U.S. police say they arrested him after the weapons were discovered at the Hyatt Regency in downton Houston in the early hours of Sunday morning.
A hotel spokesperson told the website the party will go ahead as planned but with extra security. They also found other weapons in his pickup truck.
He called for back up, and when officers arrived, they searched the suspect's room, on the top floor of the hotel, and found a rifle, shotgun and handgun in his room, plus ammunition.
The man is now in police custody, facing charges of trespassing and unlawful carry, and as of mid-morning Sunday, reportedly waiting to sober up before investigators can continue with their questioning.
The officer called for an urgent backup around 1:30 a.m. after he encountered the man, whom he described as erratically and belligerent, according to ABC Eyewitness News. They're going to check his vehicle to see if there's more weapons in it.
Despite the discovery, hotel officials said they are still hosting tonight's New Year's Eve celebration, which is reportedly set to host a massive 50,000 balloon drop at midnight.
Houston Police Chief Art Acevedo confirmed via Twitter on December 31 that the situation is contained and that there are "no specific threats" to Houston. Tom Netting, the managing director at the Hyatt Regency Houston issued the following statement in response to the arrest: The safety and security of our guests and colleagues is our top priority, and we are fully cooperating with authorities on an ongoing investigation after an individual was taken into their custody this morning.