You would hope a large well-established car company performs due diligence in testing charging in all weather conditions. Rest assured no high voltage is present until the EV performs continuity checks upon plug-in, especially with DCFC.
If there is a problem with water retention and subsequent corrosion, no one's posted about it yet. There have been posts about dirt and contamination affecting the charging ports, but I think it was actually due to a poor latch switch.