MET Eireann’s severe weather warning came to pass yesterday with large swathes of the country blanketed in heavy rain leading to localised flooding in Dublin, Wexford, Kilkenny, Tipperary, Waterford, Kildare, Monaghan and Laois. Several major roads became impassable.

The 11am Dublin-Cork train struck debris from a landslide and was partially derailed just south of Portarlington. Iarnrod Eireann said last night that the line is damaged but services from Dublin to Cork, Kerry, Limerick, Galway and Westport will resume today with speed restrictions. A number of windows in the front carriage were broken, but the driver and 310 passengers were unharmed.

Gerald Fleming of Met Eireann said August is likely to be the wettest seen so far: “Dublin airport has already exceeded its average August rainfall. The 159.5mm that has fallen there is about four times the average for this time of year.”

Householders and business owners still recovering from last weekend’s deluge were forced to reassemble makeshift flood defences yesterday.

Tipperary was the worst place affected, with a bridge at Ballynunty impassable and severe flooding in Killenaule, between Fethard and Cashel, and on the N62.

The N7 Dublin-Limerick road at Roscrea was impassable on one side. There was also flooding on the Portlaoise side of Mountrath and in Graiguenamanagh, where torrential rain caused the river to overflow. One resident in the Kilkenny town discovered trout swimming up the main street.

While Met Eireann called it right for yesterday, the service issued only a level-one warning last weekend. Its forecast was at least 36mm of rainfall out.

“To be honest, it was predicted to an extent but not the severity of it,” said Vincent O’Shea of Met Eireann. “Our computers didn’t see 76mm, that’s for sure. We were going for heavy rain and thundery downpours, but we thought it would be more like 30 or 40mm.”

He said the service issues “tiered warnings” when heavy rainfall is expected. The first is given when more than 25mm is forecast. A second, more serious, warning is issued when more than 50mm is expected. This would put emergency services on alert and prompt preparatory work.

“We did put out a warning for 25mm but I have to confess we didn’t for 50mm,” he said. “We thought the rain would come in heavy showers across the midlands as the bad weather moved across the country.

“Instead, it was dumped in a more localised fashion, mainly on Dublin. The incident was what we refer to as a one-in- 150-year event. It was exceptional, a month’s rain in a day.”

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