A cycling expert's forecast (5)

I believe the answer is:

augur

'forecast' is the definition.
('augur' can be a synonym of 'forecast')

I don't understand the remainder of the clue.

(Other definitions for augur that I've seen before include "Portend, herald" , "Signal" , "Promise" , "Presage, foretell" , "Bode, foretell" .)

I've seen this clue in The Guardian.

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