Hounslow Heath was left blackened and charred after another grass fire broke out there on Sunday evening (August 5).
Three hectares of shrubland were destroyed by flames which firefighters worked into the night to control.
The fire was the latest in a long string which have broken out across Hounslow during the weeks of hot weather.
A London Fire Brigade (LFB) spokesman said: "Seven fire engines and around 50 firefighters were called to a grass fire on Hounslow Heath at 6.04pm.
"Approximately three hectares of grass and shrubland were alight.
"The fire was under control at 9.32pm, but crews [remained] on scene overnight. Fire crews from Twickenham, New Malden, North Kensington, Norbury and surrounding fire stations attended the scene."
Photographs taken at Hounslow Heath the following day show huge stretches of grassland left blackened and destroyed by flames.
According to the brigade discarded cigarette butts or glass bottles often spark devastating blazes in dry and hot conditions.
An LFB spokesman said: "During the hot weather we are attending a large number of grass fires across London.
"We’re asking the public to take care not to drop cigarettes or matches on dry grass and to keep a very close eye on barbecues.
"Dropped glass can also start fires as [it] can magnify the sun’s rays.
"Grass fires can quickly spread and cause serious damage, so if you see grass smouldering, please call 999 immediately."
There were four west London grass fires over the weekend, two of which were in Hounslow.
Two hectares of grass caught light in Wembley on Friday night (August 3) with four fire engines and 25 firefighters called to deal with the fire.
Three hectares of grass caught alight in Whitton on Sunday evening with seven fire engines and 50 firefighters called to that fire.
And as well as the Hounslow Heath fire on Sunday two hectares of grass caught alight near Pevensey Road in Feltham with three fire engines and 15 firefighters called to deal with the blaze.
LFB is urging councils across the capital to ban barbecues in public spaces during the heatwave.
LFB has also released a set of guidelines on how to prevent grass fires.
LFB's top tips on preventing grass fires:
- Never leave camp fires or barbecues unattended and extinguish them properly after you have finished using them
- Clear away bottles, glasses and any broken glass to avoid them magnifying the sun and starting a fire
- Dispose of smoking materials such as cigarettes safely
- Explain to children the dangers of playing with and lighting fires