( Blizzards ( ( are ( ( severe ( winter storms ) ) ( that ( ( ( pack ( ( a combination ) ( of ( blowing snow ) ) ) ) and ) ( wind ( resulting ( in ( ( very low ) visibilities ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Blizzards)) (VP (VBP are) (NP (NP (JJ severe) (NN winter) (NNS storms)) (SBAR (WHNP (WDT that)) (S (VP (VP (VB pack) (NP (NP (DT a) (NN combination)) (PP (IN of) (S (VP (VBG blowing) (NP (NN snow))))))) (CC and) (VP (VB wind) (S (VP (VBG resulting) (PP (IN in) (NP (ADJP (RB very) (JJ low)) (NNS visibilities))))))))))) (. .)))
Blizzards are severe winter storms that pack a combination of blowing snow and wind resulting in very low visibilities.
(ROOT (S (NP (DT A) (NN winter) (NN storm)) (VP (VBZ is) (VP (VBN called) (NP (DT a) (NN blizzard)))) (. .)))