Scotland has been hit by 1800 lightning strikes - causing major travel delays across the country.

A yellow warning for thunderstorms has been issued for Thursday and Friday for areas including Dundee, Perth and Edinburgh. Six flood alerts have also been issued by environment watchdog Sepa.

Lightning strikes have caused damage to signalling systems across the country on lines such as Inverness to Beauly.

Passengers travelling on Caledonian Sleeper services also faced disruption after strikes damaged signalling equipment in the north of England.

More than 1800 lightning strikes occurred between midnight and 10am on Wednesday in eastern Edinburgh, central Fife and around Perth.

A ScotRail spokesman said: "Due to lightning damaging the signalling system between Inverness and Beauly lines are blocked meaning services are unable to operate at the moment.

"Staff have been mobilised and will arrive on site soon. Once we have more information from the ground we will keep you updated."

STV Weather presenter Sean Batty said temperatures could reach as high at 28C, causing further storms.

He said: "A large plume of very warm air is pushing north out of the Sahara and bringing record-breaking temperatures to parts of western and central Europe, as well as the UK.

"This air has become very humid too, which allowed thunderstorms to develop over northern France on Tuesday afternoon, where temperatures touched 40C.

"These thunderstorms drifted north and increased in activity as they crossed England and Wales on Tuesday evening, reaching southern Scotland by midnight.

"These storms then continued to drift north across the Borders, Dumfries and Galloway, Lanarkshire, Edinburgh, Lothians, Fife, then reaching Moray, Inverness, the north Highlands and Orkney by morning.

"Since midnight up until 10am on Wednesday, there had been just over 1800 lightning strikes in Scotland. The main concentration of strikes looks to have been over eastern Edinburgh, central Fife and around Perth, where there were 200 alone.

"The storms are now clearing away to the north of Scotland, with the storms moving north of Shetland after lunchtime.

"Scotland then returns to warm and sunny weather for most areas on Wednesday with temperatures around 25C Easter Ross, Aberdeenshire, Angus, Fife and the Lothians. The peak is likely to be around Moray or north Aberdeenshire where it could reach 28C."

Prestwick was the warmest area in Scotland overnight where temperatures reached 18.5C.

Lossiemouth in Moray had one of its warmest July nights since 1965, recording 17.4C during the night.

Sean added: "Thursday could be even warmer, and it now looks likely that the all-time UK record will be broken by exceeding 38.5C somewhere around London. In the central belt we may hit 30C, and close to 30C in Moray and in parts of Wester Ross.

"Intense thunderstorms look like developing following on from this hot day, with the focus on the east of the country where torrential downpours, hail and frequent lightning could occur on Wednesday night - one to watch.

"Scotland has experienced some very warm nights recently, with Aviemore and Drumnadrochit having their warmest July night on record on Monday night.

"Tuesday night was another very warm one with Lossiemouth having one of its warmest July nights since 1965 with the temperature staying at 17.4C.

"The warmest spots overnight were around west central Scotland and the south west of the country.

"Prestwick didn't drop below 18.5C making it equal to the previous two records set in 2011 and 2001. Renfrewshire had its warmest July night on record too with the temperature at Bishopton only dropping to 18.1C on Tuesday night.

"Glasgow's previous overnight July record was 19C, set in 1976, although difficult to verify now that the station has been closed down, but given how high the temperature stayed in Renfrewshire, I'd say it's likely that Glasgow had one of its warmest July nights on record too, if not its warmest."

Student Kevin Klein, 34, cycled to Calton Hill, Edinburgh at 3.30am to capture stunning pictures of the lightning strikes on morning as the sky was lit up.

The Met Office issued weather warnings for thunderstorms across Edinburgh today, with temperatures expected to hit 25°C.

Kevin, from Edinburgh, spent almost two hours photographing the spectacular display - despite being scared of the horrific weather conditions.

Kevin, a research and computer science student, said: "I checked the Met Office yesterday and it said there was a storm coming.

"I decided to cycle over to Calton Hill and I noticed the sky lighting up and got a few photos. The pictures I took you can see the lightning strikes. It was just a lucky shot.

"I got excited. The whole sky literally lit up for a second. I was scared to be taking pictures in those weather conditions but I love things like that.

"I like hunting sunrises, sunsets, lightning. I couldn't believe it to be honest. I ended up heading home at about 5am this morning.

"The first thing I did was go in for a shower because I was completely soaked."