A yellow weather warning will stay in place until 11.45pm on Saturday.The heaviest rain is expected to fall in counties Antrim, Down, and parts of Londonderry and Armagh with up to 50mm of rain in 12 hours.A Met spokesperson stated: "Rain is expected to persist until late evening bringing the risk of disruption to travel and outdoor activities."The most rainfall recorded so far is in Ballypatrick Forest, Co Antrim, where 40.8mm fell in six hours.A yellow Met Office alert warns of severe or hazardous weather which has the potential to cause danger to life or widespread disruption.Police are appealing to all motorists to exercise caution due to surface water flooding on many roads.A PSNI spokesperson said: "Drivers should slow down, use dipped headlights and keep a safe distance to the car in front."Motorists are advised to exercise caution following reports of heavy flooding at the Glenshesk Road, Armoy area this afternoon.— PSNI (@PoliceServiceNI) August 2, 2014In north Antrim, police are also advising motorists to exercise extreme caution on roads between Ballycastle and Armoy due to landslides in the Hillside Road/Lagge Road, and heavy flooding on Glenshesk Road.Elsewhere in the Glens of Antrim, there have been landslides on Glen Road, Glenariff and the Coast Road, which is closed between Waterfoot and Carnlough.In Ballymoney, there has been a land slippage on Altarichard Road.Aughnabrack Road, Templepatrick is currently closed due to flooding. Motorists are being advised to seek an alternative route.A statement from the Department of Regional Development said that north Down and Ards had been worst affected.Meanwhile, MET Éireann has issued an orange status warning for severe rain in Leinster, and the the border counties of Cavan and Monaghan after heavy rainfall overnight.Orange is the second highest warning given out in the Republic."A further 40 to 60mm of rain is likely to accumulate up to 6.00am, Sunday 3rd August, and may cause flooding problems locally," a statement from MET Éireann said.Elsewhere, a number of roads have been closed in Dublin due to flooding.