Most of today’s band of rain has now passed by, leaving us with a total of 7.8mm as I’m typing this at 9.30pm – by no means an exceptional figure, though it may go up a little before midnight. Some eastern parts of the country are seeing a lot more rain than we have.
Today’s rainfall brings the July 2013 total to 16mm, taking this month comfortably out of the “driest month” category. May 2010 was our driest month on record with 12.4mm, and we had just 15.6mm in April 2011. Barring a deluge in the next few days, this month’s rainfall total will be below average but not a record-breaker, despite the hot spell.
A thunderstorm arrived here at about 0245 today and produced a modest 3.2mm of rain. About half of that total fell in the first five minutes of rainfall, between 0250 and 0255, and the rest over the following three hours.
The thunder was nothing exceptional, but there were some very impressive electrical fireworks. Lightning was more or less constant for over an hour – most of it appeared to be cloud-to-cloud rather than ground strikes.
Our rainfall total for this storm was similar to some other weather stations in the region, but convective rain can vary a great deal over a small area. Some local weather stations saw no rain at all, and one station in Bristol recorded over 18mm in an hour.
The Met Office still have warnings in force for heavy rain, but as I type this at 1040 there is nothing for this area on the rainfall radar. The east of the country seems to be getting a bit of a deluge, though.
The high pressure that has given us so much hot and settled weather is moving away to Scandinavia, clearing the way for Atlantic weather systems to move into the UK. The first occluded front reached here just after 5pm, with a sharp switch from a southerly to a westerly wind and an equally sharp drop in temperature – down by 10C in half an hour. There followed more comfortable evening than we have had for a couple of weeks.
There is the potential for some rain, and maybe thunder, overnight but with a confusion of air masses mingling it’s really difficult to predict where or when it may happen.
Yesterday’s temperature record didn’t last long – it was beaten at 16:42 today when we recorded 31.2C, the highest temperature seen here since the weather station was set up in 2007. The reason, once again, was the absence of any cooling on-shore wind. Instead we have had a gentle north-easterly breeze that has had plenty of time to warm up as it crosses the UK.
Today’s daytime (0600-1800) average was just 0.2C below yesterday’s at 25.6C, but still well above the 2009 record. All this on a day when the forecasters said it would be a little less hot – but higher temperatures still are forecast for next week.
One effect of all this heat brings back memories of 1976 (not that the current weather is up to 1976 standards just yet): the 450 foot hill that gives Brent Knoll its name is slowly turning brown.
With no cooling sea breeze this afternoon the temperature here rose briefly to 30.1C at 17:42, setting a new record for this year.
Today also set a new record of 25.8C for the average daytime (0600-1800) temperature, beating the 25.2C recorded in July 2009 and making today the hottest day since the weather station was set up in 2007.
There is more hot weather forecast for next week, so these records may not last long.
Today was a repeat of yesterday as far as temperatures are concerned: whilst some inland weather stations exceeded 30C, coastal areas were a few degrees cooler and the maximum here today was 27.6C. A welcome breeze took the edge off temperatures all day.
The high pressure system that is generating this warm and settled spell is showing no signs of moving on, so we could be basking in the sun for a while longer. We are nearly half way through July, and just 0.6mm of rain has been recorded. With record rainfall in the year to March it seems odd to be thinking of water shortages, but the ground is very dry and not much is growing. We have already moved from a cold spring to a hot summer: if the current weather continues, we could soon complete the switch from deluge to drought.