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Short Weather Cypher Decrypting Procedure




M3-UKW = B


M3-UKW = C



Decrypting a Kriegsmarine 3-rotor Short Weather Cypher Message


Note:  The Kriegsmarine 3-rotor and temporarily modified 4-rotor Enigma machines were used by U-boats and converted fishing trawlers to relay

weather information from the north and west, the directions from which Germany's weather came, to B.d.U. (U-boat Headquarters). These "floating weather observers" were critical to both German strategic (long-range) and tactical (short-range) battle planning.

To view this entire procedure, please click on "The Short Weather Cypher Decrypting Procedure" bullet below.


1.  Print-out a paper copy of all of these documents by clicking on the links:

Note: We will select sample values from the tables to use for our example U-boat in this procedure.  To send your own Enigma-encrypted

Short Weather Cypher message to a friend, you may, of course, choose any table settings or values you wish.

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