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TD17 is now a tropical storm in open waters of mid-Atlantic. Not heading to US

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I guess all bets are off for just now.

I wonder, what are the chances of this being this season's Hurricane Vince?

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Would have to have some power to reach as far as the mainland, but if I was in the Canaries I would be keeping a very close eye on it. Especially given the last NHC update said they expect it to strengthen further i.e. likely become Hurricane strength.

http://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/091438.shtml

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Heard about the dyslexic American meteorologist? he's been forecasting disruption, devastation and flooding from strong winds to the US due to a spurs centre-forward all autumn.

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025835_5day_cone_no_line_and_wind.png

NHC's cone now has it heading towards Europe. Expected to become Hurricane strength later today.

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13 hours ago, cowdog said:

Would have to have some power to reach as far as the mainland, but if I was in the Canaries I would be keeping a very close eye on it. Especially given the last NHC update said they expect it to strengthen further i.e. likely become Hurricane strength.

http://www.nhc.noaa.gov/text/refresh/MIATCPAT2+shtml/091438.shtml

It needn't bother the canaries thanks... I'm going in a few weeks! 

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2 hours ago, Jo Farrow said:

1010opheliaplot.png

The Azores may get some excitement or some high waves at the very least. 

By the way @Jo Farrow, this storm may help lower the SSTs in that area. How is that likely to impact our winter enemy, the Azores high?

Edited by karyo

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This one is going to be interesting to watch and see how close to Europe it can get before losing intensity. Once it's past the Azores the sea temperatures drop off quite sharply.

 

 

Ophelia.png

sea temps.png

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GFS has weekend temps across the UK between 22'c and 19'c for the south and midlands.

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The Express are already running a Live updates page on Ophelia. Not going to link it as they don't deserve any traffic.

The ramping for this storm is going to be immense if it carries on showing a chance of hitting the UK.

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I seem to recall that 10 years back, Vince formed in this general area... perhaps a bit further east. SSTs weren't that great then, either, but it sustained itself on the back of a nearby system before getting absorbed.

NB: I may recall incorrectly.

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2 hours ago, cowdog said:

The Express are already running a Live updates page on Ophelia. Not going to link it as they don't deserve any traffic.

The ramping for this storm is going to be immense if it carries on showing a chance of hitting the UK.

 

I had a peek, shouldn't but had to, what guff, don't even seem to know where it is going "hot on the heels of Nate" . Very interesting to watch its developments though, strong signal north start of next week

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Eveniing all.

I will be in Ibiza from monday onwards, so I'm really hoping it meanders more east before being picked up by the jet and batters the balearics! 

:) Samos

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Well this is going to be interesting. More and more models actually intensifying this storm as it brushes past Spain and France. October 1987 comes to mind. I seem to recall that one started as a cold low and warm low that combined to make a bang. Well this is one heck of a warm low for these parts. It will need perfect timing and track to match the great storm but if any storm can do it, I'd say this is the one.

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7 hours ago, crimsone said:

I seem to recall that 10 years back, Vince formed in this general area... perhaps a bit further east. SSTs weren't that great then, either, but it sustained itself on the back of a nearby system before getting absorbed.

NB: I may recall incorrectly.

You're right, Vince made landfall in Spain as a tropical depression.

However, Ophelia is forecast to be a hurricane even closer to Europe.. 

024159_5day_cone_no_line_and_wind.png

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Although the gestation was completely different I well remember Carrie in 1957 chiefly because it sank the Pamir near the Azores with loss of 80 Lives. The vessel had been in Falmouth not long before.

Carrie then swung NE into the UK as an extra tropical producing much rain and a storm surge

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windyty takes Ophelia across Ireland and back out into the Atlantic during next week, where it's absorbed by a low before carried back as a post-tropical system. 

Untitled.thumb.jpg.2ecc841d7b7f94f9f439d95d64d1eea1.jpg

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 Its quite an unusual path for tropical storm and forecast modelling will most likely change over the next week, but storms like this can produce a few unpredictable results. Hurricanes Gordon (2006) , Vince 2005, tropical storms Ana (2003), Grace (2009) come to mind.
 The prime concern does have to be for the Azores, but we should also consider what exactly happens when this type of storm goes extra tropical. Based on past observations the storm can become embedded in a frontal system and tropical aspects decay. Unlike storms which go extra tropical mid Atlantic as they lift out, what can happen is that the warm core shrinks in the front and tightens up before breaking up totally. The core moves quite rapidly up the frontal system and in its death throws can just about reach the southern UK bringing localized hurricane force winds. In effect the core tightens, shrinks and its rotation speeds up as it dies with a possibility of producing winds in excess of 100mph.
 In this particular case I don't think this will happen as the tropical storm is not strong enough and the core not warm enough with a result that the core dissipates long before it gets anywhere near the UK. So the prime risk to the UK would be tropical type rainfall and a particularly deep Atlantic low developing as the remnants move towards Iceland. Current modelling would suggest that western Ireland could experience some very strong winds next Monday afternoon and Northern England and Scotland a deluge of rain Monday evening. We should however note that ECMWF and UKMET moved things eastward in the last run.

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Fiddling through all the ensemble members on the ECM, it is clear that southern Ireland is at the greatest risk from Ophelia - there are many members that bring in to the coast with gusts of over 90mph. Also, NW Portugal/Spain is struck on a few ensembles with winds close to hurricane strength. That would be a real shock to this area, as they are not used to even our winter gales. Only a few ensembles get Ophelia close to the UK mainland, and the ones that do see Ophelia already quite weakened, with the very worst ones gusting perhaps to 80mph but no worse.

But I think Ophelia may help energise the whole Atlantic, and there may be disturbances in the days after with potential for quick development.

Interesting times!!

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I'm watching this one with interest. Can anyone explain to me the difference between a tropical and an extra-tropical system? I don't mean definition-wise, rather what it means on the ground, so to speak

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Ophelia appears to have developed a clear eye now on cloud satellite. Not yet at category 1 status though according to latest NHC advisory.

 

Ophelia.png

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This has more similarity to Debbie 1961 than to the October 1987 case, at least so far on most models. That storm likely became extratropical around 48N 15W before racing past western Ireland and causing very strong wind gusts especially around Donegal, Derry and other parts of west Ulster. 

In fact the model trend has been to track Ophelia further west with only a glancing blow for those same areas and later for northwest Scotland, but this trend may reverse closer to the time. 

The difference "on the ground" when a cat-1 hurricane becomes extratropical is mostly academic, the radius of strong winds would likely expand somewhat and the storm will lose its intense inner core and features such as an intact eyewall although remnants will continue to circulate. The exact timing is not that important as locations along the track would likely experience just about the same results especially for these relatively weak eastern Atlantic hurricanes which are somewhat marginally tropical at their best, which is not to say they are weak as far as wind gusts, more in terms of tropical organization. In the western part of the Atlantic basin, an extratropical transition could be much more dramatic in terms of changing the storm's wind field. 

This concept was not really developed in 1961 with Debbie which was analyzed as a hurricane until it was around 53 deg north but by today's standards it was probably extratropical a day earlier than that. 

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