April 2026 was the third driest April in 35 years in Belgium according to figures from the Royal Meteorological Institute, the RMI. In Ukkel (Brussels), barely 9.1 millimetres of rainfall fell. That’s less than a fifth of what we would normally expect. We also had 40 per cent more sunshine than the long-term average. We are now facing a significant rainfall deficit.
April is generally a month with little rainfall. According to the long-term average, 46.7 millimetres of rainfall is normally recorded. Last April was particularly dry, with just 7 days of rainfall instead of 13, and around four-fifths less rainfall than usual.
The rainfall map compiled by the RMI leaves little to the imagination. The map of Belgium is coloured dark brown. Virtually all regions received much less rain than usual, with the worst affected areas being the north of West Flanders (where only 10 per cent of the normal amount fell) and the region around Dendermonde (East Flanders).
The map above shows how much rainfall was recorded compared to the long-term average (1991–2020). Many areas have not even reached 15 to 20 per cent of the normal level.
The darker the colour of a location, the drier it is. However, this is not a record: in April 2007, there was no rainfall at all in Ukkel for an entire month. In April 1996, there was barely 6 millimetres. In 2001, on the other hand, there was 134 millimetres of rainfall.
“We currently have a rainfall deficit of 50 millimetres,” hydrologist Patrick Willems (KU Leuven) told VRT NEWS. “This is due to low rainfall combined with high evaporation, and the fact that there was a lot of wind, often a dry easterly wind. The rainfall deficit is already quite high for this time of year.”
What are the implications?
For the time being, the drought is not causing any major problems, but there needs to be significantly more rainfall in May. This is because water levels in rivers and watercourses are falling rapidly, and groundwater levels are also continuing to decline. We will have a clearer picture of this in a week’s time.
‘At the moment, we don’t need to worry too much. We’re still on code green, but if it stays dry for a few more weeks, that could change to code yellow,’ says Willems. In that case, we can expect measures to be taken. It’s forecast to rain this coming weekend, but it remains to be seen whether there will be any sustained rainfall after that.
The rain is welcome news for farmers too, says spokesperson Tessa De Prins. ‘There aren’t any problems at the moment, but crops with fine seeds, such as carrots and spinach, need a good soaking to germinate. So rain is certainly welcome.’
Abundant sunshine
We were able to enjoy the sun much more often than usual in April. In the end, the total in Ukkel stood at 241 hours of sunshine, far more than the average of 171 hours.
It was also warmer than average. The average temperature for the whole month was 11.7 degrees Celsius, compared to the usual 10.4 degrees. The average maximum temperature was 17.1 degrees, compared to the usual 15 degrees.
The fact that it was warmer than average is clearly shown in the graph from the RMI below, which indicates the daily deviation. Red bars indicate a warmer-than-average day, blue bars a cooler-than-average day.