How to say "on Fridays" vs "this Friday"

きんようびのよるはともだちとでかけます

From what I can tell, this could either mean:

"I go out with my friends on Friday nights." OR

"I will go out with my friends on Friday night." (implying this Friday)

When someone uses this kind of grammar, is context the only way to tell what they mean? If I used the "ni" particle instead of "wa", would that mean "this Friday"? As in:

kinyoubi no yoru NI tomodachi to dekakemasu