High altitude wind from Blackburn? (3,6)
I believe the answer is:
jet stream
'high altitude wind' is the definition.
'jet stream' can be an answer for 'wind' (jet stream is a kind of wind). I am not certain of the 'high altitude' bit.
I don't understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for jet stream that I've seen before include "High-altitude, high-speed wind" , "High atmospheric westerly current" , "flow behind aircraft" , "Strong westerlies" , "Upper atmosphere current" .)