[tz] Issue with EST timezone

Paul Gilmartin PaulGBoulder at aim.com
Tue May 7 20:59:15 UTC 2019

On 2019-05-07, at 14:26:06, Guy Harris wrote:

> On May 7, 2019, at 12:29 PM, Matt Johnson  wrote:
>> I added the status column awhile back to encourage people to use the Area/Locality forms of names instead of the older ones.  I just added some additional notes to the ones Manjusri cited to suggest alternatives.
> It now also notes that EST, MST, and HST do *not* have DST, so they shouldn't be used as synonyms for "Eastern time", "Mountain time", or "Hawaii time" unless you're in a location that doesn't observe DST.  E.g., EST currently applies to Quintana Roo but not to, for example, any location in the US or Canada, and MST currently applies to most of Arizona but not the rest of the Mountain time zone (HST currently applies to the Hawaii time zone).
Note, just to confuse things, by act of Congress, in the U.S.
Daylight Saving time *is* Standard Time:

 Sec. 260a. Advancement of time or changeover dates
    Duration of period; State exemption
    During the period commencing at 2 o'clock antemeridian on the
    first Sunday of April of each year and ending at 2 o'clock
    antemeridian on the last Sunday of October of each year, the
    standard time of each zone established by sections 261 to 264
    of this title, as modified by section 265 of this title, shall
    be advanced one hour and such time as so advanced shall for
    the purposes of such sections 261 to 264, as so modified, be
    the standard time ...

No mention or legal definition of "Daylight Saving".

That travesty impelled WWV to cease reporting "Eastern Standard
Time" and switch to reporting UTC.

-- gil

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