I found this blog post a guy made on manipulating WiFi from command line. It's self-explanatory, so I'll copy-paste it and link to it. Many thanks, Matt Crampton!!
ORIGINAL LINK
ORIGINAL LINK
Turn off wifi on your macbook from the Mac OSX terminal command line:
networksetup -setairportpower en0 off
Turn on wifi on your macbook from the Mac OSX terminal command line:
networksetup -setairportpower en0 on
List available wifi networks from the Mac OSX terminal command line:
/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airport scan
Join a wifi network from the Mac OSX terminal command line:
networksetup -setairportnetwork en0 WIFI_SSID_I_WANT_TO_JOIN WIFI_PASSWORD
Find your network interface name
networksetup -listallhardwareports
