Atlantic Super Storm? Maybe…

A hypothetical swell becomes a virtual reality? Maybe...

Another red blob stoking a storm of internet interest. We shared a chart of this storm yesterday on Facebook and it seems to have taken on a life of its own, marching across the social sphere. So how likely is it to actually happen?

Update 13th Jan 2013

After attempting to pour at least a little cold water on this one the alternative atmospheric models (principally the UKMO and ECMWF) are moving to a prediction broadly in line with this one – a deep low covering the majority of the North Atlantic around Saturday 19th. While there is still variation (and a 100% model agreement isn’t the same as a 100% guarantee) it increases our confidence at this range in a powerful swell around the 22nd January for West facing Atlantic coasts. Your local forecast updates every six hours with the latest information.

I’ve left the original post as is below:

North Atlantic lows are hardly unusual this time of year – even of the magnitude hinted at by these charts – and we’ve spoken before about this being one of the most basic tests you can use to evaluate the likelihood of a given forecast coming to pass. But it’s not the only test – and in this instance there are still a number of factors that suggest you might not need to fuel the ski or wax your rhino chaser just yet.

Other Models

The GFS model we use primarily on the MSW site has been quite keen on this storm for a while now. Certainly going back 48hrs or so there have been repeated runs suggesting a deep and large low pressure system around the 18-20th of the month resulting from a particularly strong forecasted Jet stream. However the GFS Ensemble model – which attempts to explain some of the uncertainty resulting from our inability to start the model with perfectly accurate observed conditions – is still showing a range of possible scenarios – in fact there’s very little pattern at all at the 192hr range we’re talking about which explains how volatile the model is in this particular scenario.

Beyond just this model we can check others at this range – and here the story is again one of caution. The reliable ECMWF shows a deep low in the Labrador sea at this stage, but nothing that resembles this chart. In fact quite the opposite – with strong high pressure blocking over Europe.

Bottom Line

We’re too far out to tell on this one – everything agreeing doesn’t make it happen – the favourite doesn’t always win the race. But this one is a longer odds outsider. That said it’s January in the North Atlantic – there will be a stack more storms and big swells to come…