THE heavens well and truly came down for the opening day of the Killarney Show today but it won't dampen spirits for the rest of the weekend.

Killarney Show Society president Jan Hamilton said facilities at the Killarney showground were up to the challenge of the testing weather.

"We can handle 80mm of rain and be perfect for Saturday because of how dry it has been,” Mrs Hamilton said. "We're optimistic for Saturday because the grounds can handle the water.”

Despite gloomy skies and constant rain during the early part of the first day, events have gone ahead as planned, with Mrs Hamilton urging people to get behind the show over the weekend.

"The prime cattle went off without a hitch and the dog trials have been going well also,” she said.

The Killarney Show hasn't had the best of luck in recent times, with two shows in the space of three years being cancelled due to wet weather, but Mrs Hamilton didn't expect that to be the case in 2018.

"We're hoping people come down. We encourage people to wear appropriate footwear and check the weather forecast,” she said.

"The veranda area of the pavilion is 38 metres long and six metres deep and has a good view of the grounds.”

Tomorrow's forecast for Killarney is brighter than today's, with a top of 29 degrees predicted and just 5-10mm of rain expected.

Sunday will have a top of 30 degrees, with 10-20mm of rain has been forecast.

Check updates on the Killarney Show Facebook page for tonight's rodeo.