What’s Lorenzo going to do? Risk of UK Severe Gales later this week

Hurricane Lorenzo has been “in and out” of the headlines recently. It became a category 5 storm in the Atlantic a few days ago, and is currently a strong category 2 hurricane with sustained winds of 105mph. It’s unusually far east, which means us in the UK have to be “on watch”. It’s rare hurricanes appear so far east in the Atlantic.

So what is the forecast? Well, very confused, to say the least. This is a rare situation, and as a result computer models don’t have all that much experience in dealing with it, so the forecast is, well, pretty confused. However, there are a few options on the table. One is that Lorenzo could “hit” the UK, effectively, bringing with it very strong winds and some heavy rain. Thursday to Saturday of this week is the watch period for potential UK impacts. The most “at risk” areas are western Britain and Ireland, as the storm will retain more of it’s energy here, if it does hit the country. As it passes over western Britain it will have “used up” a lot of it’s energy and as a result will become a weaker system as it moves further east.

That however, is not to say, that it does not pose a risk. Many computer models (used in weather forecasting) suggest that many areas could be affected. The chart below shows the GFS’ (a computer model) predictions for the upcoming Friday. As you can see, Lorenzo, is quite close to the UK. It’s quite windy widely in the west, however the very strong winds (60-70mph) are restricted to the west of Ireland.

Can you make out the eye of the storm near the north west coast of Ireland on the chart above?

Lorenzo could also produce a lot of heavy rainfall. Given the ground is so saturated right now, with a high volume of flood warnings in force, it wont take that much rainfall to result in flooding issues. Another issue could well be storm surge, especially if associated with high tide, across western coastal areas.

Also, as mentioned, a fair few computer models have Lorenzo “sat out to sea” and not really affecting the UK to a great deal. This German computer weather model (ICON) is showing exactly that. The system being around 100 miles west of Ireland, however still being pretty windy!

Charts are courtesy of Meteociel.fr. So to summarize, there is a risk of strong winds, heavy rain and possibly storm surge, however we’re still “too far out” to be decisive about what this storm will do, so my advice is be prepared and just stay tuned to forecasts and see if they change. There is a lot of uncertainty, but Thursday to Saturday of this week is the watch period.