The general words is "yes." Every EV can be charged in the rain, unless the owner's manual has specific warning about it. Before you do it check your manual or call the dear and ask.
"Absolutely, no worries, you will be fine. I turn my blue cap for the end of the charger so that it faces downward so when I cover it when the charge is done, it doesn't provide a source of water in the charger," writes a LEAF owner Dave in Nissan LEAF Owners Group.
Alan, another LEAF owner says "don't let the wall outlet end get too wet, though."
This is a good and important point about not letting the wall outlet to get too much wet. "Older outdoor outlets are not watertight if a cord is plugged in. If you plan to do a lot of trickle charging make sure the outlet is in a sheltered location or has a cover that keeps the rain off even with a cord plugged in. I wouldn't worry about it for occasional use. New covers are about $15 and install easily," writes Bill in the same group.
Here is another feedback from a Tesla owner from Chicago. "I live in Chicago and took delivery 12/24/2012. I live in a 3 unit condo building with gated parking in the back. The car is outdoors in the rain and snow connected to the UMC and a 240 volt 14-50 plug. No problems, and no worries. Just be sure to give it a good shove, so it is connected nice and tight. If it can be done in Chicago, California should be a piece of cake," writes a forum user named GoTeslaChicago.
What has been your experience of charging your EV in the rain?