Wednesday, October 02, 2019

Hurricane Lorenzo: October 1, Update A

Mr. Lorenzo and his tropical storm conditions are now pretty much at the Azores, which are getting more of the windy weather than the rainy weather...

He is at 39.1N, 32.7W, heading NE at a really really rapid 40mph. Wind speeds are estimated to be 100mph, central pressure is 960mb. This makes him officially a weak cat 2 storm (cat 2 range: 95-110mph). 

However, there isn't a good eye (as you can see in the satellite imagery above) and his convection is very weak for a cat 2, so you wouldn't be mistaken in thinking he's not really a classic cat 2 storm - because he's not. His wind speed is actually weaker, but because he is moving forward at that ridiculously fast speed, the effective winds being felt are a lot stronger! This is why they have maintained his cat 2 status. 

There are a couple of unusual things about this Lorenzo. First, his forward speed. This is something we usually see with a storm that has been caught up in a low pressure front. The circulation in the lower levels of the troposphere are beginning to shift towards the signal we see with a front, but his circulation in the upper troposphere still has the circulation pattern of a hurricane, so I would say he is still very much a hurricane (for today at least).

Second, he is over cold water - colder than 26 deg C at the surface. This is why his convection is not very strong. But it also means he isn't going to be getting much energy from underlying warm water - again, something we see with a extratropical storm, not a tropical storm. So overall, I'd say he is transitioning from one type of storm to the other.  

The NHC maintain his hurricane status until Thursday - because of his wind speeds as he races across the north Atlantic.

As for his track... well...hmm...

Lorenzo says, "I must tell thee all. She hath directed..." (Merchant of Venice). Oh how true. Yesterday I did mention he was going to the Ireland/UK area to weigh in on Brexit, and where better than to the seat of it all - London...? It is, after all, October 2019... 

What does this mean for Ireland and the UK? 

Well, Ireland should be getting ready for a storm on Thursday as there's a possibility that winds will be at strong Tropical Storm level/weak cat 1 hurricane still - around 70-75mph. This sort of storm at those latitudes can result in trees being uprooted etc. so be prepared. The good news is that there is some wind shear ahead of him, so, in addition to the cold water, he should weaken a bit before getting to Ireland. It's tricky to say how much, but he won't grow. A big issue will be the waves on the west coast - expect them to be ginormous (and move away from the coast if you are in an area which gets coastal erosion in winter storms)! 

After crossing Ireland, and once in England, he will still have some decent wind and maybe a little rain (because it rains with every gust over there and I don't think they've had enough this week). This will still be at Tropical Storm level (or strong gale force if you like) - maybe with winds close to 55-65mph - it'll be a very blustery day on Friday (uh-oh, I feel a song coming on...):

Hum dum dum dum ditty dum
Hum dum dum
Oh, the wind is lashing lustily
And the trees are thrashing thrustily
And the leaves are rustling gustily
So it's rather safe to say
That it seems that it may turn out to be 
It feels that it will undoubtedly 
It looks like a rather blustery day...

(from a very famous bear).

Remember, he could go anywhere in that white cone of uncertainty - so you should all be prepared. I'd stay at home on those days with a lovely cup of tea, if you can! (and maybe stock up on a few candles, just in case). 

More tomorrow! 
Ciao for now,

Twitter: jyovianstorm
These remarks are just what I think/see regarding tropical storms. If you are making an evacuation decision, please heed your local emergency management and the National Hurricane Center's official forecast. This is not an official forecast.

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