Storm Ciarán

[OhYouBadBadKitten]

This is an early heads up.

Models have consistently been bringing in a deep low pressure for sometime over Wed/Thurs. As is often the case, details are yet to be nailed down, but some of the models are producing some severe gusts - southern coastal winds of up to 90mph and more widespread inland winds of around 60mph. With storms, comes rain too unfortunately. A wobble in the track could take them further north or, keep it all in France. Exactly when and where the low pressure develops will make a big difference in the outcome. More details to follow.

If the storm is named, it will be Storm Ciaran. At that point I'll ask MNHQ to change the title appropriately.

Following. South coast here and have got off lightly this last couple of weeks.

The drains around here are already not coping with the rain

Seems to be changing path and severity very regularly, no one is quite sure yet, forecast for my area is changing every hour with warnings changing from yellow to nothing.

The system behind Ciarán looks like it might fizzle out or head towards France, seems weak at the moment but things could change dramatically in a short period so worth keeping an eye on especially if Ciarán causes chaos

We got the beginning of the hurricane that devastated villages in Northern France last year. Have not long finished repairing the greenhouse....

Oh bother I'm in London due to return Thursday. After hours stood at King's Cross as a result of train and Babet issues a fortnight ago I am slightly concerned I might be doing the same again 😩

Cannot even guess at what to expect on the North Coast of cornwall yet. Really seems like it could be nothing, irritating or where-the-Fuck-is-the-shed

@OhYouBadBadKitten Can you explain what this means re the 950mB?

@ListenLinda Its a measure of the central pressure of the storm. The lower the number, the deeper it is. This can create a tighter gradient (difference between pressure across the system). The tighter the gradient, the higher the wind speed! But there are caveats. The shape of the low pressure matters. Where the centre is in relation to us makes a huge difference as to where gets the winds. Finally, there are other storm features that can bring in severe winds, such as sting jets. I've not seen suggestions of a sting jet.

This is looking like an extremely deep low pressure, but that isn't to say that there will be widespread extreme winds. Nothing suggests that at present. There is a low chance of severe gales (80mph+) in some locations in parts of the SW and perhaps the far SE and some exposed coastal locations. It is likely to be quite disruptive for many. But I do think some are overplaying the storm as it currently stands.

If any of that changes, I will post.

@OhYouBadBadKitten

This is looking like an extremely deep low pressure,

Blimey that is low, but as you say it's the pressure gradient plus other factors that are probably more important than the central pressure when it comes to wind speed.

I am so confused. I have been reading a couple of weather forums and some posts on twitter. Various conflicting opinions with some people saying it has shifted a bit north and others a bit south. When should they get a good handle on the path for this thing?

Plip that's because they are looking at different models and each model is run multiple times a day. Even a small wobble will make a big difference to impacts.

@OhYouBadBadKitten Thank you 😊 i googled it but it didnt make much sense.

To my very amateur eye (OYBBK will probably be along later to correct me on all this!) at the moment, it looks like (starting from 9pm ish tomorrow), the worst of the winds will be all along the south coast/Channel and the worst of the rain, will be in a line across the country from south Wales to N Norfolk up to Yorkshire. It all sort of fizzles out over Thursday night/into Friday.

Gosh, those areas are still flooded from Babet. How awful for the people that have started their clean up operation.

Tipping down this morning. 😢

Rain stopped overnight here but the river is almost over the banks already 😬

There's still significant model disagreement. Remember these models are owned by different organisations by different countries, so the fact that we don't know how severe this will be is not down to meteorologist incompetence, but is simply down to how difficult it is to model the storm accurately.

It still looks like the far SW and far SE are most vulnerable, along with southern coastal areas to a lesser extent. As for elsewhere, scenarios lie between breezy and gales. Rain will continue to be an issue.

I don't want to put timings on to this because of the above.

I think I prefer your wind scale to the Beaufort one @Caerulea

We're not in line with Ciarán. But the forecast is very wet and water levels are already high.

Thank you OYBBK, I understand why you are keen to not put timings on things.

Met Office has just upgraded the South Coast to Amber weather warning for wind - I work outdoors with horses (freelance) and need to drive down a lot of country roads early morning, should I be thinking about taking the day off or is that overkill?

good morning all! School run time winds on south coast in my neck of woods are currently predicted at 72MPH on thurs when we have to be out walking. Eek!

https://www.metoffice.gov.uk/weather/warnings-and-advice/uk-warnings#?date=2023-11-02 where do you live littlebitpyscho? If in an amber warning area then I would not travel unless essential.

gratedbluecheese If this warning still remains by Thursday morning and you are in an area that will see those sort of wind speeds, then you should not be walking to school.

I seem to be under about five warnings on that map 🤔

Guess it's going to be wet and windy then

A useful graphic from the met office. Note that there is a widespread yellow warning out for both wind and rain. The rain warning starts at 6pm tomorrow, the wind warning 9pm, both through to the end of day on Thursday.