Tuesday saw accumulations of 60-80mm, with Malin Head in Co Donegal experiencing over 70mm of rain, according to Met Éireann.
At an on-farm weather station in Newtonstewart, Co Tyrone (pictured), figures from AgriSearch’s GrassCheck programme show that 47.2mm of rain fell.
The rain started to increase in volume from two o’clock on Tuesday, steadily increasing as the evening and night went on.
Flash flooding ensued in parts of Donegal and Derry, with thunderstorms also causing power cuts in some areas.
Stones deposited on farmland by flood waters at Newtownstewart, Co Tyrone.
'Horrendous'
Charles McCandless, a dairy farmer at Malin Head, told the Irish Farmers Journal that Tuesday night’s rain was "horrendous" and that there was a lot of damage done.
Most people kept cows in. We had a few heifers surrounded by water last night, but this morning they were standing along the river bank, all ok.
“There’s a lot of road damage around Carndonagh and some slurry tanks are flooded. The ground is saturated today. People who had reseeding done, them fields will be damaged now.”
Tillage farmer Liam Robb is based near Newtoncunningham in Donegal, where he said over 50mm of rain fell last night.
He only has winter barley cut so far, with no spring crops cut yet.
“It’s going to take a while for the land to dry out. It rained from two until 11 and there was thunder and lightning.”
Buncrana
Henry O’Donnell, a cattle and sheep farmer and Irish Natura and Hill Farmers Association (INHFA) member, said that the rain was extremely bad.
“I was out until 1.30am [on Tuesday night]. I checked the sheep around then and luckily they were in a high corner of the field."
There is huge devastation, I suspect there will be sheep losses for farmers who had land adjacent to rivers.
“Some farmers who has slatted houses near the River Crana brought their cattle to their neighbours sheds. They had to take them out and bring them to higher ground.
“I’ve never seen anything like it. There’s also a lot of damage to farm roadways."
Seamus Campbell, Teagasc adviser for Inishowen, said that a lot of farm roadways have been affected and that slatted sheds are close to flooding or are already flooded.
Yesterday's thundery rain brought 60 - 80mm to parts of Ulster. Malin Head had over 70mm before a thunderstorm cut power to the area. pic.twitter.com/9GrrpNGNbu
— Met Éireann (@MetEireann) August 23, 2017
The latest data from Met Éireann for the full day shows 77mm (3in) of rain fell on Malin Head on Tuesday.
Derry
Reports from farmers with land in low-laying areas surrounding Derry city suggest significant numbers of livestock were lost when the River Faughan burst its banks.
“We had eight pedigree Holstein bull calves in a field on an outfarm at Drumahoe (pictured). When we went up to check them this morning, the field was completely covered and the calves were gone,” Limavady farmer Alastair Craig said.
There was a mudslide on a back road above Eglinton and most roads have been destroyed with the force of the water.
"We had was six acres of straw cut and it was completely washed away,” he said.
Local farmers and agricultural contractors were also helping emergency services on Tuesday night, as residents became stranded on flooded roads.
'Worst rain I've seen in my life'
“It is the worst rain I ever seen in my life. I hope we never see anything like it again,” Eglinton farmer Donald Montgomery said. “The higher ground where we farm wasn’t covered, but fields and roads around Eglinton and Campsie have been completely flooded.
"One neighbour had 13 sheep grazing in a field and they were gone on Wednesday morning,” he said.
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