25 across
Road
not
negotiable
in
this
(7)
Road not negotiable in this (7)
hints
0
checks
0
hints
The whole clue is the definition (& lit or double definition).
How the clue works
The whole clue works as an &lit — the surface reading is literally true, since a road would indeed not be negotiable in a tornado. The wordplay has "negotiable" doing double duty as the anagram indicator, and scrambling ROAD NOT gives you your answer.