Swanley Town Council

**Operational Impact Warning** 20th to 21st September 23rd to 24th September

Storm Bronagh will bring a spell of windy weather across southeast England tonight which could lead to damaged or fallen trees, disruption to transport, difficult driving conditions and the possibility of power outages. Further strong winds could occur on Sunday.

Warnings issued:

– Yellow WIND Warning (Low Likelihood of Medium Impacts) valid 1800 on Thursday 20th September to 0900 on Friday 21st September 2018.

– Yellow WIND Warning (Very Low Likelihood of Medium Impacts) valid 0900 on Sunday 23rd September to 0900 on Monday 24th September 2018.

Thursday:

An area of low pressure, now named as Storm Bronagh, is forecast to deepen and move northeast across Wales and northern parts of England on Thursday to bring a spell of wet and windy weather across Southeast England this evening and overnight.

There are still a few uncertainties around the depth of the low and its associated winds however some impacts are expected.

Today will be mainly cloudy with outbreaks of rain across more northern areas of Southeast England, such as the Thames Valley, but this is expected to clear to the north to give a mainly dry afternoon.  

However, further outbreaks of locally heavy rain are expected to spread east on a cold front this evening and overnight.  

As the low pressure moves east the south-westerly wind will strengthen with gusts of 40-50 mph likely around the coast and in places inland. 

However, there is a small chance that stronger winds may develop in places especially on the passage of the cold front with the potential to see gusts of 60-65 mph in places, more especially across more eastern areas.  

These wind speeds could lead to isolated damage to property and damaged or fallen trees bringing a risk of power outages and disruption to transport. 

We could also see large waves along the coast.

With the leaves still on the trees, impacts may be higher than we would normally see with these wind strengths.

The wind will turn west to north-westerly behind the front and will gradually ease.

The Met Office have issued a Yellow WIND Warning (Low Likelihood of Medium Impacts) to cover the risk of seeing impacts from Storm Bronagh.

Many of the impacts are likely to be in the low impact category but there is a low risk of medium impacts.  

The warning will be kept under review and updates sent as required.

Friday / Saturday:

Friday will be a breezy day with a mix of sunshine and showers with wind gusts of 35-40 mph isolated 45 mph at times, easing during the evening. 

Saturday will start dry and bright but cloud and rain is expected to move east across all areas late morning and through the afternoon.

Saturday night / Sunday:

An area of low pressure is expected to move east on Saturday night and Sunday but how deep it becomes and what track it will take is very uncertain.

However, there is the potential for a wet and windy spell of weather across Southeast England on Sunday.  

It is not possible to put too much detail on this at the moment but there is the potential for strong winds and heavy rain during Sunday before clearing to the east.

The forecast will be monitored carefully and updates sent as the forecast becomes clearer.

The low pressure area clears to the east late Sunday with the wind easing and high pressure developing for Monday leading to more settled weather.

The Met Office have issued a Yellow WIND Warning (Very Low Likelihood of Medium Impacts) to cover the risk of seeing impacts during Sunday. 

KCC Action: KCC HT&W will continue to monitor and take action as and when required