Starship Asterisk*

Go to http://www.wunderground.com/history/air ... story.html for the weather on June 20, 2004. Snow! I think not. Ice! Not unless some liquid nitrogen was dumped (shades of the terminator).
Plus I think that Professor Walter Lewin has the only correct answer to date.

Very dry for MA in June as I recall.

However, a construction site could have a lot of recently turned, moist earth. I cannot see from the picture quite what the background may have been composed of.

I wish I remembered the physics of a Lunenberg lens used (many years ago in my direct experience), but probably just as effective a radar reflector. as it was then.

A fun puzzle! /Mac