( ( The ( National ( Weather Service ) ) ) ( ( said ( ( wintry precipitation ) ( will ( ( ( move ( behind ( ( the front ) ( on Tuesday ) ) ) ) , ) ( when ( ( ( Pacific ( moisture streaming ) ) ( from ( Mexico ( and ( New Mexico ) ) ) ) ) ( ( ( collides ( with ( the ( cold front ) ) ) ) and ) ( triggers ( ( a band ) ( of ( snow ( and ( freezing rain ) ) ) ) ) ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT The) (NNP National) (NNP Weather) (NNP Service)) (VP (VBD said) (SBAR (S (NP (JJ wintry) (NN precipitation)) (VP (MD will) (VP (VB move) (PP (IN behind) (NP (NP (DT the) (NN front)) (PP (IN on) (NP (NNP Tuesday))))) (, ,) (SBAR (WHADVP (WRB when)) (S (NP (NP (NNP Pacific) (NN moisture) (NN streaming)) (PP (IN from) (NP (NNP Mexico) (CC and) (NNP New) (NNP Mexico)))) (VP (VP (VBZ collides) (PP (IN with) (NP (DT the) (JJ cold) (NN front)))) (CC and) (VP (VBZ triggers) (NP (NP (DT a) (NN band)) (PP (IN of) (NP (NN snow) (CC and) (NN freezing) (NN rain))))))))))))) (. .)))
The National Weather Service said wintry precipitation will move behind the front on Tuesday, when Pacific moisture streaming from Mexico and New Mexico collides with the cold front and triggers a band of snow and freezing rain.
(ROOT (NP (NP (NP (NNP Precipitation)) (ADJP (RB commonly) (JJ occur))) (PRN (-LRB- -LRB-) (PRP s) (-RRB- -RRB-)) (PP (IN along) (NP (DT a) (JJ cold) (NN front))) (. .)))
Precipitation commonly occur(s) along a cold front.