Indeed, the set up that is causing this latest situation is virtually identical as the one that affected Cumbria a couple of weeks ago. It's all being caused by orographic rainfall where a warm moisture laden airflow that had a long fetch in from the Atlantic is being forced to rise and cool down as it come up against mountainous areas. The end result is condensation producing many hours of heavy hours affecting a particular area, a bit like a giant water logged sponge being wrung dry.
Because this rainfall event is associated with a very slow moving "wavering" weather front dividing the very mild air to the south and colder air over Scotland, it had rained "on the spot" for several hours while little rain fell only a hundred miles to the south and to the north. Even the low pressure centre isn't that particularly deep, it is where there is so much water vapour in that weather front that needed to be released.
I've put together this map using my own graphics set up, hopefully showing a bit more clearly how and why it is happening . . .
The situation is set to improve tomorrow as the weather front move south and decay, but unfortunately it will become problematic again as we go into next week with storm force wind and further heavy rain to affect northern and western parts.
) won't be able to make it tomorrow.
