Not sure if this is a new facility (on this site) or it's been hidden,
but the following looks quite useful:

http://www2.wetter3.de/Archiv/archiv_dwd.html

Archive at *6* hourly intervals, with plotted obs, since 3rd December,
2003.

You can also step forward/back, either at default 6-hour steps, or by
selecting '1 Tages- Schritt', in daily time-steps.

Martin.


--
FAQ & Glossary for uk.sci.weather at:-
http://homepage.ntlworld.com/booty.weather/uswfaqfr.htm
[ with Search facility ]
and
http://booty.org.uk/booty.weather/metindex.htm