The Department of Environment, Food and Agriculture has described the risk of wildfires during TT as "very high".
It says upland and lowland habitats are tinder dry, and winds are creating a very high risk.
In those conditions, the department says one spark could set off a blaze threatening wildlife, livestock, public safety and even TT racing.
It's urging people to take extra care in the countryside, adding rain is forecast in a few days' time.
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