The week started soggy and will end soggy but in between, well it was more like summer again.

When you get a stalled conveyor of subtropical moisture piling into windward upslopes of the West Highlands, you know flooding will be the result.

For us here in the UK, these upper level rivers typically stall, running between troughs to the NW and high to the SE, often connecting the Caribbean or tropical Atlantic with UK. We saw this very setup in November 2009 which produced the UK’s wettest 24 hour period only to be broken by a very similar setup in December 2015.

These setups aren’t particularly common but do happen every so many years, especially when the Atlantic is warm but when they occur, you typically get a months worth of rain within 24 to 48 hours as rainfall is continuous, lasting longer and heavier than normal due to it’s tropical origin.

Moisture stream connecting Caribbean with Cumbria in December 2015.

After 2.5 days of persistent and heavy rainfall, flooding and landslides has brought issues to western Scotland. As much as 9 inches of rain is said to have fallen between Sunday morning and Tuesday afternoon.

https://twitter.com/DaveThroupEA/status/1048858317114802176

These rains were essentially coming off Hurricane Leslie some 2,000 miles to the southwest.

Rest and be Thankful

 

https://twitter.com/BBCScotWeather/status/1049647626877104128

What a difference a mere 100 miles makes! This was Carrbridge at the same time it was pouring still on the West Coast.

Following the big rains, then came the summer warmth.

With a lot of storminess to the west and high pressure to the east but extending in over the UK, we enjoyed plenty of sunshine and stiff southerly winds which drove the temps up up up.

Yesterday’s highs.

24.6C at Northolt was the UK’s warmest October temp since 2011 when it reached an all-time 29.9C.

Now we’re talking about Storm Callum with it’s wind but more concerning is it’s rain and likely ‘multi-day’ rain from another ‘atmospheric river-like’ setup fueled once again from Leslie..

https://twitter.com/SimonLeeWx/status/1050492700238274560

https://twitter.com/RMBwx/status/1050453404231888897

While heavy, persistent and wind driven rains affect a broad area of the UK tomorrow evening into Saturday, the biggest rain totals will be focused on Wales.

With this storm which is exceptionally deep will not only come flooding rainfall and damaging 80+mph wind but also more summer warmth with potential for a record warm Friday night into Saturday morning followed by record warm Saturday afternoon for time of year.

https://twitter.com/SimonOKing/status/1050650390490796037

https://twitter.com/metoffice/status/1050800768230383616

Tags: atmospheric river, atomic bomb cyclone, highland flooding, highland rain, oban, october warmth, record october heat, storm callum, uk october heat, UK Storm