Saskia Messager, Nov 14^th 2011

In the Netherlands today bleu sky and no persistant contrails

Webcam KNMI -> No persistant contrails

http://www.knmi.nl/webcam/

Radiosonde

http://weather.uwyo.edu/cgi-bin/sounding?region=europe&TYPE=TEXT:LIST&YEAR=2011&MONTH=11&FROM=1412&TO=1412&STNM=06260

Between approx. 10000 and 12000 meters altitude:

Temp: -64°C< T < -53°C

Relative humidity: 12%< rH< 32%

Photo sky De Bilt (camera is dirty but sky crystal clear)

In France today bleu sky and tremendous amount of persistant contrails

Webcam Bordeaux

Webcams météo - Meteo Bordeaux - Le premier site météo pour Bordeaux et le Nord de l'Aquitaine

Radiosonde Bordeaux

http://weather.uwyo.edu/cgi-bin/sounding?region=europe&TYPE=TEXT:LIST&YEAR=2011&MONTH=11&FROM=1412&TO=1412&STNM=07510

Between approx. 10000 and 12000 meters altitude:

Temp: -62°C< T < -51°C

Relative humidity: 20%< rH< 44%

Photo sky Bordeaux

Photo sky Paris region (Bleu sky + persistant contrails + pollution )

The question is why, with those unfavourable atmospheric conditions for persistant contrails (low relative humidity) today in France we still had very persistant contrails ??