ACROSS

After rains, ark rested atop this initially (6)
Apparently everything revolves around this celebrity from Warsaw? (4,4)
Be indecisive about aid agency, for example, as a result of too much wine? (8)
Considered carefully how wine may be served at Christmas (6)
Engine part damaged in post (6)
Gradually gather ship's company, it's said (6)
Maybe sling or prepare to fire one who follows (8)
Resoundingly moving performance (3, 5)
Save for later, when sailor's at sea (4,4)
Scottish football team's last defender makes cross (7)
Second in the series about one who will be queen? (7)
Society in Arab state - people who'll always agree with those in power (3-3)
Well-dressed Christmas tree (6)
Went over again alternately in their vast herds(8)

DOWN

1. First report into state of the sea (6)
2. One with an hourglass figure, and handy in the kitchen (3-5)
3. What one achieves with iron at the end of one's days (8)
4. Equatorial region's king surrounded by subjects (7)
5. Count repellant bulbs? (6)
6. Hound is a second-rate thing of value (6)
7. Horseman wrecked a vile car(8)
15. Charm one's way in (8)
17. Collect donkey symbols, mostly (8)
18. Girl also assaulted primates (8)
19. Commercial part of song is not favourable (7)
21. Jockeys' contract extensions (6)
22. Silent shimmering Christmas decoration (6)
24. Roman leader's reported order that woman be arrested (6)