I run Thunderbird with Lightning both on my desktop and laptop. Now, I had a bit of an oddity. I have two Google Calendars that I use in Thunderbird via Lighting and Provider for Google Calendar add-ons. On my desktop machine the times are correct, however on my laptop all the times are one hour earlier. I thought may be the time zone was wrong on the laptop, but it does show it is set to the Arizona time-zone. Also, when I view my calendars on the web, all the times are correct (even when viewed using the laptop). This leads me to believe is an issue with the Thunderbird on the laptop.

So I posted this issue on my Thunderbird Forum and Malcolm suggested I check the time zone settings in Thunderbird (Tools > Options… > Lightning > Timezone). It has been so long since I had first setup Lightning that I had forgotten about this setting. I check on the desktop and it was set to America/Phoenix. At that time, my laptop was buried on my desktop under bunch of papers. Had a chance to unearth the laptop last night and got into the settings. Well, what do you know; it was set to America/Los Angeles. So, after switching it over to America/Phoenix and restarting Thunderbird, everything was showing the correct times.