Major clearing-up operations are continuing in parts of Counties Tyrone and Fermanagh after flooding damaged homes and businesses.
Several roads remain closed across Northern Ireland.
Firefighters rescued 26 people who were trapped by the adverse weather brought on by Storm Desmond.
One of the worst affected areas was Glenfinn Park housing estate in Strabane, County Tyrone, where 10 people were rescued from their homes.
Northern Ireland assistant chief fire officer Alan Walmsley said: "Firefighters used ladders to bring the residents to safety as well as the assistance of sleds to move the residents to dry land."
He said one firefighter sustained minor injuries while responding to flooding calls.
"The weather forecast is to improve from the previous 24 hours, so hopefully things will stabilise," Mr Walmsley added.
"Motorists are advised there are large areas of standing water resulting in some roads being impassable."
BBC News NI Weather Presenter Cecilia Daly
The effects of Storm Desmond started on Friday afternoon and finished during the early hours of Sunday morning.
The largest rainfall totals were recorded in Fermanagh - Derrylin had 117.8mm which is just under five inches and more than half of this fell in the 24-hour period from 09:00 GMT on Saturday to 09:00 GMT on Sunday.
There were large variations, even within the same county, as Thomastown also in Fermanagh measured just 60.4mm.
Further spells of wet and windy weather are forecast this week but are not expected to have significant impacts. At this stage no weather warnings have been issued.
A Met Office weather warning for heavy rain in Counties Fermanagh, Tyrone, Antrim and Londonderry on Monday afternoon has been cancelled, but rain is still forecast.
On Sunday, flood water damaged clothing stock thought to be worth millions of pounds at the Linen Green shopping complex near Dungannon, County Tyrone.
Stormont's Environment Minister Mark H Durkan has activated emergency payments of £1,000 for householders affected by heavy rainfall and flooding.
Speaking from Paris, where he is attending the climate change conference, he said he hopes to widen access to emergency compensation.
"I'm looking for approval to extend this scheme so that small businesses and, indeed, community facilities and churches can avail of it as well because I know how desperate a situation it is for people," the minister said.
Mr Durkan told BBC Radio Ulster he circulated a paper on his proposals to his ministerial colleagues in the Northern Ireland Executive last week.
Near Enniskillen, only one road is passable into the village of Boho.
The principal of Killyhommon Primary School in Boho, Eileen McKenzie, told BBC Radio Ulster that it will be a challenge for school buses and school meal deliveries to reach the building.
"The area does traditionally flood, but this is unprecedented," Ms McKenzie said.
"I think it is about 25 years since anybody locally has experienced the level of flooding that we've had over this weekend.
"We will try to get in. It will mean a big detour and it will mean the good will of maybe some farmers taking us in in tractors, but we will try to be there because we've always tried to keep the school open regardless."
Rivers Agency chief executive David Porter said the flooding at the Linen Green shopping complex was caused by a blocked culvert grille that caused the water to overflow.
"It was blocked by predominantly bits of trees and there was also some other material - plastic bags and the like," he told BBC Radio Ulster's Good Morning Ulster.
Mr Porter said the agency routinely did "grille runs" and that grilles were cleared across Northern Ireland in preparation.
"We have a considerable multi-agency approach to floods now and there were numerous discussions and lots of preparatory action taking last week between Rivers Agency, Northern Ireland Water and Transport NI who are the responders but also Fire and Rescue and the councils who play an important part in co-ordinating our efforts," he added.
Anita Ross, who owns the shop The Boudoir at the complex, said she had more than £100,000 of stock destroyed which "would not be able to be replaced".
"Whenever I arrived at the Linen Green yesterday there were retailers in floods of tears, because that stock will not be able to be replaced because it is such a short window between now and Christmas," she said.