Re: Can electricitiy arc between droplets of water?

An electric current can pass through most materials. Basically the only difference is the voltage required. Arcing is different to having a current flow through a liquid or solid.

Arcing requires the gas to "breakdown". That is the normally good insulating properties of the gas are overcome, the gas ionises and the conductivity of the gas becomes quite good. Lightning obviously can do this to air.
http://en.wikipedia.org/wiki/High_voltage
http://www.scienceclarified.com/Di-El/Electric-Arc.html

Drinking water is a better conductor of electricity than air is (below its breakdown voltage).
http://en.wikipedia.org/wiki/Electrical_conduction
http://www.lenntech.com/water-conductivity.htm
The path a current takes depends on the electrical conductivity of the materials.

Now if lightning hits your house and you have metal plumbing chances are that a sizable charge will flow through your plumbing. At the shower head you may then have a high voltage, quite possibly high enough to arc through the air.

Let's say you are standing in the shower. Your head is near the shower outlet which has a high voltage on it from the house being struck by lightning, and there are droplets of water between your head and the shower. It could well be that an arc could form between your head and the shower outlet directly, or maybe the arc will flow to droplet, then arc again. It is very hard to say just exactly what path the arc would take, however what is definitely known is that if there is enough potential difference to form a lightning bolt across many thousands of feet from sky to ground chances are if you get in the way of that current a few inches between your head and shower outlet are unlikely to be enough of an insulator to prevent an arc continuing to ground.

The water droplets between your head and the shower will only make that electrical path easier.

Now having said that we need to look at a few other variables. It may well be that there are better electrical paths to the ground than through the plumbing and your head/body. This would be especially true if your house is well grounded (so a good low resistance path exists through thick metals to the ground) or if your plumbing is plastic.

Finally to answer your opening question a bit more pedantically. Can electricity arc between water droplets? The answer to this is most certainly yes. If you have two droplets of water and one has a very high voltage on it and the other doesn't it is possible if that potential difference is high enough to breakdown the air in between and arc between the two droplets.

It is a less certain whether a lightning bolt from a shower outlet would arc between water droplets or just form a longer arc (through ionised air) to your head, or in fact do both. I would also assume large currents through small droplets would cause them to heat up and boil.
http://amos.indiana.edu/library/scripts/shower.html
http://articles.directorym.net/BEYOND_THE_BASICS_Lightning_Strike_Injuries-a878608.html
http://science.howstuffworks.com/struck-by-lightning.htm/printable