Storm Debi yellow weather warning causes flooding across parts of road network in Northern Ireland
Severe rainfall overnight on Sunday has left "several parts of the road network" in Northern Ireland flooding, according to police.
Officers said they are already dealing with a collision on the M1 as Storm Debi hits.
They have advised motorists to "please slow down... allow some extra time for you journey, as there may be surface water and some hazardous conditions".
Meanwhile, power outages have been reported across Ireland as tens of thousands of homes are without electricity.
Spot flooding has been reported in areas of the west coast, including Salthill in Galway.
The PSNI have advised people "not to make unnecessary journeys" and "stay at home where possible" as Storm Debi brings strong winds amid an amber weather warning.
The Met Office said the worst of the weather will hit Counties Down and Armagh from 6am on Monday morning until noon.
Meanwhile a yellow weather warning for wind and rain is in place for the rest of Northern Ireland between 3am on Monday and 2pm.
A number of public transport services in Northern Ireland have been affected due to flood water.
The Republic of Ireland is expected to experience the worst of the storm weather, with a red weather warning issued in east Galway and south Roscommon.
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