I am still puzzling with what to do if you move (relocate) a station.
I searched the basic WMO regulatory material, but didn't find an answer or
guidelines although I thought we solved it already.
So, we have to propose some guidance to WMO to be inserted in e.g. the Man.
WIGOS. (WMO-No. 1160) or Guide to the WIGOS (WMO-No. 1165). This Manual gives clear statements on issuing stations
identifiers and the WSI format (will be discussed during next WMO Congress (see Cg-18/Doc. 6.1(1) on http://meetings.wmo.int/cg-18/English/Forms/AllItems.aspx)
We (in the NL) had comparable issues starting in the '90s.
Because of urbanization we sometimes have to move a station. (I recommend not
to simply move a station to a nearby location, but to do research first on how
to improve your whole network design by finding a new and better location).
Therefore we have developed a policy on when to change an Id, or not, in case
of a movement.
The first and major criterion is 'representativety' in the sense
that if you expect a 'break' in the climate records you should always change Id
and name. Relevant is that Station Id and Station Name is coupled. In
principle, if you change the name, then should change the number too, and vice
versa, but that's not always easy to realize (think to large cities or large
airports, > 10 km). The problem however is that you should first perform
parallel measurements (as required by WMO, for 2 years) to know if a significant break may
be expected (so start with a 'test' Id and Name).
Then we follow 4 rules:
 if the new station is in the same community (or township)
[the smallest political community with its own local council] than Id and Name
 if the new station is in the same community (or township),
but has a significant different representativity than change Id only (so name
is unchanged; to be avoided, but not always possible)
 if the new station is a neighboring community (or township)
but there will not be a change in representativity (or a break in the
climate records) than Id and Name are unchanged (to be avoided, but not
always possible and recommended by the climate community).
 if the new station is in a another community (or township)
and there will be a change in represenativity (or a break in the climate
records expected) than Id and Name are changed (i.e. all other cases).
I experienced that in fact only rule  was used, so we always
changed Id and Name.
In fact I am in principle only happy with rule  and , i.e. to maintain the link ID-Name, or change both.
Apart from this, two issues remain:
[a] what to do with e.g. windmasts, located relatively far from
an AWS, but representative for the area in which the AWS is located (far from
AWS because at the AWS the wind is disturbed, or in case you like to do
measurements on two wind locations to get a better idea about the wind at that
area like in mountainous areas).
[b] what to do with 'twin stations'. E.g. Upper air station De
Bilt and nearby Upper Air Station Cabauw are 'twin stations' for GRUAN (De Bilt
provides Radio Sonde data, Cabauw the rest, like Windprofiler data).
-Jitze van der Meulen