Yesterday's storm approached Ireland as a deep depression from the south, skirting past Portugal a few days ago as it moved northwards towards the Cork and Kerry coastline.
It was exceptionally deep by any standards. The central pressure seems to have been in the region of 950 hectopascals, and when you consider that the lowest barometric pressure ever recorded in Ireland was 925 hPa - and that well over 100 years ago - it indicates a very active little storm indeed.
It follows in a proud tradition of October storms. October is not, in general, the stormiest month of the year in Ireland - December and January, on average, are worse - but there have been many memorable ones. Readers of "Weather Eye" in The Irish Times a few days ago will recall that it was the havoc and the extensive loss of life caused by a severe storm in late October 1859 that resulted in the routine production of gale warnings and shipping forecasts for the first time on these islands. And who will forget the famous October Storm of 1987? That was the one which laid waste the entire south of England, and brought the wrath of an angry nation down on the head of poor Michael Fish, who had assured everyone the night before in his television weather forecast that no hurricane was on the way.
So, severe as it was, there was nothing apocalyptic about yesterday's event, and it must also be said that on this occasion the entire weather sequence seems to have been predicted very accurately, and several days in advance.
When the clearing up is done, flooding rather than exceptional winds may prove to have done the more damage, and in this context the timing of the storm has been unfortunate.
Firstly, it has arrived after a very wet period, with many parts of the country, notably the southeast, having already experienced between 25 and 50 per cent more than their usual October rainfall. The extra 50 to 80mm of rain produced by the storm - this in itself approaching the normal rainfall for a full month - have been deposited on an already sodden landscape; it is not too surprising that the country's drainage systems and waterways have found it hard to cope.
And secondly, there was a full moon yesterday.
High tides are at their highest at full moon, when the Sun and Moon, on opposite sides of the Earth, work together to produce very high waters - the so called "spring tides". When spring tides coincide with rough seas, and very strong on-shore winds pile the waters high against the coastline and impede the outflow from the rivers, coastal flooding is a frequent consequence.
Many urban districts in the south and east of Ireland suffer problems of this kind from time to time, as at present, whenever all these factors coincide.
And another unfortunate feature of this particular storm is its longevity.
Normally when a storm approaches Ireland, it moves rapidly northeastwards close to, or across, the country; it may be bad, but the worst of the weather lasts for a mere 12 hours or thereabouts. In this case, however, the depression stalled, and at the time of writing seems set to live out its life wobbling adjacent to our southern coast.