The blaze on Bridge Road, Southall, has been declared as a major incident after it was first reported at 8.55am.
Roughly 150 firefighters have been dispatched to the scene to tackle the fire, but have been forced to withdraw to a safe distance after explosions have been heard coming from the commercial building.
It is understood that the warehouse is housing suspected fireworks and cylinders.
A huge plume of thick, dark smoke has been pictured rising from Bridge Road, which has seen around 60 calls made to the Fire Brigade control room.
Residents in the local area have been advised to keep doors and windows closed due to the large amount of smoke being produced by the incident.
The pictures have also captured flames tearing through the roof of the warehouse.
Around three-quarters of the structure is currently alight.
Three turntable ladders have been deployed to scene, allowing crews to fight the fire from height.
Ast Com Pat Goulbourne, the Brigade’s Incident Commander, said: “Firefighters are working hard to bring this fire safely under control.
RELATED: Shocking video shows explosions as HUGE fire burns in London ‘fireworks warehouse’
“The incident involves a mixed retail and warehouse space, with a significant part of the structure currently alight.
“Due to the complex nature of the site, and the size of the fire, this will be a protracted incident with crews continuing out firefighting operations through the day.”
The cause of the fire is not yet known.
