Is it probable for an I.P. address to show one city...?

...while the person who uses that computer is actually in another, 500 miles away? I've been casually emailing with an ex's ex (not quite the norm, believe me-- I know) for the past 3 months or so. She states she now resides in San Francisco (a former San Diego transplant), yet when I used several I.P. look-up sites to investigate her I.P. address, the city always comes back as San Diego. If she bought her computer in San Diego, would the I.P. travel and reflect as San Diego (admitted computer novice here)...or is this person actually nowhere physically near San Fran? Any advice or input on I.P. addresses relating to their users' general physical location would be appreciated. Thanks much.