Hot spell not going to go quietly…

The latest 06 UTC model run must be showing signs that the breakdown of the current hot spell is not going to be a quiet one.

Figure 1

It looks like the Met Office are still having problems with this new warnings web page of theirs. The map is a great improvement on the old one, but some of the locations plotted on it are blatantly in the wrong place. I reported this to them a couple of weeks ago, and it really should have been fixed by now. At worst its misleading to the general public, at best it just doesn’t look professional, I am amazed that it wasn’t picked up at testing.

Topsy turvy weather

By this time next week this may current heat wave may be just a distant memory, that’s according to the latest GFS forecast, as the British summer monsoon gets into full gear.

Steep thermal gradient this evening across the country

Figure 1

There’s quite a steep thermal gradient across the country this evening, with dewpoints as low as 6.4°C at Stornoway in the northwest, to as high as 19.3°C at Yeovilton in the southwest.

Phew, what a scorcher!

Figure 1

I count 26 stations with 30°C or higher today, and tomorrow, particularly in the southwest it may be even a little hotter again (fig 1). With temperature as high as 32°C, which they’ve been in the London area this afternoon, which could trigger one or two isolated thunderstorms in places.

Figure 2

2017 in Central England – currently joint 4th warmest

2017, continues to move a little higher up the league table of warmest years to date (the 1st Jan to the 18th June), it’s now joint 4th and is within striking distance of both 1990 (0.02°C higher) and 2014 (0.15°C higher), and the way this current hot spell is going it could will go clear as the second warmest start to any year since 2007 before the week is out, in the daily mean temperature record that started in 1772. This is of course based on provisional values for this month from the Met Office.

Figure 1 – Data courtesy of the Met Office


18 June 2017 – diurnal range

This is a listing of the largest diurnal range across the British Isles, well to be precise the difference between the 18-06 minimum and yesterdays 06-18 maximum, I can’t plot the results on a map, so the table will just have to suffice for now (fig 1). Yesterday, Topcliffe in North Yorkshire, tops the list with a range of 18.7°C or 33.7°F.

Figure 1

At the opposite end of the table the minimum and the maximum on the Bealach Na Ba where both 7.7°C (fig 2).

Figure 2

June’s sunshine gets a boost

After a fairly inauspicious start to June 2017, the last few days have really boosted this months sunshine totals, particularly across southern areas. Top of the league at the moment is Jersey with 186.7 hours (average 10.3 hours per day), now there’s a surprise, closely followed by Manston in Kent and Herstmonceux in Sussex.

How’s this thing going to end?

A good degree of consistency between the UKMO and GFS models about how saturday will look at T+120 (figs 1 & 2). How accurate it will be is another thing entirely. Pressure is still forecast to be reasonably high across the south, 1000-500 hPa thicknesses are not far from 564 dm, but there is a fresh to strong westerly flow across the British Isles, with fronts driving in from the west, so things don’t look good for this current hot spell.

Figure 1

Figure 2

Remember the sunshine card?

If you remember ever having to change a sunshine card in a Campbell-Stokes recorder as an observer, then I’m sure that you’ll like this new way of visualising hourly sunshine data from stations across the UK that I’ve dreamed up (fig 1).

Figure 1

I don’t have the luxury of being able to receive minute data from the Met Office network, so the next best bet is to access hourly SYNOP data from OGIMET and put it together in some code and plot a gantt chart, which is exactly what I’ve done here (fig 1). It’s unique as far as my knowledge of visualising systems that don’t have network access to a remote AWS. There is a bit of guesswork about how you assign the hourly amount of sunshine to each hour during the day, I’ve made it so that the program defaults to the end of the hour before noon, and to the start of the hour after noon. The gantt chart format allows you to also see the approximate times of sunrise and sunset for each station. I’m pretty chuffed with the end result which only occurred to me whilst sun bathing in the garden this afternoon!

The other thing that it enables you to do is to watch sunshine total as they increase across the UK in real-time through the day (fig 2).

Figure 2

17 June 2017 – maximum temperatures