5 are highly correlated during summer months in some areas.
( 5 ( ( are ( highly ( correlated ( during ( ( summer months ) ( in ( some areas ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (CD 5)) (VP (VBP are) (ADJP (RB highly) (JJ correlated) (PP (IN during) (NP (NP (NN summer) (NNS months)) (PP (IN in) (NP (DT some) (NNS areas))))))) (. .)))
Six are correlated to winter in certain areas.  
( Six ( ( are ( correlated ( to ( winter ( in ( certain areas ) ) ) ) ) ) . ) )
(ROOT (S (NP (CD Six)) (VP (VBP are) (VP (VBN correlated) (PP (TO to) (NP (NP (NN winter)) (PP (IN in) (NP (JJ certain) (NNS areas))))))) (. .)))