Cryptic crossword No 3,667

Across

1. Encounters early signs of cold front during races (14)
2. Samurai art shows man’s drip after operation (13)
3. Film producer arrived with big guns (6)
4. First person adopted by matriarchs displays confusion (8)
5. Mum has moments setting tables (8)
6. Rarest sheep carried by foot (6)
7. When Christmas comes is one’s head shilly-shallying? (14)
8. A policeman arrests doctor after papers possibly swallowed by child (4,4)
9. Scented acer cultivated with new name: Supremacy (13)
10. Without punctuation ‘e might… (6)
11. Drink Edward put down (8)
12. Good thing whistle-blower conceals deception (6)

Down

1. Wonky corner peg in field of clover getting dug in? (5,4)
2. … pardon Hugh appearing without George initially (3)
3. Smallest expression of hesitation after note sent back unaltered (7)
4. Rank taste (5)
5. Essentially Gregory and I… (3)
6. … with twisted double helix (3)
7. Quiet niche I abandoned catastrophically for procedure… (9)
8. Exhausted politician held by stranger with terrorist weapon (7)
9. On the level plain (15)
10. Virginia constrained by recurrent noise avoidance (7)
11. Facilitates cutting top off ribs (5)
12. Distinction provided by retiring judge, unusually patient though powerless, in Dublin famously (15)
13. Heart of Genet’s novel (3)
14. Returning from MIT I remember its honoured retirees? (7)