After the heavy rain of 14th August 2023, I set about looking back on days with similar totals in Durham since I started recording here.
The total for 14th August was exactly 30.0 mm, which seems a suitable total to use as a threshold. Here’s what I found:
14th August 2023 30.0mm
17th November 2022 55.7mm
5th October 2021 43.8mm
3rd October 2020 32.7mm
8th June 2019 31.8mm
22nd November 2017 49.3mm
The table shows that 30mm in a day in Durham is roughly a once-a-year event. It is also much more prevalent in the 2nd half of the year, all of the occurrences having been later than June.
Noteable ‘close, but no cigar’ days have been
23rd July 2023 29.3mm
23rd September 2020 28.5mm
28th August 2020 29.8mm
12th June 2020 29.2mm
27th July 2019 28.2mm
20th September 2018 28.2mm
The eventual total for 19-20th October 2023 during Storm Babet was 69.1 mm.
50.3 mm fell on the 20th.
The River Wear rose to 2.62m at Elvet Bridge.