The results from NWP models these days are truly astounding, but just very occasionally weather services can get caught out even in the short range as were the UKMO, even in their own backyard, by a eighteen hours of heavy rain across Devon. They must have got a bit twitchy about it themselves, because at 0338 UTC they issued an emergency yellow warning for heavy rain. I can’t say just how accurate my rainfall radar estimates are up to 0735 UTC are across the south of Devon, because there are simply no SYNOP observations down there to compare them against, and even the AWS at the Met Office Exeter headquarters has been AWOL for sometime now. I also notice that the rain has spread much further north than was anticipated in the various forecasts I saw for yesterday. If my estimates of extreme totals in excess of 80 mm over Dartmoor are close to accurate, I would have thought this would cause flooding problems in the area this morning as the rain continues, or perhaps the ground is soaking up a lot of it up after the recent dry spell in April.
Here’s a closer look at the estimated totals in more detail.
And here’s a hyetograph for Kingsteignton to show how the rain fell hour by hour.