On 27 January 2008, a strong northwesterly flow formed well-developed, low-level waves to the lee of the Ore mountains (also known as Krušné hory or Erzgebirge mountains, on the border between northwest part of the Czech Republic and eastern part of Germany.
04 May 2021
26 January 2008
by Martin Setvak (CHMI)
As the loops of MSG images (below) show, the waves persisted for most of the day, hardly changing their position and extent. In the parts of waves with descending flow the clouds dissipate, forming cloud-free bands. In contrast, the clouds form and persist in those parts of the waves where the air is ascending.
More details can be seen in the images from polar orbiting satellites, like MODIS images (see Aqua MODIS band 1 image at 11:50 UTC (250 meter resolution) and the corresponding RGB composite (500 meter resolution, bands 01-04-03)), and AVHRR images (see NOAA-17 image below and NOAA-15 image at 15:17 UTC (night microphysics RGB composite)).
The animations given under 'see also' (e.g. Airmass and Snow RGB products) show that similar mountain waves formed on 27–28 January over most of central Europe — also to the lee of the Small Carpathian Mts. (spreading over Slovakia and Hungary) and in the lee of the Alps and Dinaric Mountains. In addition, stau cloudiness north of the Alps and orographic Cirrus related to high-level waves south of the Alps can be observed (the latter best in the Airmass RGB , 00:00–23:45 UTC).
NOAA-17 AVHRR Composite
NOAA-17, 27 January 2008, 09:57 UTC
RGB Composite VIS0.6, VIS0.8, IR11.0
Animation Airmass RGB Composite (00:00–23:45 UTC)
Animation RGB Composite VIS0.8, NIR1.6, IR3.9r (06:30–15:30 UTC)
Animation RGB Composite HRV, HRV, IR10.8 (28 January, 07:00–12:15 UTC)
Aqua MODIS band 1 image at 11:50 UTC (250 meter resolution)
Aqua MODIS true-colour RGB composite at 11:50 UTC (500 meter resolution)
NOAA-15 AVHRR night microphys. RGB composite at 15:17 UTC (1.1 km resolution)
Wave clouds over the Massif Central, France (6 February 2006)
Detection of mountain waves over Spain in the WV7.3 channel of MSG (28 December 2004)
Meteosat-9 HRV Image
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