🇺🇸 Chicago, Illinois, USA
Is It Cold at Night at Lollapalooza Chicago?
Overnight lows average 20°C across the main days, based on roughly 15 years of records at the site.
The short answer
Not really — Lollapalooza nights stay mild, averaging 20°C, with the coolest festival night near 19°C (Fri 31 Jul). A light layer is usually enough after dark.
A 1-season bag or even a duvet-style liner is enough — most nights you'll sleep on top of it, not in it.
Night by night
| Night of | Low | High that day | Rain |
|---|---|---|---|
| Thu 30 Jul | 19°C | 25°C | 1.1 mm |
| Fri 31 Jul | 19°C | 26°C | 1.7 mm |
| Sat 1 Aug | 20°C | 27°C | 1.5 mm |
| Sun 2 Aug | 20°C | 28°C | 3.8 mm |
Long-run averages, not a forecast. Individual years swing several degrees either side.
Sleeping warm in a tent
- Insulate underneath first. A cheap foam mat under an air mattress does more than a warmer bag.
- Dry clothes to sleep in. Damp festival clothes will keep you cold all night.
- A beanie and dedicated sleep socks — the cheapest comfort upgrade in the bag.
- Eat something before bed and don't go to sleep dehydrated; both make you feel the cold more.
Why nights matter to the weather score
Our festival weather score treats overnight lows separately from daytime highs, because a warm afternoon doesn't make up for a night you can't sleep through. Nights between roughly 10 and 24°C count as comfortable camping weather; below that the score starts to drop, and it drops sharply once lows fall under about 8°C.