It came as around 70 firefighters were battling a bushfire on Sunday night that swept across grassland and burned residents’ terraces in west London.
Smoke was visible to passengers landing at Heathrow Airport after the fire broke out in Feltham around 4.30pm on Sunday.
The Metropolitan Police told people to stay away from Hereford Road.
Several weeks of dry weather in the south and east, and a forecast for more hot conditions and no rain next week have raised concerns that more wildfires could start and spread, threatening lives and homes.
Neil Fenwick, Essex County Fire and Rescue Service Area Manager, said: “While summer weather is usually the perfect opportunity to have an evening barbecue or gather around a chimney, we strongly discourage people from having any kind of fire at the moment.
“The ground across Essex is extremely dry, allowing fires to spread easily and quickly. This applies to gardens as well as fields and heathland.
“Please don’t have barbecues or bonfires. Please don’t use fireworks or light sky lanterns. This could start a large-scale fire like we saw tonight.”