On 2013-08-21 08:34:28 +0000, Metman2012 said:

On 20/08/2013 19:02, Paul wrote:
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!

Hmm, I thought that it was in the early 80s, but I'm not going to
argue, especially as I can't find any details via a Google search. I
left Heathrow in 81 and my memory is that the new code came in not long
after. I can still easily 'read' the old codes (thanks to plotting
charts for ten years!) but can only do it slowly on the 'new' code (no
longer using it daily, being at Bracknell in research). Can anyone
confirm the date?

Well, I am with you on this. I was observing in the early 1980s and I
have a memory of something big happening which involved the issue of
new Daily Registers. I assumed that was the change to the SYNOP code,
but it may have been something else.

Surely there must be someone in MO Archives who can make a quick check?
I thought the registers were stored indefinately.