Drivers are being warned of freak weather conditions which have been hitting the M17/M18 Atlantic motorway corridor between Tuam, Co Galway, and Shannon, Co Clare, as well as sections of the M7 motorway around Roscrea, Co Tipperary.
A number of serious crashes have already been blamed on what Transport Infrastructure Ireland called “narrow bands of hail”, which the Road Safety Authority compared to motorists “suddenly encountering a truck that has spilled a load of ball bearings”.
Met Éireann deputy chief forecaster Joan Blackburn said she herself had experience of the phenomenon. She said she emerged from the western end of the Limerick tunnel, to find the road suddenly “white like Christmas, but covered in compressed ice”.
She said the phenomenon was caused by cumulonimbus clouds coming in off the Atlantic in winter, which cause extremely heavy and sudden downpours and significant hail on the western third of the island.
Ms Blackburn said Met Éireann could forecast for hail but could not say exactly where it would fall.
Exposed
“The M17/M8 from almost Mayo to Clare would be exposed to that and parts of the M7 would be very far west. It is not anyone’s fault, all you can do is slow down,” she said.
Transport Infrastructure Ireland’s Pat Maher said “a driver could be driving on an otherwise perfect road only to hit a section with hail, if the driver breaks, he is in trouble”.
“Hail cannot be treated for. Pre-salting will not prevent hail staying on the road,” Mr Maher said.
In a response to Tipperary TD Alan Kelly, Mr Maher said “issues have become apparent” on the M7 around Birdhill, Nenagh and Roscrea and around Ennis “and points north”.
Hail-related collisions
“Hail showers come in off the west coast. They come across the M18, going from north to south. They come in to points on the M7. The precipitation might fall as rain off the coast but it falls as hail once it comes in. There is hilly terrain, including the Silvermines and Arra Mountains and Slieve Barna,” he said.
He said there were “significant numbers of hail-related collisions between Roscrea and Birdhill” last winter.
Transport Infrastructure Ireland, The Road Safety Authority and Met Éireann said there was little that could be done about the problem, other than asking motorists to be wary and slow down significantly, if there was heavy rain in cold conditions or hail forecast.
