BALL LIGHTNING AND OTHER MATTERS

[Stanley]

BALL LIGHTNING AND OTHER MATTERS

26 February 2005

As I get older and more experienced I realise that some of the things I have seen and experienced were quite rare. I was reminded of this last night when I watched a film about extreme weather and when I saw their depiction of ball lightning I thought to myself ‘Good to tell these blokes have never seen ball lightning.’ Their version was pathetic and nothing like the real thing. I have the advantage of having seen a classic episode. I wrote this down five years ago in the memoirs I did for my grandchildren but have decided it could benefit from expanding a bit. I can’t remember the exact date, I think it was about 1969. I think it was at the same time that there were discussions about damming the Ribble at Long Preston to form a reservoir. This would have meant re-aligning the railway and the road and in the end it never happened. This might give a clue as to the date if anyone wants to research it further. Here’s what I originally wrote about it:

‘I had a funny experience one afternoon as I came down from Scotland with a load of beasts. I was just coming along the road into Long Preston and it was thundering but not raining. I saw something in the field to the right of the road in the river bottom which was so extraordinary that I pulled up at the side of the road and got out to watch. Another wagon stopped behind me, he had seen the same thing. What we were looking at was bolts of lightning striking the ground and where they hit they left a big blue ball of fire which rolled round for a second or two and then vanished with a sharp crack. There were dozens of these and I was fascinated, I had read about them but never seen them before. They were working their way over towards the road so I decided discretion was the better part of valour and drove on.

Years later I described this to a bloke who knows about these things and he told me that what I had seen was ball lightning which is a mysterious and very rare phenomenon. He told me he would have given his bottom dollar to have witnessed the sight, he had been studying it for years and never seen it! I had a similar experience years before when driving the tanker. I was passing Ferrybridge Power Station when I saw one of the cooling towers rotate gently and subside into the ground! I stopped and watched and saw another one do it. Years later I became friendly with the man who is production manager at Ferrybridge and he told me that it was a vortex effect that had done it and even though the towers were rebuilt in different positions and made stronger they still have a ban on traffic on the road between the towers when the wind rises above a certain speed.’

I looked on the web and found this:

‘A leading theory suggests that ball lightning forms when a lightning strike vaporises silica in soil. The silicon vapour condenses into a fine dust that is bound together by electrical charges into a floating ball, which would oxidise and glow’ (New Scientist magazine, 8 April 2000).

Here’s an expanded description of what happened that day.

It was a fine afternoon, as I remember it we hadn’t had any rain for a while but plenty of sun and the ground was quite dry. It was still good light but the sky was starting to cloud over. There was almost no wind and whatever the event was it was moving very slowly in an Easterly direction.

I’d heard a couple of thunderclaps as I came south through Settle and by the time I had got within a quarter of a mile of Long Preston the claps were more frequent and I saw a lightning strike in the valley bottom to my right. There seemed to be a glow on the ground after the strike and this excited my curiosity, I have always been fascinated by thunder and lightning so I pulled into the side and had a closer look.

I soon realised that this was unlike any sort of lightning I had seen before because all the lightning I saw was ground strike, no sheet lightning. The strikes were frequent, probably averaging one every thirty seconds. Each time there was a strike it seemed almost instantaneous and a single discharge. I can’t remember any forking or prolonged discharge. What was really strange was the aftermath of the strike and as I remember it this was the same for every strike, only the size of the remaining phenomenon was different.

As each strike occurred it created what I can only describe as a circular ball of what looked like plasma, not flickering at all but a steady contained ball of energy. The colour was bright but not dead white, there seemed to be a blue tinge to it. Once created these balls remained active for a period, I can’t say how long but some idea can be gained from how they behaved.

I’ve given a lot of thought to how big the fireballs were. I was viewing them as far away as the opposite side of the valley down to about 100 yards from the road and they seemed to be six to eight feet in diameter. I can remember one was behind an obstruction, a field wall I think and I could see the top of it above the wall. Now whether what I was seeing was a nucleus or the glow surrounding one I don’t know but they were perfectly circular and rolled on the floor. Once the balls formed they almost all rolled around in the fields. Some stayed almost stationary but most rolled quite a distance. The ground is fairly flat in those fields so whether the slope governed the movement is beyond me. Some rolled quite a distance, I can’t say how far but I’m fairly sure one or two did perhaps 100 yards.

When the balls vanished there was a loud crack, a very sharp sound, in military terms more like large calibre rifle cartridge rather than a 77mm anti-tank gun. In fact, thinking about it, more like a small charge of fulminate or very high speed gelignite than cordite or similar slow-burning explosive. Some ‘exploded’ in the open, some when they encountered an obstacle. I have a definite impression that they imploded rather than exploded. I didn’t see any of them cause damage beyond what looked like a faint puff of dust.

The area of impact was moving slowly towards me and when one struck less than 100 yards away I decided that this was looking decidedly unhealthy so I got going again and left the event behind me. I would say that I saw between thirty and fifty strikes, some of them close together but I wasn’t counting.

That’s about all I can say about it. I’ve done my best to report accurately but I know only too well how fallible memory can be.

WIND DAMAGE.
The Ferrybridge incident has been very well reported elsewhere I am sure. In later years I have become very friendly with Geoff Shackleton who was production manager at the power station and he has told me quite a bit about the consequences and what was believed to be the cause so my memory will be polluted by this knowledge. All I can say is that it was surreal watching those enormous structures slowly rotate and collapse. I think I saw three come down, one when I was on the move and two while parked on the hard shoulder trying to make up my mind whether I was hallucinating. Certainly an image that remains in the memory.

TORNADO
I’ve not actually seen a tornado come to ground but I did have a good view of a super cell in full flow which resulted in a destructive event at Dundas about three miles away from where I was in Northfield MN.

I think the year was 2002. I was house-sitting for some friends and it would be August I think. I took a close interest in the weather because it was so different than what we experience here in the UK. There was a channel on the TV which during the day showed the image from the Doppler radar which covered the area. The house had a large front porch protected by fine fly screens and it was from there that I watched the situation develop.

The possibility of a tornado warning had been forecasted for 36 hours so I was watching developments. The House I was in was a 150 year old wooden frame building, it was big and well built and as it had survived so long I didn’t have any qualms about being in it. Like all houses in tornado districts it had a deep cellar. This was handy for storage and the utilities but it’s primary purpose was as a tornado shelter. The drill was that if there was imminent danger a siren sounded just like the all clear sirens we had for air raids during the war. Everyone knew what it sounded like because it sounded at a certain time most Saturdays as a test.

I’ve always found that the biggest and best thunder storms are to be found in the middle of large land masses. Berlin had some good ones. What they call Tornado Alley starts in the deep South and runs up the centre of the States in an eastward curve that finishes up near the Great Lakes. Northfield in Minnesota was on the track but the storms were usually diminished by the time they reached there. As I understand it they are caused by a cold air boundary in the North acting as a barrier to northward moving hot air. I think the speed and position of the jet stream winds has a bearing on them as well. These blow at high altitude in an easterly or north easterly direction across the northern mid-west states.

On this particular day all the elements were in place and the Doppler radar was tracking a large thunderhead moving towards us at about 15 mph from the south west. When I say large; they estimated it was 85 miles across and over ten miles high! This was a significant cloud.

Shortly before noon it started to go dark as the cloud moved in and by 2pm the street lights had come on and a nasty wind had got up. The winds there are funny, not like our Atlantic winds, they seem to be more jagged and have hard lumps in them. I know that sounds funny but I’ve seen a gust hit a tree and take out all the branches on one side while leaving the other side untouched. They are vicious nasty winds, not a steady gale but powerful squalls. There was a bit of rain but not much and these nasty winds. Funny thing was the thunderhead seemed to be moving against the ground wind.

The tornado siren sounded about half an hour later. Now I had been told that when that happened you didn’t bugger about, you just got in the cellar, closed the doors and waited for the all clear. However, being 1.) a lover of storms. 2) a veteran of air raids in the war. And 3) a nosey bugger; I brewed up, got my pipe and went onto the porch to watch the show.

And what a show it was! The thunderstorm lasted for about three hours with almost continuous lighting and thunder. Many were inside the cloud and didn’t earth to ground but they were enormous. I watched my pot of tea jump of the table a couple of times simply from the concussion. The house seemed to move and all the time the wind was building.

I went outside and looked at the base of the cloud. It was very dark grey but the internal lightning flashes lit it and you could see it was boiling. It also seemed to be rotating from right to left and you could see a circular element on the base. Then it started to rain heavily. I found out later that a rain gauge only two blocks away measured over six inches of rain in 45 minutes and most of that fell in one spell of about 15 minutes. I’ve never seen rain like it, it was a wall of white and visibility was about 50 yards. The gutters couldn’t cope, the water was running straight off the roof like a waterfall.

By now the wind was better than a full gale, I have no idea what the speed was but the noise was tremendous. I have never heard or seen anything so dramatic apart from a very bad easterly gale I once watched sending waves over the cliffs at Dunnet Head once. It was a fascinating three hours and in the end gradually diminished to what we would regard as a very bad thunderstorm that carried on until the early hours of the morning. The drains and roads had coped with all the water and apart from a couple of trees that had been struck and some fallen branches there was no visible damage. The old house had weathered the storm.

The following morning I rang Grace, a long time Northfield resident that I knew and confessed my stupid behaviour. She told me to join the club, she said she and her husband Cliff had done exactly what I did, sat on the porch with a drink and watched the show. She said they had lived in Northfield for thirty years and it was the biggest storm they had ever seen. It was Grace who told me about the neighbour with the rain gauge.

Roger and Martha returned shortly afterwards, they owned the house I had been looking after. We went out to Dundas to look at the damage that the tornado had cause when it touched down there. There were no injuries but houses and farm buildings were scattered all over the fields. A combine had been lifted out of the building where it was parked and thrown a hundred yards across the fields and totally destroyed. There was no doubt that we had had a very narrow escape.

So that’s my tornado story. We often think we have severe weather here but believe me we have nothing like this here. I have seen whole rows of giant pylons cut down like wheat, advertising signs twisted and bent as if they were made out of wire and large buildings completely roofless. What struck me was that the buildings and drains were built to cope with the event. There was hardly any damage. I suppose that’s the key to survival in any disaster.

Looking back I suppose what I did was stupid and dangerous but I wouldn’t have missed it for anything. It was a wonderful sight and made you feel very small when you looked up at the base of that cloud at about 5,000 feet and realised how much energy was boiling away in there. We are really very insignificant and it makes you wonder how we have survived this far. Who knows, climate change might eventually do for us……

SCG/26 February 2005

I wrote that two years ago.  Geoff told me that the cause of the Ferrybridge Towers falling was vortices formed by the wind blowing at just the wrong angle on the two rows of towers.  I saw two come down and they seemed to rotate and crumple as they fell.  The vortices must have set up big pressure differentials and that's the same as a partial vacuum, they were sucked in rather than blown over.  Powerful stuff wind! Another thing that strikes me is that Swabs was built in 1876 and that looked like a Preston chimney, more batter and eight sided.