Temperatures in Belgium's main measuring station in Ukkel climbed above 25 degrees Celsius this morning, giving the heatwave an official status. In Belgium, we need five consecutive summer days (with 25 Celsius or more) of which at least three are tropical days (30 Celsius or more) to have a heatwave.
This heatwave started last Tuesday with a maximum of 27.6 Celsius in Ukkel. The past three days we had 30.6, 31.4 and 32.1 as maximum temperatures, David Dehenauw of the Belgian Met Office KMI tweeted.
And the coming days?
The maximum temperature today may be even higher. Sunday will also be a hot day, and humidity will increase as well to create more discomfort. This marks the first start of an upcoming change. Showers or thunderstorms may occur later on Sunday and also on Monday, after which the temperature will stay below 30.
To which extent is the world getting hotter?
The fact that we have an official heatwave or not, needs to be put into perspective. It is better to count the number of summer days or tropical days in a year to measure the greenhouse effect. In the seventies we had 1.4 tropical days in Ukkel each year on average. This number has seen a fourfold rise, climbing to 5.6 now.