At the Royal Welsh Show attendance records were broken and on Thursday in Cardiff the temperature soared to 28 Celsius making it the hottest day of the year so far in the capital.

Since then it has turned cooler and fresher with lower humidity. Daytime temperatures this week between16 to 21 Celsius, 61 to 70 Fahrenheit, which is around average or a little below.

Low pressure near Ireland will also bring us some rain and fresh to strong winds but good news for our wave starved surfers this summer.

Thursday and Friday will be brighter with a mixture of sunshine and scattered showers.

The air will be unstable so the showers could be heavy in places with hail and thunder.

The weekend will continue rather cool and changeable with showers and sunny spells.

So not the best of summer weather this week but at least the pollen count will be low!

Derek

In Aberporth, there is some fog on the coast with a temperature of 16 Celsius, while in Monmouth the temperature should reach a humid 27C 81F.

The first of the Olympic football matches have been played in very warm conditions in Cardiff, but there is a change on the way.

Over the next few days, it's going to turn cooler and fresher everywhere with a mixture of sunshine, cloud and showers.

On Sunday, the showers could be heavy in places with thunder. Daytime temperatures will range between 15 to 19 Celsius and with lower humidity it will be more comfortable at night for sleeping.

Next week looks more unsettled with some rain on the way with temperatures around the seasonal norm or a little below.

So, after the hottest spell of the summer so far in mid, south and east Wales, temperatures are set to drop.

However, the north and west, which have missed out on the hot weather, will enjoy a few sunny spells.

Derek

Temperatures this afternoon soared to 26 Celsius, 79 Fahrenheit in the shade, making it the hottest day at the show since July 2008 - and the hottest day of the summer so far!

The sun is very strong so people are advised to wear a hat, use a high factor sun cream and drink plenty of water.

Tomorrow and Thursday will be cloudier than today in Llanelwedd but it will remain dry, bright and warm with temperatures rising into the low 20s (Celsius). It will also feel humid with not much wind to speak of.

If you're in Cardiff tomorrow to watch the Olympic women's football at the Millennium Stadium it will be hot and should be sunny with a top temperature of 26 Celsius, 79 Fahrenheit.

On Friday, cooler weather will spread from the north-west with showers in places. The weekend will be cooler and fresher everywhere with a mixture of bright or sunny spells, showers and some dry weather too.

In London temperatures may soar to 31 Celsius, 88 Fahrenheit tomorrow - making it the hottest day of the year so far. The last time the Olympics were held in London in 1948 the games started with a heat wave but then it cooled down with a few heavy downpours.

This time round, it will be warm and humid for the opening ceremony on Friday evening but with a risk of heavy and possibly thundery showers.

After that it looks like turning cooler and fresher with sunny spells and showers.

So the weather may not be on top form for the first week of the Olympics, however the very wet conditions we had earlier in the summer are not expected to return. Overall, the weather will be typically British: changeable and mixed - much like it was in 1948!

In Wales, this July is already wetter than average but thankfully the jet stream has now moved further north allowing much drier and warmer conditions to take hold. I wouldn't be surprised if some farmers miss the show this year taking advantage of the dry spell, making silage and cutting hay. Mind you, it won't be dry and sunny everywhere this week. The north and west will be cloudier and cooler with some rain and drizzle at times.

Next weekend will turn cooler and fresher everywhere with sunshine and showers. The following week into August looks changeable with occasional rain and showers but with a few dry and sunny spells as well.

According to meteorologist Philip Eden, the first half of this summer has been the worst ever but at long last things are looking up for most of us over the next few days. The south and east of Britain will enjoy the best of the sunshine and the highest temperatures - up to 30 Celsius, 86 Fahrenheit in London! It won't be as hot as that in Powys but it will be warm and dry which is great news for everyone coming to the Royal Welsh Show.

Derek.

Torrential and thundery downpours are likely in places with a risk of flash flooding

Ladies night at Chepstow Racecourse has been cancelled because of the recent heavy rain. In the last six weeks, they say they have had 12 inches (1 foot) of rain with more rain in June than in February, March and April combined.

Tonight rain and heavy showers will spread south with the north turning drier after midnight.

Tomorrow will bring cloud and scattered showers with the showers heavy in places with a risk of thunder but some places will stay dry with bright or sunny intervals.

Highs 15 to 18 Celsius with a light to moderate west to north-westerly breeze.

Tomorrow night will be generally dry and cool with temperatures inland falling as low as 8 Celsius.

Sunday will be a better day overall with fewer showers with more places dry. It will be sunnier too although it may turn cloudy and damp later in the evening. Top temperatures 15 to 18 Celsius with a cool west to south-westerly breeze.

Sunday, 15 July is St. Swithin's Day but don't worry Sunday will be more dry than wet so hopefully it won't rain for the next 40 days...

There is more rain and drizzle on the way next week but later in the month there is a hint of better weather for the fourth week of July.

This is not definite yet but if it comes off it would be great news for the Royal Welsh Show and the start of the Olympics so keep everything crossed!

Mind you, it's not a completely dry story. The air is unstable with a few towering cumulus clouds and a scattering of heavy showers.

Looking towards ‪Pwllheli‬. Photo: Ben Wells

This evening any showers will die away to leave a dry, clear night and light winds. It will turn cool for the time of year with temperatures inland falling as low as 7 Celsius.

Tomorrow will start dry and bright with sunny spells but cloud and rain will spread from the south-west during the day. At the moment, it looks like most of rain will be in the south tomorrow afternoon. The north could well stay dry.

Friday will be unsettled with plenty of cloud, showers or longer spells of rain. Some heavy rain is possible too in parts of the north and north-east and I wouldn't rule out localised flooding given the ground is almost saturated.

Saturday will bring a few bright intervals but also showers, some of them heavy and thundery. Sunday should be a bit better; still a few showers but drier than Saturday and we should see at least some sunshine. Temperatures will be on the cool side at 14 to 17 Celsius, with a west to north-westerly breeze.

Looking ahead, there is still no sign of any prolonged dry weather on the horizon. The changeable/unsettled pattern looks set to continue for the rest of the July and into early August. The best I can offer is the odd fine day in between further spells of rain and showers.

Is our wet summer natural or is something else causing it? Could climate change be responsible?

Melting Arctic ice could be affecting the north Atlantic polar jet stream increasing the risk of blocking, leading to more extreme swings in the weather. Some prefer to blame a weaker sun for the changes in the jet stream like we are seeing now.

Whether you believe humans are changing the climate or not, it will be interesting to see what the winters and summers will be like in the years ahead and if the weather patterns we are experiencing now are a worrying trend or just a blip!

The weather was very mixed; we did enjoy some dry weather and sunshine but we had to abandon filming last Friday because of heavy rain, mist and poor visibility.

That's Welsh weather for you but it has been a very disappointing summer so far and July seems to be going the same way as June, in other words - wet.

A few places such as Rhyl, Mumbles Head, Hawarden, Aberdaron and St. Athan have already had more than a month's worth of rain. In Rhyl, (where the average amount of rainfall is 51.8mm) they've already had 68mm so far this month.

Meanwhile in Llandrindod in Powys, April, May and June were wetter than October, November and December 2011.

The jet stream is to blame for all the rain - it's still in the wrong position and should lie between Scotland and Iceland at this time of year but it is much further south than normal.

Across the pond, the USA is stuck in a ridge of high pressure with a record breaking heat-wave. There is another block of high pressure over Greenland and southeast Europe while the UK is under a trough of low pressure with no sign of it moving yet.

It would take some kind of jolt to get the jet stream to change its position and move further north. A hurricane in the Atlantic might do it but there's no sign of one in the near future.

This means the weather in our part of the world will continue rather cool and unsettled with more rain at times and heavy showers this week.

However, I can promise some dry weather and sunshine this week - one fine day and maybe even two in a row, if we're lucky.

Earlier today it felt very humid and some parts of the country were hit by torrential rain and thunderstorms causing flash flooding in some places.

There have also been reports of strange yellow dust covering cars and windows.

The dust is actually sand which has come all the way from the Sahara, blown our way by winds high in the atmosphere.

This does happen from time to time - a nuisance but completely harmless.

The humid, muggy air is now moving away and it will turn cooler over the next 24 hours with fresher Atlantic air. Low pressure will bring more rain and strong/ gusty winds too.

The weekend will be mixed and breezy with showers, heavy in places but Sunday should be better; more places dry with more sunshine and the wind easing.

The weather has been very topsy turvy so far this year...

After the warmest March in Wales for over 50 years, this was followed by one of the wettest Aprils on record.

Meanwhile April 2011 was the hottest since records began in 1910.

At Trawsgoed in Ceredigion over 177mm of rain (7 inches) has fallen making it the wettest June there since records began 58 years ago.

Philip Eden, who writes for the Sunday Telegraph, reckons that the first half of June across the UK was the wettest for 150 years.

While here in Wales, it's likely to be the wettest June since records began in 1910 beating the previous record of 183.1mm of rain in June 1998!

The jet stream (strong winds high in the atmosphere) is to blame for the inclement weather. It is further south than usual for this time of year and the weather pattern is stuck in a rut. Basically, Wales is in the wrong part of the roller coaster!

The jet stream (in blue) should normally be located much further north, between Iceland and Scotland.

You could call it bad luck but it does appear to be happening more and more often. The question is why?

The jet stream does vary naturally but is something else to blame?

This seems to be happening more often and it's well worth reading Paul Hudson's latest blog, my colleague at BBC Look North in Leeds, to find out possible reasons why. One reason could be warming in the Arctic.

The next couple of days will be humid and the air moist which means plenty of low cloud, mist, hill and coastal fog.

Further rain is likely at times too which may be heavy and thundery on Thursday.

Some dry weather is expected too and where the sun comes out it will feel very warm and muggy with temperatures rising into the low 20's Celsius.

Friday will turn cooler with fresher Atlantic air. It will also be windy with showers or longer spells of rain.

The weekend looks mixed and breezy with sunny spells and showers. Top temperatures only 15 to 18C, 59 to 64F.

I am sure many people will be glad to see the back of June and praying for more sunshine in July.

However, it looks like the changeable weather will continue into the first half of next month with just a few fine and warm days in between the rain.

Derek

The heaviest rain today has been in parts of mid Wales and the north and north-west with some rivers becoming swollen.

At the time of writing there are currently six flood alerts in force for Wales.

Wet weather in June may be disappointing but it's not that unusual. Since records began over 100 years ago, 38 June's in Wales have been wetter than normal.

The average June rainfall is 86.2mm and the wettest June was in 1998 when 183.1mm of rain fell.

I think we've seen the worst of the heavy rain for the time being but there is more heavy rain to come over the weekend.

Most of the rain is expected on Saturday evening; overnight into Sunday otherwise I can promise some dry and bright weather along with a few showers and some sunshine. It will be breezy with top temperatures 14 to 17 Celsius.

Next week, Monday will be largely dry and bright but there is more unsettled weather on the way.

It should, however, become a little warmer and humid. At the moment, the signs are that the changeable weather will continue well into July.

Derek

Yesterday was also the longest day of the year, the summer solstice, with the sun overhead the Tropic of Cancer at 23:09 GMT.

Astronomically this signifies the start of summer in the northern hemisphere but it won’t feel very summery over the next few days as the weather is about to change.

Pressure is falling and there's more heavy rain and showers on the way with strong winds and thunder possible too.

The Met Office has issued a couple of yellow warnings for heavy rain. Yellow means be aware.

On Friday the north, north west and Ceredigion are at risk from heavy, persistent rain which could lead to localised flooding and some rivers are likely become swollen again.

The wind will also be an issue on Friday (fresh to strong) with gusts reaching 45 - 50mph on exposed coasts and hills.

You can keep up to date with any flood alerts or warnings that are issued on the Environment Agency's website.

The inclement weather (with below average temperatures) looks set to continue over the weekend with further showers or longer spells of rain, heavy at times, but hopefully it will dry and brighten-up on Sunday afternoon with some sunshine.

It looks like the changeable/unsettled weather is set to continue into the start of July.

There is still no sign yet of any prolonged, settled weather on the horizon. Just the odd day or two of fine weather maybe three in a row if we’re really lucky.

Derek

Today was also the longest day of the year, the summer solstice, with the sun overhead the Tropic of Cancer at 23:09 GMT.

Astronomically this signifies the start of summer in the northern hemisphere but it won't feel very summery over the next few days as the weather is about to change.

Pressure is falling and there's more heavy rain and showers on the way with strong winds and thunder possible too.

The Met Office has issued a couple of yellow warnings for heavy rain. Yellow means be aware.

On Friday the north, north west and Ceredigion are at risk from heavy, persistent rain which could lead to localised flooding and some rivers are likely become swollen again.

The wind will also be an issue on Friday (fresh to strong) with gusts reaching 45- 50mph on exposed coasts and hills.

You can keep up to date with any flood alerts or warnings that are issued on the Environment Agency's website.

The inclement weather (with below average temperatures) looks set to continue over the weekend with further showers or longer spells of rain, heavy at times, but hopefully it will dry and brighten-up on Sunday afternoon with some sunshine.

It looks like the changeable/unsettled weather is set to continue into the start of July.

There is still no sign yet of any prolonged, settled weather on the horizon. Just the odd day or two of fine weather maybe three in a row if we're really lucky.

Derek

In Trawsgoed, Ceredigion over 171mm (6.7 inches) of rain has fallen so far this month which is more than double the June average of 78.5mm.

Thankfully, the next few days are looking more summery with a mixture of broken cloud and sunny spells. Wednesdayis likely to be the warmest day of the week with top temperatures 19 to 21 Celsius.

Coastal areas will enjoy the best for sunshine but it's not all plain sailing with a few scattered showers likely. One or two of these may be on the heavy side but they will be hit and miss with a lot of places staying dry.

Later in the week the weather looks like turning unsettled again with low pressure moving in from the Atlantic bringing yet more rain, heavy showers and strong winds.

The rest of the month looks changeable with the jet stream coming and going with low pressure alternating with high pressure.

Some days will be better than others but at the moment there is no sign of a repeat of the very warm and sunny weather we enjoyed in March and in late May.

Andrew Morgan sent this picture to me on Twitter showing rough sea and waves at Bracelet Bay on Gower.

Shelley Page took this one: waves crashing over the harbour wall in Porthcawl.

Elise Jenkins captured this fallen tree on the Taff Trail in Cardiff.

Fallen tree. Photo: Elise Jenkins

The strongest winds and gales have been in the south and west, especially on the coast. Mumbles Head in Swansea recorded a gust of 67mph. 50 to 75mm of rain (2 to 3 inches) has also fallen in places in the last day or so. So many rivers are swollen. At the time of writing, there is one flooding warning in force in Aberystwyth and 14 flood alerts.

And we're not out of the woods yet. There is still a Met Office warning in force for both heavy rain and strong winds until midnight on Friday. Stormy weather at this time of year is not welcome but it does happen from time to time. You may remember the Fastnet Storm of August 1979.

By 7am tomorrow morning the low pressure responsible for the inclement conditions will be over the North Sea so tomorrow the weather will gradually improve. Mid Wales and the north will start off cloudy with some rain but during the day, the rain will turn lighter and clear so the whole country will turn drier and brighter during the afternoon with some sunshine. The wind will continue to ease as well so feeling warmer than today. Top temperatures 14 to 17 Celsius.

I will be in Rhossili tomorrow to open the Gower Walking Festival. After the weather we've had today, tomorrow will be lovely in comparison!

Tomorrow night I wouldn't rule out a shower in the south and west otherwise it should be dry. Some mist forming and quite cool as well. At the moment, I'm not 100% sure about how Sunday will turn out. There is a risk of some rain, especially in Mid Wales and the south but it may miss us. So keep an eye on the forecast over the weekend.

Next week looks mixed. Sunny spells and showers. Heavy downpours likely in places with thunder. But there is a hint of better weather later in the month so don't put the deckchair away just yet and enjoy the sunshine tomorrow.

Met Office weather chart for Friday 8 June 2012

The south and west will bear the brunt of the gales, especially on the coast and on high ground with gusts around 60mph or more in exposed locations. The wind could bring even down a few trees given they are in full leaf. Poor travelling conditions are likely too with a lot of surface water and spray on the roads and motorways.

50 to 100mm of rain (two to four inches) are possible on high ground in the south and west and parts of Mid Wales by the end of tomorrow. Rivers will become swollen and there is also a risk of some flooding on the Bristol Channel coast due to the combination of high tides, between 9 and 10 metres, and strong onshore winds.

Over the weekend, the weather will improve. Turning drier and brighter with some sunshine and lighter winds. Perhaps a few showers on Sunday.

The changeable/unsettled weather looks set to continue for at least the next 10 days with a mixture of sunshine, showers and longer spells of rain at times. Heavy downpours are likely in places with a risk of thunder. There is no sign yet of any prolonged settled weather on the horizon but some days will be better than others.

In the meantime, take care if you are travelling in the next 24 or 36 hours, we are in for a dose of rough weather! If you take any good pictures please send them in either by email to dereksdiary@bbc.co.uk or on Twitter. You never know, they may end up on the telly!