The 'new code' came in in the early nineties. I was an assistant at Rheidhalen at the time and plotting charts. On January 1st there was a mixture of old and new being used. The old was quicker to hand plot. with the new code you had to remember to check if there was any present weather after plotting the vis and to leave enough room for weather symbol.

Plotting Tephis used to be tricky at times when new radio sondes came as the messages had so many special points.

The good old days!