Fire crews have rescued 93 people trapped by torrential flood waters, either from their cars or their houses.
The west has been worst hit, with nearly nine out of ten (87%) of rain-related call-outs happening there.
In all, the Northern Ireland Fire and Rescue Service (NIFRS) responded to 85 incidents on Tuesday night, at one point answering a call every 45 seconds.
Alan Walmsley, Assistant Chief Fire & Rescue Officer spoke of the difficulty for crews reaching people, with a number of roads left impassable by the rains.
“Firefighters worked in extremely challenging circumstances to reach people. A number of roads were impassable due to flooding and Crews had to take alternative routes to attend some incidents," he said.
The NIFRS worked alongside the Irish Coastguard, PSNI, Ambulance Service, Foyle Search and Rescue as well as local councils to respond to requests for help from the public.
In the event of serious flooding, there is a 24/7 service where staff can take your details and contact the appropriate agency on your behalf. You can call the NI Flooding Incident Line on 0300 2000 100.
If there is a risk to life dial 999 immediately.
The weather has also affected electricity supplies, with several thousand customers currently without power across Northern Ireland due to lightning strikes overnight.
NIE Networks’ emergency crews are currently on site assessing damage and restoring supplies.
An NIE statement said, "Before reporting a power cut please check your trip switches, if you are still off supply call 03457 643 643 or report online at nienetworks.co.uk.”