inclement
Harsh, unpleasant weather that makes being outside difficult or unsafe.
Inclement describes harsh, severe weather that makes being outside unpleasant or even dangerous. When weather forecasters warn about inclement conditions, they mean storms, heavy rain, ice, snow, or bitter cold that could make travel risky or force schools to close.
A sunny spring day is pleasant; a winter blizzard with howling winds and icy roads is inclement.
Schools might cancel outdoor recess due to inclement weather, or a camping trip might get postponed when forecasters predict inclement conditions. Sports teams sometimes have to move games indoors or reschedule them entirely when the weather turns inclement.
While inclement almost always describes weather, you might occasionally hear someone use it more broadly to mean harsh or unmerciful, like an inclement judge who shows no leniency. But in everyday conversation, when you hear inclement, think of weather nasty enough to make you grateful for a warm house and a roof over your head.