In Book IX of Homer's, The Odyssey, who sends the storm, and why is it not Poseidon?
'Thence we sailed onward stricken at heart, yet glad as men saved from death, albeit we had lost our dear companions. Nor did my curved ships move onward ere we had called thrice on each of those our hapless fellows, who died at the hands of the Cicones on the plain. Now Zeus, gatherer of the clouds, aroused the North Wind against our ships with a terrible tempest, and covered land and sea alike with clouds, and down sped night from heaven. Thus the ships were driven headlong, and their sails were torn to shreds by the might of the wind. So we lowered the sails into the hold, in fear of death, but rowed the ships landward apace. There for two nights and two days we lay continually, consuming our hearts with weariness and sorrow. But when the fair-tressed Dawn had at last brought the full light of the third day, we set up the masts and hoisted the white sails and sat us down, while the wind and the helmsman guided the ships. And now I should have come to mine own country all unhurt, but the wave and the stream of the sea and the North Wind swept me from my course as I was doubling Malea, and drave me wandering past Cythera.
In Book Nine Odysseus and his men do eventually come across Poseidon; after "escaping" from the Lotus Eaters, they find themselves on the island of the Cyclopes, a godless group of creature who have no fear of, or respect for Zeus.
It is here that Odysseus and some of his men go ashore to see who inhabits this land. There they find a cave and enjoy its hospitality: food shelter. Soon, Polyphemus enters and defies the common laws of hospitality that Zeus demands for travelers and strangers: Polyphemus imprisons Odysseus and his men, and even eats some of the crew members.
The next morning, Polyphemus leaves, imprisoning Odysseus and his men for his return. Odysseus and his crew fashion a long pole into a large pointed weapon and get the Cyclops drunk when he returns. When the moment is right, they blind the giant.
The following day, Polyphemus still has no intention to free his captives, so Odysseus and his men tie themselves and hide beneath the bellies of the giant's herd: sheep and goats. As each animal leaves the cave, Polyphemus can only feel their backs to make sure no men escape. When Odysseus and all his men are free, they quickly return to their ships.
It his here that Odysseus is punished for "behavior unbecoming a Greek hero:" he taunts the blinded Polyphemus, and reveals his true identity. Unknown to our hero, the giant is a son of Poseidon. Polyphemus asks for Poseidon's curse to keep Odysseus and his men from reaching home, or if they must, that many years pass.
It is in this way that Poseidon becomes involved in Odysseus' tale in Book Nine.