Yesterday morning was warm and humid in the valley of the Rhine. The roller-bladers, with their floppy, knee-length shorts and shoulder bags, were zapping randomly along the city footpaths. In the suburbs, the mothers and their toddlers had ice cubes in their apfelsaft upon their patios.
In the offices of Darmstadt, shirts merged into a kaleidoscope of pastel shades above the desks. A discarded jacket adorned the back of every swivel chair.
It was the first real day of summer and not a single cloud obscured the smallest corner of the sky.
But by 4 p.m. it clouded over. In 15 minutes, the afternoon was darker than any moonlit night. The humidity became unbearably oppressive; window by window the lights came on around the city and a few drops fell.
After a flash or two of lightning, followed almost immediately by several loud, threatening, almost evil, peals of thunder, the rain came down in what could only be described as sheets.
Floods appeared instantly on the roads as if a vast, celestial bucket was being emptied on the city. And the trees began to stir - and then the wind.
The squall was fiercer and angrier than any of the winter gales I remember from my youth in Co Kerry. The rainswept trees, laden with summer foliage, bent first together to the left, trying their best to reach the protective horizontal.
Then, after several minutes, the wind direction changed without abating - and the trees were bent the opposite way. I have no means of confirmation but the wind strength must have been significantly in excess of 100 m.p.h.
Meanwhile, there was chaos on the streets. The traffic stopped, the people scattered. Fire alarms, set off by lightning, screamed in competing demand for immediate attention. The jangle of sirens added to the din as fire engines, weaving in and out of stationary cars, did their best to answer as many of the calls they could.
And then, 30 minutes after it began, it was all over.
The wind was calm, the rain had stopped, the sky had cleared. And it was, once again, a warm and pleasant summer afternoon in Germany.
Only the pools of water in the streets were a reminder of the mayhem, along with the large branches of the weaker trees which were unable to withstand the onslaught.
I have often wondered why we call a thunderstorm a thunderstorm. My experience suggested that the less dramatic "thunder shower" was more appropriate. But now I have seen a real thunderstorm and I can confirm that it is fully worthy of the name.