As heavy downpours have swept across Northern Ireland, there have been warnings of up to 50mm of rain in places.
The Met Office issued a severe flash weather warning for the province, with alerts of heavy thundery showers that were expected to bring up to 15mm of rain within a three-hour period.
In some areas the rainfall could rise to 50mm, it said.
The Met Office also predicted more slow-moving heavy rain this morning, with totals of 20-30mm and local concentrations of up to 50mm.
Northern Ireland Electricity said lightning strikes can damage fuses in the network and promised that its duty incident team is on alert around the clock, 365 days a year.
“We are monitoring the weather to see what happens and prepare to resource up if necessary,” a spokeswoman said.
Forecaster Matt Dobson of Meteogroup said Northern Ireland’s unsettled spell is likely to remain for at least a week. “Today we’re seeing a deep area of low pressure centring somewhere close to the Isle of Man and that will bring plenty of rain and brisk winds as well. It will be an almost autumnal start to the day,” he said.
“The high pressure that kept a few areas across the UK warm and dry have slipped away now, so there is quite a deep area of low pressure for this time of year.
“We expect low-moving heavy showers. Across Northern Ireland there will be one or two bands of showers where you could see a lot of rain in a couple of hours.
“The wind is not too bad, but by the end of tomorrow there could be gusts of over 40mph in exposed areas.
“It’s likely to remain unsettled right into next week. We could see a slightly drier interlude on Saturday, but Sunday, Monday and even Tuesday aren’t looking very good either.”