brazil's crop agency, Conab, reported 99% of the crop harvested. It's a record year for Brazil.
The flowering went the other way from what we feared. In August the worry was that El Niño would hold back Brazil's spring rains and delay flowering. Instead, unusual rain through Brazil's normally dry winter has brought flowering forward by around a month. That's broadly good news for next year's crop, with conditions attached. The flowers still need to set fruit, damp conditions raise the risk of fungal and bacterial disease, heat remains a risk, and 2027 is an "off" year in arabica's natural two-year cycle, when trees rest after a big crop.
The market has calmed down. With the Brazilian harvest landed and the flowering looking healthy, a lot of the fear has come out of prices. In late September arabica dipped below $2.75 per pound, its lowest since June and well under its summer highs.
Vietnam is now the one to watch. Vietnam's national forecasting centre expects rainfall across the Central Highlands, the heart of the country's robusta production, to run 20% to 40% below normal to the end of the year, with a very high risk of drought through the dry months of early 2027. That's the same pattern that hit Vietnamese robusta hard in 2015 to 2016.
Roland's central point stands. El Niño raises the risk, and the harvest decides the outcome. So far it's been kinder to Brazil than expected. For most origins, the real test is still the next harvest.
El Niño gets thrown around a lot, usually attached to a headline about weather going strange somewhere. It's rarer to hear what it is, or why a coffee roaster would care. So we sat down with Roland Glew, our Green Buyer, to work through it.
Start with the ocean
"El Niño and La Niña are variations in ocean temperature which drive fairly extreme weather," Roland says. "It's a cycle that applies and has always applied across the world. You have periods of relatively more neutral average weather, and years where you're having more extreme weather."
That's the whole thing in one sentence. The Pacific warms or cools, and the knock-on effects reach almost everywhere. The pattern shifts irregularly every two to seven years, disrupting normal wind and rainfall patterns across the tropics.
Where we are in the cycle
We're at the start of one. NOAA's Climate Prediction Center upgraded its El Niño Watch to an El Niño Advisory in June 2026, which means conditions have arrived.
"There's currently some predictions that it's likely we're seeing the start of a super El Niño at the moment, meaning a strong intensity El Niño," Roland says. "We've had these years in the past. It means relatively more extreme weather in the coming six to nine months, and that's likely to impact the whole globe. That's going to impact the UK, it's going to impact producing countries."
The forecasts back him up. NOAA's outlook has El Niño highly likely to continue into early 2027, with forecasters assigning a significant chance it reaches "very strong" territory, sometimes called a super El Niño. Australia's weather bureau has said it could become one of the strongest in seven decades. For the current numbers, NOAA updates its forecast monthly.
Why plants don't like it
"In general, those more extreme weather conditions aren't good for plants," Roland says. "Most plants are not going to do well in those kinds of extreme weathers that are outside the normal climate and life cycle for those plants. So we're likely to see harm to production."
Coffee is fussier than most. It needs rain at the right moment to flower in sync, and dry weather at the right moment to harvest and dry the cherry. Get the timing wrong in either direction and you lose yield, quality, or both. Without rain at the right point, flowers abort and fruit doesn't fill properly.
Brazil is the clearest example
"You're having issues at the moment with rain in Brazil, when normally now would be a dry period for the harvesting," Roland says. "Because it's raining, that's hard to harvest whilst it's raining."
On paper, 2026 should be a big Brazilian year. The USDA forecast a record 2026/27 crop of 71.9 million bags, up 14% on the year before. Picking it was another matter. By mid-July the harvest was 64% complete, behind the previous year's 77% and the five-year average of 70%.
The bigger worry is what comes next. El Niño can delay Brazil's September and October rains, which is exactly when flowering happens. That wouldn't touch the crop being picked. It would hit the one after it.
Every region gets a different El Niño
El Niño moves weather around. Some places dry out, others flood.
Looking back at past events, it takes a strong one to put a real dent in coffee production, and when it has, the damage has concentrated in Vietnam and Indonesia. Drought hit Vietnamese robusta hard during the 2015 to 2016 event. Across Honduras, Guatemala, Costa Rica and Colombia, the Pacific-facing regions tend to get extended drought, while the Atlantic side of those countries gets too much rain, and so does Peru. East Africa often gets more rain than usual, which can help yields and also make drying harder and disease more likely.
Same event. A different problem in every region.
Stacking on top of climate change
"Those producing countries are already under lots of pressure from climate change in terms of less predictable harvests and less predictable rains," Roland says. "Really this is just stacking on top of the other existing pressures of climate change, and labour shortages, and lack of money to invest in farms to help them become more resilient to these things."
Resilience costs money. Shade trees, irrigation, soil work, replanting with hardier varietals: all of it takes investment years before it pays back. Farms that can afford it will ride this out better than farms that can't, and the gap between those two groups is where the real risk sits.
What the market thinks
Futures move on fear long before anyone counts a single bag.
"The commodity market, because it works on a futures system, its prices have gone pretty high," Roland says. "They're looking at this year and next year and into the next year's harvest even, and saying we think there's a good chance the volume produced will be less than what's needed. So they decided to put those futures prices up to factor that in."
You could watch it happening through 2026. Arabica hit a low in early June, then climbed almost 50% inside a month on harvest delays and El Niño worry, with warehouse stocks near multi-year lows amplifying every scare. No coffee had gone missing yet. The market was pricing in the possibility.
Futures and shelf prices run on different clocks. What changes now is planning: everyone along the chain, from the farm to us, is working to a wider range of outcomes than usual.
Nobody knows yet
Roland is careful here.
"El Niño and La Niña is a cycle that is not wholly predictable or consistent. Scientists now are better at predicting it and managing it and understanding it, but we're still talking percentages. We won't really know until next year whether some of these things start to play out, and if so, how severe they end up being."
What it means for your coffee
We're buying the way we always have. Long relationships, prices agreed with producers rather than set by a screen in New York, and a willingness to pay what a coffee is worth when a harvest goes against a farm. That costs more in a calm year. In a year like this one, it's the whole point.
Roland Glew is the Green Buyer for Ozone Coffee Roasters and the founder of Strategic Coffee Sourcing.