I hope some of the comments are jokes
Rain (precipitation) affects us physically and psychologically; and no one in their right mind would deny the significant change in physics involved while riding a bike (or any mechanical device) during a rainstorm or wet conditions.
Its also
#1 when it comes to corrosion and significant damage to ALL materials -- metals, and composites. There's so much information to the contrary of positive, that it could fill a database. Basically, the opposite of some "good for you" statements.
"
Of those deaths and injuries related to weather, 46% occurred during rainfall, and fully 73% occurred on wet roads. When you contrast those statistics with the 27% of accidents that occurred during snowy and icy road conditions, it is even clearer that wet road conditions are perhaps the single greatest weather-related accident risk factor today’s drivers face."