Wednesday, March 21, 2007

Henrik, waiting to read if we flew no ? Well we didn't. I just had time to groundhandle my Niviuk Artik a while, to check the renewed lines. But couldn't fly it, some things told me it wasn't right. No need for a windmeter, sometimes your nose (depends on the size of course ...) tells you.

Temperature dropped suddenly, no wind, some rimples in the sea. Clouds were forming rapidly. And I enjoyed it. I loved watching the sky. I don't know if it is very clear on this photo, taken at take off. You can tell the hard and strong norhtwestern winds, were pushed back by the all of a sudden eastern strong winds. Where did they come from ? Seabreeze, that strong ? A bag of cold air over the sea (should be noticeable on the 500 hPa charts, but it isn't) ?
A wild convergence, very aggressive. Meteo is such a wonderful thing. And the more you read, learn about it, the more exciting, because in my opinion the knowledge and the trying to understand it never ends.
(I do sound pretty serious here, I think we need to fly soon ...)

We had some clouds that some british pilots never have seen before, and secretly I was happy they were interested. These clouds were Altocumulus Castellanus at one point. They look like the battlements of a medieval castle. Instability (not usable for us!), usually followed by thunderstornms later in the day. And indeed there is lightning over the sea now, 9 pm.
On height we had cold north-norhtwestern winds, and this very cold layer of air is coming in., sliding over the warmer air, over the castellanus clouds. Some bubbles of air, rise from the cloud deck (saturated adiabatic), and form these 'castellanus'.
Any heating up of the surface during the day will add, and feed the castellanus. (convection)
These castellanus clouds should be an alert to us, paragliding pilots, because they can easily develop into more dangerous clouds like first cumulus congestus, followed by cumulus nimbus.
More ? If you have these castellanus as we had this afternoon, you should know that the formation of these involved, involves vertical air movement, causing severe turbulence. So nothing for us, unless we are called 'Ewa' of course.
What a nose eh ?

Sorry, hope you read me tomorrow, this was very serious wasn't it ? Cheers.

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