The edition of 2 October 2026
Chivenor has just had its mildest September by night on record, in 49 Septembers of readings going back to 1951, with none between 1959 and 1985, on a figure the publisher still marks provisional.
The whole record for Chivenor or the Met Office file this came from.
13.8
°C
Mean daily minimum at Chivenor, September 2026
The publisher marks this period provisional; it will be revised.
Everything in today's edition comes from one dataset: the Met Office added September 2026 to its historic station files this morning, and nothing else in our patch published. Of the 31 stations reporting the month, 24 recorded a top-ten warmest September by day and 29 a top-ten mildest by night. We name one record and hold the pattern.
Chivenor's figure is provisional, and it leads the next-mildest Septembers, 2006 and 2023, by two tenths of a degree. Its record has a 27-year hole in it, which the sentence names; the record holds on the readings either side. The Met Office finalises station data later; if the record moves when it does, we will say so, on this page and in the corrections log.
For the national picture, the Met Office itself has published September 2026 as provisionally the joint-fourth warmest on record for the UK, from its gridded national series. Our figure is narrower: one station, ranked against every September it has measured.
The August station records reported on 3 September, at Oxford and Heathrow, were not revised this morning and are still provisional.
How this edition was checked
Each claim above was put to a separate agent with only the figures and the publisher’s dataset notes — not the reasoning that chose it — which tried to kill it on the wrong column, the wrong denominator, a series break, a definition change or a revision. Nothing that failed is on this page. The archived copy of each publisher’s file is in this site’s repository under data/weather-stations/raw/2026-10-02/chivenordata.txt.
From the shelf
Whitby and Chivenor set September records on provisional figures
A story we had been watching before today. Developing threads are kept as dossiers with a written trigger — the condition, agreed in advance, that would make them worth publishing — so that what we thought before we knew stays on the record.