Everyone these days, it seems, deserves a day or two in the south of France. Weather Eye is no exception. Last weekend, purely in the interests of meteorology, I drove from Darmstadt down to Nice and returned without availing of any hospitality from friends, but what a wealth of weather was encountered on the way.
Driving down the Rhone valley, one could see first-hand the sharp escarpments that channel the dreaded Mistral towards the Mediterranean. I was told that in the vicinity of Marseilles the Mistral, that cold, fierce, winter wind, is exactly as portrayed in its fearsome reputation, but was surprised to hear that in Cannes and Nice it hardly bothers them at all. To do so, as they rightly pointed out, it would have to turn left and blow along the coast, and naturally enough, it very rarely does.
The Riviera, as you drive towards Monaco, is everything the picture postcards say, except that they do not show the noisy crowds, and the awesome August traffic that makes Dublin's problems seem not so very bad at all. But the real treat was driving north to Switzerland through the Great St Bernard Pass.
As befits a proper meteorologist, my car has a display to show the outside temperature, and climbing towards the Alps it was interesting to see the temperature fall gradually at a rate not too different from what weatherpeople call the "dry adiabatic lapse rate", or 3C per 1,000 feet.
It was also noticeable, as our altitude increased, that the sky was a much deeper shade of blue than usual. Indeed it was almost navy blue, the darker colour a consequence of the fact that there was less of the atmosphere above, and therefore less scattering of the sunlight by the molecules of air. This effect, taken to its extreme, would render the sky jet black if one were high enough to be outside the atmosphere entirely.
At 7,500 feet above sea level, at the Great St Bernard Pass, the Fohn effect was much in evidence with a light northerly breeze. Near the top on the Italian side it was crystal-clear at 12 C, but the northern, windward side of the pass had a shroud of cloud for the first few hundred feet of the descent, and the temperature dropped immediately to 10 degrees.
And thence down to sit on the lakeside at Montreux and see a perfect corona, on a moon that was almost full, reflected in the gently rippling waters of Lake Geneva. Bliss it was in that dawn to be alive; to have been young would have been very heaven.