UPDATE: Friday November 4: Over the past 48 hours, ex-hurricane Martin moved out of tropical waters into the open North Atlantic, and merged with another storm, that formed off the coast of Canada. The result? A tight, powerful storm currently about 800 miles southwest of Cape Farewell and moving east towards Ireland. The central pressure, at less than 940 mb, is more like a mid-winter storm than one occurring this time of year.
It cometh! Our North Atlantic swell chart from Wednesday November 1 through to Sunday November 6.
The broad area of storm-force winds to the south of the system is generating some large, long-period swell, which will continue to grow as the windfield moves east. Open-ocean wave heights around midday Saturday are expected to be more than 40 feet. The storm then weakens as it moves northeast, becoming a complex, multi-centred system west of Scotland by late Sunday.
Two preliminary pulses of swell move ahead of the main bulk of the swell, arriving at westerly exposures today and Saturday, before the really solid swell arrives on Sunday, continuing through Monday.
In northern and mid areas, conditions won’t be too favourable, with strong west or southwest winds, but in southern areas such as France, Spain and Portugal, there could be some epic big, long-period swell with light offshore winds. Spots that have local focusing effects and come into their own with long periods (such as the Spanish reefs) will probably be much bigger than surrounding spots. Nazaré will be huge of course, but once again the WNW swell direction isn’t ideal.
We'll keep you updated throughout!
EARLIER, Wednesday November 1: Right now, there are waves right across Europe's western flank. Two duelling low pressure systems are generating a whole load of different conditions across that stretch of coast. But everyone's head space is elsewhere. What's happening today is a warm up session, a need to feel things through, to check equipment, because what's coming on Sunday evening and Monday morning may just be the season opening XXL session. And we're ready for it.
There's a disturbance in the middle of the North Atlantic, in the shape of Tropical Storm Martin, which is currently located about half way between the Azores and the US east coast and is moving slowly ENE. With maximum sustained winds of around 70 mph, the system is at the point of becoming a hurricane (FYI, it needs to be 74mhp for a hurricane).
Live cam: Nazare
“Over the next couple of days, Martin is expected to turn towards the northeast and accelerate rapidly,” says MSW forecaster Tony Butt. “It will then merge with a strong mid-latitude trough that is currently moving off the coast of Canada.
“The two systems merging together will form a really powerful extra-tropical system by late Friday, which will expand in area and arc around towards the east. It is this easterly movement combined with the large area of storm-force winds that will generate a pulse of very large swell.”
How big? Well, we're talking XL western Europe, like France and Portugal and more after the weekend. And even before then, the likes of Mundaka could get a licking on Thursday and Friday.
“After that though, the system does weaken gradually as it moves towards northwest Europe, expected just northwest if Ireland by late Sunday,” said Tony. “The swell moves slightly ahead of the storm itself, arriving in Ireland by Saturday and then in Galicia, Spain, Portugal and France, in that order, on Sunday. Conditions will be clean along the northern Spanish coast, with light to moderate south or southwest winds, and will also be clean in Portugal, with light variable winds or light southerlies.
Our North Atlantic swell chart from November 2 through to November 7. Lots happening!
“This is a great example of tropical storm merging with a mid-latitude depression – something that can only happen when the conditions for the formation of these two things coincide, ie warm water around the Caribbean and further north, and a healthy upper airstream across northern latitudes. There is usually only a small margin during the transition period between summer and autumn, when this happens.”
And so, we here is your early warning and alert to keep an eye on your local conditions for western Europe, because with that combo, and this time of year, we could be about to see something amazing. Stay tuned, we'll keep you posted.