Several parts of London had rainfall accumulations of over 2″ overnight as a band of thundery rain clipped the southeast of the country. The heaviest rain was confined to one thin strip running SW-NE across London and another massive band of 75-100 mm accumulations that ran along the central spine of the English Channel. My estimates from 15 minute weather radar reveal that the wettest location was Stepney which had 62.4 mm in six and a half hours . A very well forecast event by the Met Office, who picked it up early and had all the warnings in place, but was lacking the precise details, as the heaviest band of rain ran up across London rather than the coastal strip of Sussex and Kent which I heard in the BBC forecasts. This may not be the end of it either as another band of thundery rain is forecast for later today.
Farnborough in Hampshire was the wettest place overnight in the 18-06 totals as reported in the 06 hr UTC observations with 45 mm, followed closely by St James Park with 43 mm. My estimate of 44.6 mm for the city of London was very close to the 43 mm recorded their.
A very muggy night in the southeast despite all the heavy rain, with temperatures at St James park falling no lower than 18.1°C.
The Observer at Odiham needs a medal for these overnight observations. I’m not sure that I would have reported a heavy shower for four hours solid. It takes me back to when I queried an old observer about a shower that had run on for hours, because I was under the impression that a shower should last no longer than an hour, but what do I know. I do know that they have laser cloudbase recorders these days but five layers (possibly more) of low cloud is pushing it a bit I would have thought, nevertheless a very fine effort!
After my posting yesterday and just for completeness we finally finished up with 52.1 mm (0000-0000 UTC) of rain yesterday from my automatic weather station [AWS] in Bradninch in mid-Devon, making it the wettest day here for a long time possibly since 2004 when I installed the Vantage Pro AWS. I know I’m a complete weather and climate nut, and I should know what the wettest day is from my own records, but sadly I don’t, and why that probably only a psychoanalyst can fully answer. It maybe to do with ‘cobbler’s children have no shoes’ syndrome but I digress, and to be honest who cares anyway?
The 0600-0600 estimates that I make from the weather radar images do have a few red 50-75 mm coloured pixels to the west of the town so I was in the ballpark, but we weren’t the wettest place in Devon, looking at the list Exeter airport had 41.1 mm with a few yellow pixels on the accumulations map.
And finally, just for the sake of posterity here’s the rainfall intensity chart for yesterday afternoon.
Until very recently it had been a very dry month in our part of mid-Devon. That all changed this afternoon when we had a series of heavy showers and thunderstorms with some intense periods of rain. My Automatic Weather Station [AWS] has recorded 30.8 mm until now (1530 UTC) and that’s backed up by the accumulations that I’ve estimated from the Met Office weather radars 15 minute frames. Here are the totals since 06 UTC today across the British Isles.
We can’t compete with the likes of the mountain Bidein a’ Ghlas Thuill in Torridon in the northwest highlands of Scotland (72.2 mm), or come to that the Oxfordshire golf club (38.8 mm), but #30 in the table’s with 30.8mm of rain in less than 4 hours is pretty respectable, and very close to what my AWS actually recorded.