A few days ago Kim and I went by Target, where we were mystified by an ice formation on the pharmacy sign outside. There was a long icicle—more than three feet, we estimated, and perhaps close to four—curving out from the middle of the sign. It was more or less perpendicular to the wall.   There were some smaller icicles attached to it, pointing in the same direction.

 

Viewed from the front, one could see that the ice was also very thin (a few inches across at its base, but only an inch thick in its other dimension, forming a very flat oval "footprint.")

 

We tried to get a photo, but it was dark and all we had was Kim's Blackberry, so the picture was poor.

 

I was back again the next day and took better photos, although the ice was broken and didn't protrude as far.

 

This presented several mysteries, all tied to how such a formation could be created.  Most obviously, how could the pointed icicle be sticking out from the wall?  It was slightly curved downward, like it had bent or formed with a polite nod to gravity, but it was convincingly horizontal.

 

Another mystery was how that much water got there in the first place. There would have to be a lot of snow on top of that sign to create that ice formation, it seemed to me; and why would it all go right to the middle of the sign?

 

I was there again yesterday, after more snow, and solved at least part of the mystery.  It turns out that the wind really whips the snow off of the store's roof, and it all collects atop the pharmacy sign.

 

As for how the icicle became perpendicular to the wall, I have three theories:

 

1) There is an air vent inside the sign to cool the lights, and it blows melted snow outward where it reforms into a jutting icicle; or,

 

2) The icicles form against the sides of the letters (in this case, the M) and then break loose and are twisted outward by the weight of the snow slowly melting, flowing, compacting, and refreezing close to the wall.

 

The second explanation seems most likely, even though I have a hard time visualizing the mechanics involved.

 

Kim and I both thought it was really bizarre, but I told her it was just as bizarre that I was spending so much time puzzling over it.