In like a lion, out like a lamb

News about the pandemic seemed to push aside the usual stories on the news about the weather. “In like a lion, out like a lamb” has always seemed a straightforward enough proverb about the weather in March. March begins in winter, and by the end of the month, spring has begun, so it is often a mean lion at the start and a gentle lamb at the end. 

Some websites call the phrase an 18th-century expression. A 1732 citation lists it as “Comes in like a Lion, goes out like a Lamb.” Wikipedia says it originated in Pennsylvania. 

There is even a celestial explanation. In March, Leo is the rising sign but by April Aries is rising. (Ram, kid, lamb?) 

It is less frequently applied to situations where someone starts strongly and ends weakly, as in " The President came in like a lion but went out like a lamb."