I just noticed that there is an error in the timegmt element data in the storm xml data. Looks like they are all off by +1 hour. You can verify by looking at the time on the forecast advisories linked under the date vs. what is reported in the xml file.
Ah. They aren't all wrong. Just the ones that fall in Daylight Time. Those that fall in Standard Time are correct. I suppose a Standard time adjustment was applied to all data.