"Omar's coming!"
In general people in the UK can understand most Americans. People in the US are fucking baffled when they hear someone from the UK say "herb" or "water".
To give a non-"street" example, one character makes a comment about working a "ro-ro" which I happen to know is a "Roll-on, Roll-off car ferry". But I guess the average viewer isn't supposed to know that, just to absorb the authenticity as a background texture.