Heavy rainfall caused significant flooding in the Main Street and Castlecat Road areas of Bushmills in Co Antrim on Thursday.
One UTV viewer, Paul McArthur, submitted footage of a bus trying to make its way through flood waters in the village.
A yellow warning for rain has been issued by the Met Office with the possibility of between 20 and 40mm falling in a short space of time.
It remains in place for Friday, as heavy showers are expected, particularly across southern areas, overnight and during the early hours.
"The public should be aware of the risk of localised disruption to travel due to surface water flooding," forecasters explained.
"The start time of this warning has been brought forward to cater for the risk of localised disruption associated with the heavy overnight rain moving north across parts of Northern Ireland, northwest England and southwest Scotland."
Heavy rain caused reduced visivbility on the M1 motorway earlier between junctions 10 and 13, and in Antrim there were also reports of localised flooding on the roads.
Police also advised to avoid the Main Street and the Garvagh Road areas in Dungiven, Co Londonderry.
Sandbags were handed out in parts of Belfast in anticipation of further flooding on Thursday night.
Heavy rain caused flooding overnight in parts of Dublin, where the city's fire brigade were operating as many as 20 engines at one stage.
A portion of the roof in the Mater Hospital and in Clery's Department Store fell in.
Several homes were affected by floodwater and some DART rail services have been suspended due to lightning damage to overhead lines.
The warning comes after nearly three weeks of summery weather in NI.
Thursday's top temperature is 22C.
"There will be a cloudy start with heavy thundery showers, still with some local torrential downpours, soon clearing north," the Met Office added.
"Then brightening with some sunshine though further thundery and torrential showers developing, and maintaining the risk of flooding especially in central and western areas."
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