It’s interesting looking at the GFS model data at the moment; the jetstream is stuck in a big almost-stationary loop way to the north of the UK, trapping a big area of high pressure over the UK and keeping the hot dry weather over us. It looks like it won’t start shifting down south of us again until towards the end of the month, when it will push storm fronts up towards us from France. We’re definitely in a heatwave, here in the UK.
This is the 12th day with temperatures over a minimum of 28°C, making it the longest hot spell since 2006 (I was pregnant with Freda back then; it was NOT fun).
Rainfall for the UK from 1-15 July was 9.2 mm. At this stage we would expect to have seen about 48 % of the full month average, however we have only seen 12 %. We have seen less than 5 mm widely across much of England and parts of eastern Scotland (many locations with only 1 or 2 mm). To put this in context, the driest July on record across the UK was in 1955 when there was 30.6 mm of rain. With only 9 mm of rain so far in the UK this July, this is likely to be a very dry month but – with two weeks to go – it’s too early to say where it will end up in the national series dating back to 1910. I’ve seen newspaper reports claiming it’s the driest July in 247 years; I’m presuming they’re basing this on the England & Wales precipitation records that go back to 1766. The driest July on record was 1825 which had just 8mm, but although England & Wales has seen only 4mm thus far it’s still a bit early to be claiming records just yet.
With regards to sunshine hours, 1955 is the sunniest July on record with 256 hours of sunshine, with 2006 close behind with 253 hours. Up to the 15th we have seen 132 hours of sunshine across the UK, which is 77 % of the full month average. We would have expected to have seen about 48% at this point in an ‘average’ month, but it’s too early to say if we’ll beat 1955.
The other big year that people talk about when referring to heatwaves in the UK is 1976, but 1975 was actually hotter overall and summer 1975 extended from April to October (the 1976 heatwave had hotter temperatures but only lasted from June till September). This summer has started too late to match 1975, but I think we could well see it equal 1976. As to exceed it? It’s really too early to tell. But I’ll be buying a few summer school dresses for Freda for the start of the new term in September – and I suspect she’ll get a lot of wear out of them!