Currently the weather pattern dominating Central Europe is bringing unusually cold air over the continent, and early this morning regions in a number of countries were hit by ground surface frost.
Parts of Belgium, Luxemburg, Germany, Switzerland, Austria and the Czech Republic saw surface frost - even down to the lower elevations (Belgium is hardly a mountainous region).
German site Wetter24 twittered here a map depicting the frosty areas gripping this 10th of July, 2015. Also see map here.
Swiss meteorologist Jörg Kachelmann here writes and supplies a link showing a German video reporting conditions that the German Eifel region woke up to early this morning. At the 1:50 mark the video reports:
We saw fields that were snow-white. That on the tenth of July I have never seen before. My colleague Fabian had also never seen this before. It just looked wonderful. We just thought that indeed we are not in autumn or spring; we are actually in July. These pictures impressed us, and that we found this frost."
Comment: See also: Winter is coming: Earth approaching 'mini ice age' in 15 year, solar cycle study suggest