Usage patterns
降りが強くなるthe rain/snow gets heavier
The rain has been getting heavier since evening.
〈乗り物〉の乗り降りgetting on and off a vehicle
Please be careful when getting on and off the bus.
降りが弱まるthe rain/snow lets up
The rain should let up after midday.
Expressions
降りみ降らずみraining on and off; intermittent rain