Season and Weather
Pern has 13 months of 28 days each, with two leftover days at the end given over to Turnover.

Season: Summer, Month 10-13, Turn 24 AM
Weather: A stormy, humid summer, the plants are all growing well. Even when it's not hot it seems unbearable because of the humidity - until a storm breaks, then a day or two after there will be hot but not unpleasant weather. There is usually at least one storm a sevenday.

Turn 11 AM: Ierne-M'genathril Weyr is founded.

Turn 20 AM
Month 5, Day 26: H'ilo and bronze Politeth go missing during a routine fishing trip.
Month 6, Day 3: Goldrider Bortinya is diagnosed with a non-lethal strain of the plague and is quarantined so as not to spread it through the rest of the weyr.
Month 8, Day 5: Gold Kiyemith Flies and is caught by Brown Mistryth.
Month 10, Day 22: Gold Kiyemith lays a clutch of 19 eggs on the Hatching Grounds, including two large eggs and one egg everyone assumes holds a queen.
Month 10, Day 26: Goldrider Bortinya goes into labor and dies. Her daughter, Ilonya, is sent to live in Ierne Hold.
Month 12, Day 12: Gold Kiyemith's clutch hatching is met with a mixture of joy and grief--joy because the weyr has grown and grief because they have lost their queen.

Turn 21 AM
Month 5: Kittenflies were discovered.

Turn 22 AM
Month 6, Day 2: Kiyemith's last clutch graduates from weyrling training.
Month 6, Day 19: A sea monster attacks a ship and kills a green. While battling the monster, riders experience various effects and become aware of new creatures in the water, the most prominent underwater creatures whose upper half resembles a runnerbeast's.
Month 8, Day 26: Tavarith Flies and is caught by V'anric's brown Ronilerth.
Month 13, Day 3: Tavrith's first clutch of a mere seventeen hatches.

Turnover: The Lycoris reveal themselves.

Turn 23 AM:
Month 2, Day 4: The Holdless attack on a small hold gains the wher a clutch of strange wher eggs.
Month 2, Day 24: After the Weyrleader decides there is potential in having whers around the wher, the eggs are allowed to hatch at the Hatching sand, spilling out new colors and mutations into the world.
Month 10: A book is published that discusses a new opinion - one that says that the Meteor is a wonderful thing to happen to Pern. It is initially dismissed.

Turn 24 AM:
Month 1, Day 18: Tavarith Flies - and once again changes the leadership as she is caught by Satyrith, the only adult Bronze.
Month 2: Sales of the Book of the Meteor as it has been termed, begin to pick up.
Month 4, Day 5: A clutch of 23 eggs is laid.
Month 5, Day 23: Tavarith's clutch of 23 eggs hatches and Rowyn Impresses the Quartz Emeraith, who will eventually prove to be a Queen.
Month 6, Day 10: Green Zith's clutch of 2 eggs hatches the first Pearls to be seen on Pern and Sa'nor and E'zekial become the Weyr's first Pearlriders.