Gympie has a humid subtropical climate. Summers (December–February) are hot, humid, and prone to heavy thunderstorms; daytime temperatures sit around 30°C and can be uncomfortable. Winters (June–August) are dry and pleasant, with daytime temperatures around 21°C and cool nights.
The signature local event is the Gympie Muster, held over four days in late August at Amamoor Creek State Forest about 30 km south of town. It's one of Australia's biggest country music festivals — over 100 acts, tens of thousands of attendees, and a strong bush-camping atmosphere. Book accommodation and tickets well in advance.
The other date worth knowing is the annual Gold Rush Festival in October, which celebrates the town's mining heritage with parades, a re-enactment camp, and street stalls along Mary Street.