One of the factors we have to take into account was how likely it was that another mariner would have stumbled on the Americas in the late fifteenth or early sixteenth centuries.
By way of evidence, look at how the Portugese Pedro Álvares Cabral (this article) pretty much bumped into Brazil by accident.
Note the way in which it happened: “The fleet of thirteen ships left Lisbon on 9 March 1500, and following the course laid down, sought to avoid the calms off the coast of Gulf of Guinea. On leaving the Cape Verde Islands, … they sailed in a decidedly southwesterly direction. On 22 April a mountain was visible, to which the name of Monte Pascoal was given; on the 23 April Cabral landed on the coast of Brazil, and on the 25 April the entire fleet sailed into the harbor called Porto Seguro.” (emphasis added)
Now, it may seem odd to believe that someone would “stumble” across the Atlantic, but consider the relative positions of Portugal, Africa (around which the Portugese were sailing regularly) and the easternmost part of South America.
So why was Cabral going so far west if he was trying to get around Africa? Because if you look at the way the trade winds blow, you will see that between Portugal and the Equator, they blow south-west: that is, directly towrds the new world! Then there is an area of calm around the Gulf of Guineau, but the winds south of the equator tend to blow northwest.
Mariners in the age of Cabral had gotten the hang of going further west to get a better break with the winds when going around Africa.
Also, in the age of sail, you did not always choose your route exactly. Strong winds often chose for you. Cabral probably noted that he was swinging a little further west, but probably did not mind as long as he was heading south as well.
You will note that Cabral and his 13 ships (much more than Columbus) were NOT blown off course by a hurricane. Indeed, the article says the “entire fleet” sailed to Brazil once they spotted it.
Now, consider this article about the trade winds and currents here Consider especially the last two paragraphs:
"For eighteenth century navigators, the Atlantic trades winds, and the currents they generated, provided a reliable means of crossing from the Canary Archipelago and then heading north with the equatorial current through the islands of the Lesser Antilles into the Caribbean.
It also gave voyagers a way of reaching the Cape of Good Hope without having to sail against the northerly South African Current. They could cross the Atlantic, head southwards of Cabo São Roque with the Brazil Current and then sail back across the Atlantic to the Cape of Good Hope with the Southern Connecting Current. "
**Conclusion: The Atlantic winds, the currents, the lay of the land. . . . . everything made it more of less inevitable that Europeans of the fifteenth century with their improved navigation and sailing techniques would happen onto the Americas.
And that is exactly what happened a mere 8 years after Columbus’ voyage.**