Tempest is a large set with 110 commons, 110 uncommons, 110 rares, and four variations of each standard basic land. This is smaller than previous large sets (due to a change of the print sheet size), but this size goes on to be normal for a large set. The set was printed in the USA and Belgium.

Tempest was sold in 15 card booster packs. Booster boxes have 36 packs.

The US printing uses sequential collation with 10 × 11 sheets. Packs are back-facing and contain 11 commons, 3 uncommons, and 1 rare. There are two different possible orderings. Commons are always first, followed by two uncommons. Then, some packs have the rare before the last uncommon, and other packs have the rare last. Basic lands do not appear in booster packs.

11 Commons | 2 Uncommons | 1 Rare | 1 Uncommon |

11 Commons | 3 Uncommons | 1 Rare |

Starter decks have 3 rares, 9 uncommons, 26 commons, and 22 basic lands in addition to a rulebook. Observed decks are front-facing. The rulebook is first, then commons, uncommons, rares, and land. Decks have an outer seal, but no inner seal.

Rulebook | 26 Commons | 9 Uncommons | 3 Rares | 22 Lands |

Commons have the same basic structure as Mirage. There are four common runs. Two, A and B, have 30 cards (each twice) and two, C and D, have 25 cards (again, each twice). Each pack contains 6 commons from A and B followed by 5 from B and C. The A and B commons can be in A-B order or B-A order. Either way, the split will be either 3-3 or 4-2. The C and D commons can also be in either order independently of the ordering of A and B. (It is possible that these ordering are correlated in the same box, but I haven't seen a booster box opening.) Their split will be 3-2 or 2-3.

Starter decks are a bit messier. They can be split either 15 from A and B and 11 from C and D, or 13 and 13. Mathematically, the 15-11 split should happen 13/22 of the time. If there are 15 A and B, they will be split 7-8 or 8-7. If there are 13 A and B cards, the split will be 6-7 or 7-6. Likewise, 11 C and D will be split 5-6 or 6-5 and 13 C and D will be split 6-7 or 7-6. Like booster packs, A and B can appear in either order, and so can C and D. In the cases I've observed these orders are correlated (always A and D first or B and C first), but it's possible this is just due to small sample size. (Within the same box, at least, they are probably correlated.) Like boosters packs, A and B come before C and D.

Note that there is apparent symmetry between A and B and between C and D, so the labels here are arbitrary.

There is a picture of one of the common sheets (containing B and D). [1]

Run A contains 30 cards each twice. Cards are in a repeating color pattern of white, black, green, red, blue. By the process of elimation, we can except it is printed on the top half of the same sheet as C. The choice of first card is mostly arbitrary.

Run B also contains 30 cards each twice. Cards are in a repeating color pattern of white, blue, black, green, red. The common artifacts are also in this run, replacing cards of each color. It is printed on the top half of the same sheet as D.

Run C contains 25 cards each twice. Cards are in a repeating color pattern of white, black, green, red, blue. By the process of elimation, we can except it is printed on the bottom half of the same sheet as A. The choice of first card is mostly arbitrary.

Run D contains 25 cards each twice. Cards are in a repeating color pattern of white, black, green, red, blue. It is printed on the bottom half of the same sheet as B.

The Belgian printing uses striped collation with 10 × 11 sheets. Packs are back-facing and contain 3 uncommons, 1 rare, and 11 commons (in that order). Basic lands do not appear in booster packs.

3 Uncommons | 1 Rare | 11 Commons |

Starter decks have 3 rares, 9 uncommons, 26 commons, and 22 basic lands in addition to a rulebook. Observed decks are front-facing with lands followed by rares, uncommons, and commons. The rulebook is between the rares and uncommons. Decks have both an inner and outer seal.

22 Lands | 3 Rares | Rulebook | 9 Uncommons | 26 Commons |

There is a single sheet that prints each common once. Note that Sea Monster was not observed in any pack openings, so its placement is only by process of elimination. The top row is chosen to avoid red and green cards from appearing next to each other on the sheet.

[1] The "Compilation of Uncut Sheets" thread on the Magic Librarities Forum has a picture of one of the US common sheet (with runs B and D).