From shakespeare's the tragedy of romeo and juliet

note: juliet's father angrily speaks to his crying daughter.

"thou counterfeit'st a bark, a sea, a wind;
for still thy eyes, which i may call the sea,
do ebb and flow with tears; the bark thy body is,
sailing in this salt flood; the winds, thy sighs;
who, raging with thy tears, and they with them,
without a sudden calm, will overset
thy tempest-tossed body."

what is the extended metaphor in these poetic lines?