Basejumper.com

If it's an ordinance by the city, then it shouldn't be a jailable offense, just a fineable offense. The state, however, can pass laws that are jailable.

"Wind patterns are unpredictable and easily could push a glider into another structure. There's the chance the parachute could become tangled in wires or could malfunction, leaving the jumper to fall hundreds of feet to the pavement, he said."

That's probably not the case. Depending on the class of the city, in most states, city ordinances can be violations or misdemeanors. In both cases the peace officer has the power to ensure that the offender appear before the court by detaining him.

In the case of a violation it is usually preferred that the violator be cited and allowed to present himself to the court at a future date. If the violator indicates his unwillingness to do so (like wadding the citation up and throwing it away), the peace office will generally compel the violators presence by arrest.

By the same token, though it is generally preferred that offenders (those committing criminal offenses) be arrested, on a misdemeanor charge, if the peace officer believes the offender WILL present himself before the court, he MAY cite the offender to court rather than arrest him.

The two points being that cities generally do have the power to create criminal law, and that those enforcing laws have some discretion in whether to cite or arrest. If you are reasonable, local, sober, and ask nicely, you may be able to talk yourself into a citation rather than a trip to jail. And if you are the opposite, you can certainly talk yourself into jail.