Ex Ts Katia To Hit The UK - Chat Thread

[weatherobsuk]

It irks me when people say 'it can't be a Hurricane because of SSTs', the NHC have came out with the forecast discussion saying SSTs will be maintaining the Hurricanes intensity into the North Atlantic, with forecast Hurricane winds crossing well up to the Western Isles & Faeroe Isles on the models up to this point. Personally to me if its come from a Hurricane, if it acts like a Hurricane, and the NHC label it a Hurricane, then it is. No doubt the Met Office however will turn a blind eye like with past extratopical Hurricanes to cross the UK (cold core, and warm) and shrug it off merely as a 'windy day'

[chionomaniac]

Katia is definately not be tropical when it gets near our shores all analysis and forecasts show a distinct temperature gradient with a classic wedge causing the winds so very much baroclinic in nature. IMO the extra tropical transition will either have happened or largely have happened. Phase analysis from UKMET and GFS 06Z shows the differences as to why METO is not handling this very well at all. UK MET initialises Katia at below hurricane strength due to it's resolution this obviously has knock on impacts as to when the storm gets into the NW Atlantic as it has far less energy. GFS brings a swave of hurricane strength 925 winds to northern England. Where the METO might be more accurate is the general path of Katia which could well be further south of the GFS set up. ATM we are probably looking at sustained winds of 70-80 mph and gusts to 90mph for exposed areas for Scotland and Ireland and gusts to 60mph further south. A point I would make is that we have only had a single recon into Katia due to this very little information is known as to the wind radia, strengths, or the size of the low pressure system. Far less is known than with any normal tropical storm. How this transfers from tropical to ex tropical to baroclinic is guess work. Due to these factors the models will not have a good steer on path or intensity until T72 to T48.

Very much agree, Iceberg. The critical period is likely to be around Saturday when the storms enters the jet stream and will continue to be driven by baroclinic temperature gradients.

[shedhead]

It irks me when people say 'it can't be a Hurricane because of SSTs', the NHC have came out with the forecast discussion saying SSTs will be maintaining the Hurricanes intensity into the North Atlantic, with forecast Hurricane winds crossing well up to the Western Isles & Faeroe Isles on the models up to this point. Personally to me if its come from a Hurricane, if it acts like a Hurricane, and the NHC label it a Hurricane, then it is. No doubt the Met Office however will turn a blind eye like with past extratopical Hurricanes to cross the UK (cold core, and warm) and shrug it off merely as a 'windy day'

Which in effect is what it's likely to be, at least for some.

[weatherobsuk]

"Earlier on today, apparently, a woman rang the BBC and said she heard there was a Hurricane on the way... well, if you're watching, don't worry, there isn't!"

[Shadow]

"Earlier on today, apparently, a woman rang the BBC and said she heard there was a Hurricane on the way... well, if you're watching, don't worry, there isn't!"

[Iceaxecrampon]

"Earlier on today, apparently, a woman rang the BBC and said she heard there was a Hurricane on the way... well, if you're watching, don't worry, there isn't!"

.........remember it well - is Mr F availiable for comment?

[NorthNorfolkWeather]

I just have to say that, whatever the final course of this Hurricane, the way that Chio, Iceberg, Coast and others help explain what's likely to happen just exemplifies to me why Netweather is the best set of forums around.

On the actual track it will take, I just hope that we have no severe problems, I would be interested in how low the pressure goes when it's coming across the Atlantic

[Harry]

Bomb anyone?

[Radiating Dendrite]

I just have to say that, whatever the final course of this Hurricane, the way that Chio, Iceberg, Coast and others help explain what's likely to happen just exemplifies to me why Netweather is the best set of forums around.

On the actual track it will take, I just hope that we have no severe problems, I would be interested in how low the pressure goes when it's coming across the Atlantic

Well it was down under 940mb on the GFS yesterday. It has since filled a bit (well has been predicted too). As has been mentioned above, the interaction with the Jet Stream is the critical part, if this is good then it will bomb!

Bomb anyone?

Could be!

[Zenarcher]

I've been watching this closely over the last 2 days and being in it's path according to the latest GFS run it's something I need to watch. Forecasts for me on Monday morning 57mph with 77mph gusts at the moment.

06z run,

Close up on the UK,

The ensemble run that's just out has moved the low further out away from the UK,

[AderynCoch]

"Earlier on today, apparently, a woman rang the BBC and said she heard there was a Hurricane on the way... well, if you're watching, don't worry, there isn't!"

...and there wasn't, even despite them greatly underestimating the strength of the storm that did arrive.

[loopydreamer]

....hmmm.. the west side of the country could definetly see some damage in my opinion, especially N/W scotland but how will this effect my location im wondering?

[Paul]

Nick has updated his daily look at Katia

http://www.netweather.tv/index.cgi?action=news;storyid=792;sess=

[weatherobsuk]

Katia just needs a few degree's shifting with the jetstreak south, and the forecast +120hr out will have those +60mph sustained winds coming across Northern parts of Ireland and the UK into Monday. Not ideal for the start of a working week aswell as the winds hampering transatlantic routes whatever impact along the Scottish coastline it takes, be it further to the North or South. Luckily the sea swell heights aren't as dire as they were forecasting a few days ago, but a +20ft swell is still pretty bad for shipping planning to be out there, and no doubt watching these models by the hour.

[Chris D]

New advisory out from the NHC, and Katia's track has shifted significantly further south as a response to 12z guidance shifting closer to the UK by +120hrs.

http://www.nhc.noaa....2.shtml?5-daynl

Edited September 7, 2011 by chris93

[loopydreamer]

New advisory out from the NHC, and "Ex" Katia's track has shifted significantly further south as a response to 12z guidance shifting closer to the UK by +120hrs.

jeez that sounds slightly worrying? exciting? havent decided yet!

[Chris D]

jeez that sounds slightly worrying? exciting? havent decided yet!

We've still got another few shifts to the south until we should be really concerned yet

But, the NW of Scotland looks like it could get battered if this run turns out to be right anyway.

Edited September 7, 2011 by chris93

[Radiating Dendrite]

jeez that sounds slightly worrying? exciting? havent decided yet!

In Kent you will be fine. Probably just a windy day.

I think the west and north need to worry.........if it continues to develop.

[Harry]

In Kent you will be fine. Probably just a windy day. I think the west and north need to worry.........if it continues to develop.

Not entirely sure with that RD....inland Kent you might be fine, but coastal Kent potentially a different kettle of fish entirely! The entire Channel coastline is exposed to strong winds, particularly the further East you head as the 'corridor' if you will narrows.

Nearer the time will be interesting as forecasts will start considering the tides and so on and whether coastal flooding remains a distinct possibility.

[Radiating Dendrite]

Not entirely sure with that RD....inland Kent you might be fine, but coastal Kent potentially a different kettle of fish entirely! The entire Channel coastline is exposed to strong winds, particularly the further East you head as the 'corridor' if you will narrows.

Nearer the time will be interesting as forecasts will start considering the tides and so on and whether coastal flooding remains a distinct possibility.

Maybe, but I think Chatham is far enough inland.

I think this will end up a Western Isles event, not one for the Channel Coastline.

[Iceberg]

This update from the nhc will be based on the 06z models as the 12z won't have been out in time.

[Chris D]

This update from the nhc will be based on the 06z models as the 12z won't have been out in time.

True. The "Valid time" on this site must be wrong, apologies.

http://moe.met.fsu.edu/~acevans/models/

[loopydreamer]

i agree it will just be windy here in chatham, but coastal areas, west and north will be another story if the remnants of katia get closer to the UK! I have to say that im enjoying reading all your posts and have always been rather fascinated by hurricanes since the night i witnessed (1987) whilst living in tunbridge wells. So will be glued to this thread to see what path katia takes!

[glasgow-guy]

nw forecast models for the Glasgow area for Gusts of up to 55mph late afternoon Monday it will be interesting to watch how katia tracks closer weather there will be a increase in speed or the latter

[loopydreamer]

True. The "Valid time" on this site must be wrong, apologies.

http://moe.met.fsu.e...acevans/models/

lol! okay! ... tbh it will probably end up far enough away from the UK and just affect the north! its a bit of a waiting game atm!