It caused a scare across the Atlantic, but Humberto is not finished making mischief yet as it helps stir up a storm for Ireland.
Hurricane Humberto rattled the Caribbean and east coast of the United States in recent days before swiftly dwindling from a powerful category five to a puffing category one.
Its remnants are making their way across the Atlantic, however, and mingling with weather systems there to help create the first blast of our storm season.
Storm Amy, due to hit the country on Friday, will move in from the west, bringing strong winds countrywide, with particular focus on northwestern counties.
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Storms can be usual in October, but this one will have quite a warm, almost tropical feel to it. That is because Humberto is not alone squalling around the coastal Americas; it has had the company of Hurricane Imelda.
Liz Walsh of Met Éireann said the two hurricanes have brought warm air from the tropics that has moved out into the Atlantic. There, it meets the colder air that arrives from northern polar regions.
“When you have that kind of temperature difference across the Atlantic, you produce a very strong jet stream, and the jet stream is what gives us our storms,” said Ms Walsh.
“It picks up these low pressures and develops them and swings them towards us.”
The jet stream is a current of fast-moving winds high in the atmosphere that travels from west to east along the meeting point of polar and equatorial air masses.
The greater the contrast between cold and warm temperatures, the more intense the activity within the stream and the more likely it is to generate storms.
Add to it the remnants of a hurricane, with its low-pressure systems carrying swirling cloud and rain that merge with existing Atlantic lows, and the activity becomes more frenzied.
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For the moment, Ireland only need worry about the remains of Humberto, however, as Imelda is forecast to remain as a hurricane and hover around the Caribbean for another few days.
Storm Amy will bring strong winds, but as of Wednesday evening, the Met Éireann wind warning remained at yellow for Friday – level two of the four-stage warning system – with Kerry under an orange rain warning on Thursday.
That’s not to discount the possibility of significant damage and disruption, though.
“With trees in full leaf and because it’s going to hit in the daytime when people are out and about, the impacts may be more severe than what you might normally expect with a yellow wind warning,” said Ms Walsh.
“We could be looking at upgrading to an orange-level wind warning, but certainly not a red.”
With that tropical air still very much part of the mix, temperatures will feel warm despite the storm – significantly higher than the chilly September just past.
Storm Amy’s tail winds will keep Saturday very windy, and Sunday will also be blustery before conditions calm again.
However, there might be another set of warnings if Imelda follows in Humberto’s footsteps.
“Imelda is going to keep going for another few days down near Bermuda, but it will come towards western Europe, and possibly we could be getting some air from that system on Sunday night into Monday morning,” said Ms Walsh.
“But these kind of tropical storms have a way of changing direction and behaving like a pinball machine, so that can be quite a difficult thing to predict this far out.”
Before Storm Amy hits, another yellow warning comes into effect for rain in Connacht, Munster, Donegal, Cavan and Longford.
The heavy downpours are also a gift from the unsettled, hurricane-influenced conditions out in the Atlantic.
