Too many variables to say.
I've frozen my arse off in May and been somewhat comfortable depending on bivvy location, time, what shelter was available, whether I was using a sleeping pad, clothing choice, fatigue.
I'll send a polite email to the organiser ;)
If there's sleeping available I'd use it. Lightweight bivvying sucks, particularly in the UK when it's getting down towards or below 0degC at night.
@MicroDosed™ started
London Fixed Gear and Single-Speed is a community of predominantly fixed gear and single-speed cyclists in and around London, UK.
This site is supported almost exclusively by donations. Please consider donating a small amount regularly.
Too many variables to say.
I've frozen my arse off in May and been somewhat comfortable depending on bivvy location, time, what shelter was available, whether I was using a sleeping pad, clothing choice, fatigue.