It’s December tomorrow. Please remember to take appropriate front and rear lights on all rides until the spring (except possibly morning training rides, depending on the forecast).
It might be sunny when you leave but the weather can change very quickly at this time of year, particularly in the hills. And you may be delayed if you or another member of your group has an accident or a mechanical.
If you’re not sure which lights will suit you best, please just ask another Wheeler. Between the 270 of us, there’s a few thousand years of experience in riding in low light and at night.