The advisory, released this week, cautions World Cup tourists about what the groups describe as the risk of arrest, detention and deportation, invasive social media screening, the risk of cruel treatment or death in an immigration facility, and suppression of speech.
The World Cup kicks off in mid-June, with matches scheduled across North America, including in Santa Clara and 10 other U.S. cities.
"It's going to be happening in our backyard," said Mariana with the Santa Clara County Rapid Response Network, one of the groups supporting the advisory.
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Organizers say the advisory is not meant to deter fans from attending games, but rather to prepare them.
"We're not discouraging people from coming to Santa Clara. We're not discouraging people to travel to the US for the World Cup. We are just encouraging people to be aware of the risks and be aware of their rights," Mariana said.
Recommendations in the advisory include turning off facial recognition and fingerprint passwords on phones, alerting family and friends of travel dates and destinations, and consulting "know your rights" resources.
Santa Clara City Councilmember Karen Hardy said she does not want the advisory to become sensationalized.
"You're raising people's blood pressure with things that have happened in the past or elsewhere. This is California, this is Santa Clara County," Hardy said. She also said she would be surprised to see immigration enforcement activity at games. "They're trying to be quiet and they're trying to be stealth. And that would not be either one of those."
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The advisory's authors say they are simply trying to inform visitors.
"It's not fear mongering. It's just us being responsible and letting people know what's happening in this country," Mariana said.
Santa Clara's vice mayor said the city has hosted international events before and that the goal is for visitors to not only be safe, but to feel welcome.
The first World Cup game in Santa Clara is scheduled for June 13.