Pac/Mtn border at Winterhaven California)

Alois Treindl alois at
Mon Sep 12 11:54:58 UTC 2011

I have researched in newspaper archives, and found an article in the 
paper 'The Mountain Democrat Times' of 1968 March 28, which confirms 
that the whole area on the Yuma AZ side of the Colorado River but 
belonging to California followed even then Arizona time, i.e. MST 
without observing DST.

It mentions the post office in Bard, CA as an example, and probably it 
includes the populated places Winterhaven, Ross Corner and Bard.

Before 1968 I found no source. But probably we can assume that this 
habit has been permanent. The simplest is to include this area with 
Arizona, for timezone purposes.

On 07.04.11 06:45, Steve Jones wrote:

>> CA: Winterhaven California, in deference to its proximity to Yuma AZ,
>> observes Mountain Standard Time year round. This means that (like AZ)
>> Winterhaven does not observe Daylight Saving time. So this puts
>> Winterhaven ahead of California by one hour (in sync with Arizona)
>> during Standard time - in the Fall and Winter. And in sync with both
>> CA and AZ during Spring and Summer (Daylight Saving time). The
>> dividing line of this observed boundary is locally considered to be
>> the "All American Canal".

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