The storm lasted for about half an hour, starting at about 6pm and finishing about 6.30pm.
Omakau resident Vicky Orbell said the storm was "horrendous."
"The hail was so loud I couldn’t hear the thunder," she said.
Ms Orbell said Omakau had 25ml of rain in 25 minutes and Ophir 45ml of rain.
She thought the storm was very localised.
"5km [north] up on Racecourse Rd there was only a bit of rain," she said.
Fire and Emergency New Zealand Southern Communications Centre shift manager Andrew Norris said one fire truck and one medical unit truck from Omakau were called to Ophir at 6.50pm last night.
Mr Norris said there was reports of flooding, particularly in Swindon St in Ophir.
"It was basically a deluge that overwhelmed their drainage system."
Mr Norris said the fire service used a portable pump to divert the drain water away.
The fire service stayed in Ophir for about an hour and no people were hurt or homes evacuated, he said.
