RE: DOT issues final ruling on Indiana time zones
Probably I'm missing something, but why "2:00 AM CST to 1:00 AM CDT". In the spring, 1:59:59 is followed 1 second later by 3:00:00 CDT. I don't understand why you have it in the other direction. ++PLS -----Original Message----- From: tz-request@elsie.nci.nih.gov [mailto:tz-request@elsie.nci.nih.gov] On Behalf Of Deborah Goldsmith Sent: Wednesday, January 18, 2006 7:12 PM To: tz@lecserver.nci.nih.gov Subject: Re: DOT issues final ruling on Indiana time zones You're right, that should have been "fall back from 2:00 AM EST to 1:00 AM CST, then again from 2:00 AM CST to 1:00 AM CDT". Sorry about that. From the final DOT ruling (posted earlier) it appears as though that is in fact the correct behavior, too, as odd as it is. Deborah On Jan 18, 2006, at 5:38 PM, Paul Schauble wrote:
Since this is in the spring, shouldn't that last change be from 2AM CST to 3AM CDT?
++PLS
-----Original Message----- From: tz-request@elsie.nci.nih.gov [mailto:tz- request@elsie.nci.nih.gov] On Behalf Of Deborah Goldsmith Sent: Wednesday, January 18, 2006 5:38 PM To: tz@lecserver.nci.nih.gov Subject: DOT issues final ruling on Indiana time zones
<snip> assuming I'm interpreting everything correctly. The DOT doesn't specify whether Starke county switch to Central Time at the appropriate time for its old or new time zone, but I'm assuming the old here. That leads to it falling back from 2:00AM EST to 1:00AM CST, and then again from 2:00AM CST to 1:00AM CST. If that makes people nervous, then the transition would need to be at 3:00 AM.
Deborah Goldsmith Internationalization, Unicode liaison Apple Computer, Inc. goldsmit@apple.com
You're right, I had it backwards, but it's not quite the way you're putting it either. What I should have said is that in America/Indiana/ Knox, 1:59:59 EST is followed immediately by 2:00:00 CDT. The rules I posted should be correct, though. Deborah On Jan 19, 2006, at 1:57 PM, Paul Schauble wrote:
Probably I'm missing something, but why "2:00 AM CST to 1:00 AM CDT". In the spring, 1:59:59 is followed 1 second later by 3:00:00 CDT. I don't understand why you have it in the other direction.
++PLS
-----Original Message----- From: tz-request@elsie.nci.nih.gov [mailto:tz- request@elsie.nci.nih.gov] On Behalf Of Deborah Goldsmith Sent: Wednesday, January 18, 2006 7:12 PM To: tz@lecserver.nci.nih.gov Subject: Re: DOT issues final ruling on Indiana time zones
You're right, that should have been "fall back from 2:00 AM EST to 1:00 AM CST, then again from 2:00 AM CST to 1:00 AM CDT". Sorry about that.
From the final DOT ruling (posted earlier) it appears as though that is in fact the correct behavior, too, as odd as it is.
Deborah
On Jan 18, 2006, at 5:38 PM, Paul Schauble wrote:
Since this is in the spring, shouldn't that last change be from 2AM CST to 3AM CDT?
++PLS
-----Original Message----- From: tz-request@elsie.nci.nih.gov [mailto:tz- request@elsie.nci.nih.gov] On Behalf Of Deborah Goldsmith Sent: Wednesday, January 18, 2006 5:38 PM To: tz@lecserver.nci.nih.gov Subject: DOT issues final ruling on Indiana time zones
<snip> assuming I'm interpreting everything correctly. The DOT doesn't specify whether Starke county switch to Central Time at the appropriate time for its old or new time zone, but I'm assuming the old here. That leads to it falling back from 2:00AM EST to 1:00AM CST, and then again from 2:00AM CST to 1:00AM CST. If that makes people nervous, then the transition would need to be at 3:00 AM.
Deborah Goldsmith Internationalization, Unicode liaison Apple Computer, Inc. goldsmit@apple.com
Sorry for the spam; I swear this is the last message. If I still have it wrong, I'll let someone else straighten it out. :-) In America/Indiana/Knox, on April 2, 2006: 1:59:59 EST is followed by 1:00:00 CST (because this location switches to Central Time at that moment, and it's Standard Time in that zone) 1:59:59 CST is followed by 3:00:00 CDT (the normal DST transition) It doesn't happen in one step; if it went from 1:59:59 to 3:00:00, it would be on EDT, not CDT. If it went from 1:59:59 to 2:00:00, then Knox would be on CDT an hour before the rest of its time zone. Now, that actually makes sense (clocks wouldn't have to change), but it's not what the DOT ruling says. It says "Starke county moves from ET to CT at the moment of the DST transition in the ET zone." Deborah Goldsmith Internationalization, Unicode liaison Apple Computer, Inc. goldsmit@apple.com
I think your last interpretation finally got it right, this is what the DOT says. But I think they goofed up something when they wrote the DOT. The effect is that Indiana goes from GMT-5 to GMT-6 during one hour, and then to GMT-5 again one hour later??! In reality, I'm sure what they wanted to do is to keep Indiana on GMT-5 and on Eastern time until Central timezone shifts to Daylight Saving, and then define that point in time to be the shift in timezone. Then nobody in Indiana has to change wall clock in spring, until autumn when CDT shifts back to CST. I'll bet you no matter what official documents have been issued they won't shift the wall clock one hour behind just to shift it one hour ahead, an hour later. In effect at 2:59:59 EST they will shift to 3:00:00 CDT without any wall clock change. So the DOT text should have read "The effective *time* of this rule is 2:00 a.m. CST Sunday, April 2, 2006, which is the changeover *time* from Central Standard Time to Central Daylight Saving Time" ... or they could have used "3:00 a.m. EST" to the same effect. The rule should in tz-database format would then be -5:00 - EST 2006 Apr 2 3:00 -6:00 US C%sT In short, Indiana is on Eastern time until 3:00, and from then they are on Central (Daylight) time. By the way I don't think the time 2:00:00 CDT exists for that date (from an earlier mail), even for any place in the world - but that is maybe more of a philosophical problem. 2:00:00 CST and 3:00:00 CDT would exist (at least the latter) because they are in fact, the same. Jesper Nørgaard Welen -----Original Message----- From: Deborah Goldsmith [mailto:goldsmit@apple.com] Sent: Thursday, January 19, 2006 16:33 To: tz@lecserver.nci.nih.gov Subject: Re: DOT issues final ruling on Indiana time zones Sorry for the spam; I swear this is the last message. If I still have it wrong, I'll let someone else straighten it out. :-) In America/Indiana/Knox, on April 2, 2006: 1:59:59 EST is followed by 1:00:00 CST (because this location switches to Central Time at that moment, and it's Standard Time in that zone) 1:59:59 CST is followed by 3:00:00 CDT (the normal DST transition) It doesn't happen in one step; if it went from 1:59:59 to 3:00:00, it would be on EDT, not CDT. If it went from 1:59:59 to 2:00:00, then Knox would be on CDT an hour before the rest of its time zone. Now, that actually makes sense (clocks wouldn't have to change), but it's not what the DOT ruling says. It says "Starke county moves from ET to CT at the moment of the DST transition in the ET zone." Deborah Goldsmith Internationalization, Unicode liaison Apple Computer, Inc. goldsmit@apple.com
Deborah Goldsmith <goldsmit@apple.com> writes:
In America/Indiana/Knox, on April 2, 2006:
1:59:59 EST is followed by 1:00:00 CST (because this location switches to Central Time at that moment, and it's Standard Time in that zone) 1:59:59 CST is followed by 3:00:00 CDT (the normal DST transition)
That may be what the letter of the regulation says (I can't get docket OST-2005-22114 from http://dms.dot.gov right now) but if so, the regulation is obviously in error. The intent is that 01:59:59 EST be followed by 02:00:00 CDT. Nobody is going to change their clocks twice in the same morning. Hence on April 2 there will be an extremely unusual one-hour period during which there will be five (instead of the usual four) time zones in the lower 48 states: PST (-0800), MST (-0700), CST (-0600), CDT (-0500, in a few counties of Indiana), and EDT (-0400). I'll draft a proposed change along those lines. It's a bit more complicated than the patch you sent, because America/Indiana/Indianapolis needs to split into two zones. Daviess, Dubois, Knox, Martin, Perry, Pike, and Pulaski counties, which are currently in the America/Indiana/Indianapolis zone, need their own zone now that they are moving to central time which means they now have a new unique time zone history. Starke county already has its own zone America/Indiana/Knox, and that entire zone will move to central time, so it does not need to split. I think the biggest city in the new zone is Vincennes, so the new zone should be called America/Indiana/Vincennes.
On Jan 19, 2006, at 9:29 PM, Paul Eggert wrote:
Hence on April 2 there will be an extremely unusual one-hour period during which there will be five (instead of the usual four) time zones in the lower 48 states: PST (-0800), MST (-0700), CST (-0600), CDT (-0500, in a few counties of Indiana), and EDT (-0400).
I'll draft a proposed change along those lines.
Would this work for America/Indiana/Knox (note especially the -5:00 on the second-to-last line)? Zone America/Indiana/Knox -5:46:30 - LMT 1883 Nov 18 12:13:30 -6:00 US C%sT 1947 -6:00 Starke C%sT 1962 Apr 29 2:00 -5:00 - EST 1963 Oct 27 2:00 -6:00 US C%sT 1991 Oct 27 2:00 -5:00 - EST 2006 Apr 2 2:00 -5:00 - CDT 2006 Apr 2 3:00 -6:00 US C%sT
It's a bit more complicated than the patch you sent, because America/Indiana/Indianapolis needs to split into two zones.
I agree, but I have to submit something today. I can't wait any more. Deborah
Date: Thu, 19 Jan 2006 14:32:30 -0800 From: Deborah Goldsmith <goldsmit@apple.com> Message-ID: <B92731EB-E56F-4FC4-8E03-A129956F3BEE@apple.com> | If it went from 1:59:59 to 2:00:00, then | Knox would be on CDT an hour before the rest of its time zone. Now, | that actually makes sense (clocks wouldn't have to change), but it's | not what the DOT ruling says. It says "Starke county moves from ET to | CT at the moment of the DST transition in the ET zone." I bet if asked, that's what they tell you they expect to happen, and I'd bet that in practice, no-one in that county changes their clocks, whatever the DOT ruling actually says if you treat it literally. If you want to remain in line with the time that people actually use I think the change in the tz files should simply have the time advance forward with no gaps or discontinuities for this particular transition, and the zone name change at any time that seems reaosnable (given that the zone name doesn't really matter to anything anyway - CST after all is the time in Adelaide, Australia, which is UTC+10:30, it is also the zone name in Adelaide in winter - UTC+09:30... kre
On 19 Jan 2006 at 14:04, Deborah Goldsmith wrote: [Much discussion omitted. DC.]
You're right, I had it backwards, but it's not quite the way you're putting it either. What I should have said is that in America/Indiana/ Knox, 1:59:59 EST is followed immediately by 2:00:00 CDT.
But CDT doesn't begin until 3:00:00 CDT. In some sense, 2:00:00 CDT doesn't exist. That is, what you're proposing is that America/Indiana/Knox begins observing CDT an hour earlier than the rest of the Central Time Zone. Maybe that's right. The ruling you posted should have been clearer, but that's not the fault of anyone here.
The rules I posted should be correct, though.
-- Dave Cantor Groton, CT 06340-3731 DCantor@shore.net
participants (6)
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Dave Cantor -
Deborah Goldsmith -
Jesper Norgaard Welen -
Paul Eggert -
Paul Schauble -
Robert Elz