Cumulus Support

If Cumulus is running (and as you say, continues to run for an hour after the change), it doesn't matter when the console clock changes, as the console clock is only used for logger data. If the console doesn't automatically adjust for you, the safest solution is to manually adjust it as soon as possible after the change, leaving Cumulus running.

I can't remember what happens to logger data when DST ends, whether two entries with the same timestamp get downloaded, or whether they are effectively superseded. I imagine that the logger just creates two sets of entries with the same timestamps, but I don't know what it then supplies when asked for them. And of course the Davis DLL also has a hand in things just to add to the complication; so the answer to what the console does may not be the full story. But the only full and safe solution to the DST issue is to always run the station and PC on standard time.

mcrossley wrote:Doesn't the console automatically switch DST (for US, Europe, and most of Austrailia) ?

I don't think it gets it right for some regions, so they have to turn off automatic changing.

@ Mark
My Vantage Vue Console manual (and it seems to be the only manual for everyone - i.e. not a New Zealand specific manual) says,

Weather stations located outside the United States, Canada, and Europe, or in areas that do not observe daylight saving time should use the MANUAL setting.

So if not in the area where daylight saving is supported by Davis you change AUTO to MANUAL and then you are supposed to go into setup mode and switch between Daylight Saving on and off at the appropriate times. It is much simpler to restart Cumulus.

@ Steve
I don't think it is all that practical to run a PC in standard time all the time unless it is entirely dedicated to the purpose but it is an interesting option which I will think about.

While we don't have daylight saving here in Queensland, Australia, I have noticed that daylight saving or summer time does seem to change on different dates around the world. There does not seem to be a set standard date for it to begin & end. There has been quite a few changes of these dates here in Australian states that use daylight saving over the years. This makes it impossible to have an automatic change over date that will work everywhere.
I think Davis stations are set to change on the USA dates if automatic change over is selected, otherwise using manual change over is probably the best way to go.

There are libraries for programmers with this data included, so I don't think it is impractical but is probably more effort than one would want expend to incorporate it into a system such as Cumulus.