The political division of Ireland may be a very clear one, but both the southern Republic and Northern Ireland will be united in facing the force of Hurricane Ophelia.

Technically, Ophelia will no longer be a hurricane when it strikes Ireland on Monday. It will have been downgraded to a post-tropical cyclone.

That distinction may be lost on those across the island who could be facing sustained wind speeds of 150km/h and gusts of 200km/h.

On Sunday, Ophelia was still a Category 3 hurricane, on the five-point Saffir-Simpson scale, with sustained winds of 185km/h.

After drifting around the central Atlantic over a period of days, Ophelia has now been incorporated into the "conveyor belt" of air ahead of a frontal system further to the west. Consequently, Ophelia is accelerating, heading northeast at around 45km/h.

It is expected that Ophelia will take on frontal characteristics by the time it reaches Ireland on Monday, but the characteristic tight, circular rotation will be in evidence as it then sweeps across the island.

Its arrival will come at a meteorologically significant time, for it will be 30 years to the day since the southern UK was struck by what became known as, The Great Storm.

This frontal depression, without the additional contribution of any post-tropical cyclone, formed well to the southwest of the UK before deepening explosively. It produced a drop in pressure, unlike anything seen in living memory.

The resulting increase in wind speed was spotted too late to give adequate warning and on the night of the 15 and into the 16 October wind gusts of up to 217km/h caused widespread damage and several fatalities.

The storm struck after a mild, wet period across the southern half of the UK. Many trees were still in full leaf.

That, and the unusual wind direction for such strong winds (southeasterly rather than southwesterly) resulted in the very landscape of the region being changed forever, as hundreds of thousands of trees were felled by the winds.

In turn, those trees toppled thousands of power lines, and power was disrupted for a period of several days.

In Ophelia's case, such a scenario is unlikely. The region is familiar with stormy weather, being the first port of call for many Atlantic storms, but structural damage is highly likely across southwestern parts of the Republic.

The Irish Met Service has issued "red" warnings for counties Cork Kerry, Clare, Galway and Mayo.

The warnings mention sustained winds of 80km/h and gusts of 130km/h, but as mentioned above, uncertainty in the development of the storm in the coming hours means that there is the potential for even worse conditions.