silver storm vs violent storm

silver storm and violent storm both are nouns.

Word	Noun	Adjective	Verb	Adverb
silver storm	Yes	No	No	No
violent storm	Yes	No	No	No

As nouns, violent storm is a hypernym of silver storm; that is, violent storm is a word with a broader meaning than silver storm:

silver storm: a storm with freezing rain that leaves everything glazed with ice
violent storm: a violent weather condition with winds 64-72 knots (11 on the Beaufort scale) and precipitation and thunder and lightning

Other hypernyms of silver storm include storm.

silver storm (noun)	violent storm (noun)
a storm with freezing rain that leaves everything glazed with ice	a violent weather condition with winds 64-72 knots (11 on the Beaufort scale) and precipitation and thunder and lightning