Cryptic crossword No 3,569

Across

1. Obfuscated coteries known only to few (8)
2. A cluster of notes heard in harmony (6)
3. Grounds for studying group discussion centrally (6)
4. Set out, or be my baby, soon? (6)
5. Getting prepared, core of team boards airliner, finally about to depart (8)
6. Endlessly starry-eyed, newly embracing closure of one's days gone by (10)
7. Dessert with dash of flour, two eggs and head of lettuce (4)
8. After cutting back, stress about a wild plant (6)
9. Whirlwind threat is one that could produce Sou'wester, perhaps? (6)
10. Acidity level of 100, yet to lose heart in case of Lyme's disease killers? (11)
11. Outside view of bronze body (5,5)
12. Scottish lake within castle's walls provides cover to fish, perhaps? (6)
13. Once, you and I put up Tenzing, foremost Himalayan snowman (4)

Down

1. News caster? (8)
2. Artful cushions portray, soullessly but with right impression, how an acrobat moves, perhaps? (6)
3. On an annual cadence, nobility stands in when yeomanry gets gutted (6)
4. Our star handyman, seen halfway through taking a period of rest at the end of the week (6)
5. Turning on an axis, or turning on a vacant runway, taking time (6)
6. Smoking pipe is my niche when troubled (7)
7. Forever rent 12 asunder (8)
8. Travel from outskirts of Nice, after day in French city's ending (7)
9. Bellyaches, typically when x-rayed for type of cough (6)
10. Refrain from returning government benefits, with my coverage (6)
11. Hoard containing silver and rarely excavated deeds of barbarians, perhaps? (8)
12. High society is to fracture, ending early in a first in recent history, at last (11)
13. Ability to produce unoccupied, empty housing starts to fall for illegal construction agencies, countrywide (8)