IT IS getting so hot in outback Queensland that roads are melting and some rail services are being halted.

The Bureau of Meteorology says heatwave conditions are continuing over much of the western half of the state.

A severe to extreme fire danger warning is in force for the Channel Country and parts of the Maranoa and Warrego district.

The weather bureau warns those areas face temperatures above 45C.

Train services in central Queensland are being slowed down, with some grinding to a complete halt.

Queensland Rail confirms that the Spirit of the Outback service was terminated at Emerald yesterday and passengers are being taken by bus to Mount Isa.