That is only if you are using a Roman Calendar, not
the Julian Calendar...Here is Wiki's definition of
"The Ides of March" and the link:

[link to en.wikipedia.org]

The Ides of March (Latin: Idus Martii or Idus Martiae) is a day on the Roman calendar that corresponds to 15 March. It was marked by several religious observances, and became notorious as the date of the assassination of Julius Caesar in 44 BC. The death of Caesar made the Ides of March a turning point in Roman history, as one of the events that marked the transition from the historical period known as the Roman Republic to the Roman Empire.

The Romans did not number days of a month sequentially from the first through the last day. Instead, they counted back from three fixed points of the month: the Nones (5th or 7th, depending on the length of the month), the Ides (13th or 15th), and the Kalends (1st) of the following month. The Ides occurred near the midpoint, on the 13th for most months, but on the 15th for March, May, July, and October. The Ides were supposed to be determined by the full moon, reflecting the lunar origin of the Roman calendar. On the earliest calendar, the Ides of March would have been the first full moon of the new year

But you are correct about the "full-moon" connection. It
was only during the Roman empire, however. But It could
easily be argued either way.

So...technically, we should be watching from the
4th of March thru the 16th or 17th of March for an
"Ides" warning. It's really just splitting hairs when
you are talking about a potential danger like the
CERN experiment. Take some nice pictures of Switzerland
cause it might not ALWAYS look the way it does now.
Guess we'll see won't we!

O'sCookie