Effect of cold and wind at the moment stopping first date working out (9)
I believe the answer is:
snowdrift
'effect of cold and wind' is the definition.
'at the moment stopping first date working out' is the wordplay.
'at the moment' becomes 'now' (I've seen this before).
'stopping' means one lot of letters goes inside another (stopping can mean blocking a gap).
'date' becomes 'd' (common abbreviation eg in DOB, date of birth).
'working out' is an anagram indicator (an anagram must be worked out from the letters).
'first'+'d'='firstd'
'firstd' with letters rearranged gives 'sdrift'.
'now' inserted within 'sdrift' is 'SNOWDRIFT'.
(Other definitions for snowdrift that I've seen before include "Wintry feature" , "evidence of wintry weather" , "Winter problem" , "Midwinter may show one" , "Feature of winter weather" .)