Big Narstie looked a little confused when he saw a map of the UK, and revealed gaps in his knowledge during a weather forecast.
The rapper gave an alternative to the Queen's speech on the morning programme before talking about his upcoming show, where he raps about Mel B and Pamela Anderson as they watch on awkwardly.
After this he wandered over to the weather as Alex Beresford was doing his weather forecast, and quickly the gaps in Big Narstie's geography knowledge were made clear.
Alex beckoned the rapper onto the show as he was clearly angling for a little bit more TV time, but quickly his efforts doing the weather were not great.
He pointed down at St Helier, saying: "St Helier, what is that?"
Alex told him it was the Channel Islands, and the rapper clearly had no concept of what that meant.
The weatherman continued, saying: "It's the Channel Islands, in the English Channel! But anyway we;ll talk abotu this after the show, metry christmas it's my life day!"
Then Big Narstie pointed at a town in Scotland, saying: "Oban? What's Oban?"
Alex giggled as he told him where the city was, but then Ben Shephard joined in, telling the group that Alex would give the rapper a geography lesson before the show finishes.
The GMB twitter pair showed off a clip of the show, saying: "That's one way to wrap up the weather... thanks @bignarstie. @ alexberesfordTV will be giving a quick geography lesson after the show"
Another viewer tweeted: "Clearly! basic geography isn't taught in schools anymore. Bloody hell"
Before that, the rapper shared how much he "respected" Charlotte Hawkins and Kate Garraway for putting on make-up "so early," after doing an important message for the nation.
In his message, he commanded viewers to: "Eat, laugh, drink, be merry. Narstie glue, Narstie cherry..."
Good Morning Britain airs weekdays at 6am on ITV.
