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This is the first of two image reports from August 2nd 2008. I was still on a high from August 1st due to the solar eclipse, funnel reports, then the Maghera Mesocyclone later that evening. The action wasn't over yet though because another convective/thunderstorm outlook had been issued for N. Ireland on Saturday 2nd. Conditions were pretty much the same as the day before with a Wly air flow bringing showers across Ulster from the Atlantic. There was plenty of instability, vertical wind shear, strong solar heating and a decent enough lifting index so there was a general risk of thunderstorms, and at the very least, some photogenic convection. The risk of funnel cloud development was present so I was on the look out for those. My other goal was to try and catch a good gust front, the chances of this were good today, and because they would arrive from the W I should see them head-on so they should look very dramatic. I relocated to the countryside and set up my camera and tripod in an elevated field which gave me a good 360 degree view of the horizon. The convective scene were fantastic, in fact August 1st and 2nd produced some of the best convective structures I have seen during 2008 to date. The storm clouds were aligned in countless parallel streets running W-E. One line in particular to my S not far from Slieve Gallion was spectacular sporting phenomenal cumulus towers and Cbs with giant wispy anvils. Each one of them looked capable of dropping a funnel. These cloud tops were intense white in the Sun and had well defined dark bases with showers and lowerings falling down. There was so much going on that it took all my concentration to study each and every one of them because they all needed to be monitored. It was so sunny and hot followed by periods of overcast and showers then hot again. During the afternoon I witnessed three very good gust fronts. The second of these was one of my favourites all year. It did not have a shelf as such, just the classic cloud roll however the curvature of this was really something. The following images show this gust front. These are all very low resolution images.
A mess of dark cloud gathered in the W over the Sperrin Mountains and began to very slowly organize and move my way. This is zoomed in. Heavy precip is already falling from the SE side of the system. That's Slieve Gallion in the distance to the L. Another cell above me is dropping rain onto the camera lens.
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You can see the classic curve of the gust front forming already with a long precip curtain becoming more active. Moving R to L and towards me. The storms were very slow moving today so I had plenty of time to watch them form and get images. This might not look big on the image but believe me it was and it was still some distance away. Note the towering cumulus clouds catching the Sun above. There was dynamic scud movement on the leading edge. I was getting a little more observant now incase a c-g bolt dropped out from the rain curtain. There's a high chance of this happening with any gust front. One of my goals is to get video, or better, a still image of a c-g bolt in the rain curtain from a gust front. I will be trying my best to do this in the future.
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Fully formed gust front now in action with very bright and dense precip curtain. That detached lump of cloud in the middle of the bright curtain looks weird. It's being pushed along by the outflow air. The S side of the GF had already developed into a wonderful curve which looked very low to the ground. Maghera is getting very wet now. Actually from looking at that image I would say that the GF would be directly over my house at this moment. I like the very well defined precip curtains falling down in strands ahead of the curve. These look great on the high res images.
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GF much closer now showing its true size. You can see better detail in the precip curtain now. I would say that the radar signature would be showing a red return at this moment in time. This image covers the S to SW compass points. The GF continues out of the frame to the R.
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I love gust fronts, there's a great feeling of excitement watching as they creep towards you from the distance constantly changing shape and getting larger and more menacing as they do so with the ever increasing risk of getting lightning. I was amazed there were none coming from this system, I kept taking video footage just incase because if I was lucky enough to catch one I could extract the still frame later. Visually at the time, this was a wonderful sight, the dark gust front with bright rain core contrasting against the green fields was a joy to watch. It's at times like these that I think mother nature is incredible.
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I deliberately go out to the country for several reasons. Apart from the obvious photogenic aspect of the country there's the most important factor of all...peace and quiet. I want to get away from other people so I can enjoy these storm structures without being disturbed. I thought I would be fine out here. There's a narrow country road to my L out of the frame. I have two walk through two fields and climb over a gate to get to it. The road continues W until it connects with the main Coleraine Road. You can see it on the LHS and extending towards the middle of the frame in the direction of the gust front. I only seen two vehicles here the entire time. One was a family car which drove by. I was standing in tall grass which came up to my waist when these images were taken, the grass would have hid part of me and my tripod from passers by, not to mention the hedgerows. However there's always a nosy prat somewhere who has to stick his nose in where it's not wanted. This second vehicle, a silver range rover, drove along the road and managed to spot me. I knew because he slowed down but I thought he would loose interest and drive on. He stopped and stared at me, then reversed the range rover to a better spot on the road and watched me. The engine was off. I was getting really pisst off at him. From his vantage point all he would have seen was the top half of my body above the long grass. My tripod and camera were hidden from view. I suppose from his point of view I would have looked suspicious. He kept staring which was making me feel very uncomfortable, I was going to shout down at him 'what are you looking at!' but decided not to fuel the situation. I then thought that maybe he was a local farmer and that he even owned this field. I was trespassing. I was already mentally preparing my story incase he walked up the field after me. By his body language I reckoned he was surprised I didn't run which made him a bit more unsure of himself. I thought I would subtly show him what I was doing so I lifted the camera up to my face, looked through the view finder and pretended to take some images of the sky. I made quite a show of this and he seemed satisfied and drove off still looking out the passenger window.
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Going wide with the lens now. You can see the distant convection to the L.
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Getting darker and cooler now as the gust front and outflow get ever closer to me.
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The leading edge of the gust front passed directly over me and developed into an incredible curve extending from behind me, through the zenith, and into the S low to the ground. This was awesome looking!!
What a treat to see this. I get out my mobile and text John McConnell to tell him that one of the best gust fronts I had ever seen had passed over me. Then the outflow arrived. The temp dropped like a stone, it got very dark and the first drops of rain hit my face. Then it was as if someone turned a tap on and a complete deluge of torrential rail began to fall at high speed. There was a small derelict building nearby and in the 10 sec's it took to get inside I was completely soaked to the skin. This was definitely red on the radar. The downpour was phenomenal, due to the slow motion of the storm system it didn't stop for about 20 min's. Luckily this open countryside is on high ground, had it have been over a town or low ground it would have caused flash flooding. I was shocked that no lightning came from it. I was better of inside anyway just incase there was an isolated bolt. I would have been in a good location to get hit by one if there had been.
This a 2x speed timelapse video I made of the gust front. Even at this speed you can see how slow the system moves from R to L. At the end I have showed some footage of the heavy outflow rain and wind taken from inside the building through a large hole in the brick wall. The rain was even falling through cracks and holes in the corrugated tin roof and falling in heavy drips down my neck. Thank goodness I had somewhere to shelter. The rain core eventually drifted further E and the heavy clattering on the tin roof stopped. The Sun was illuminating the country again and it felt very hot. I went back into the field and looked at the rear of the structure. It had developed a wispy white anvil with large but subtle mammatus bags. I stayed out a few more hours and this same process repeated itself in regular bursts only from lesser quality outflow structures. I decided to head home but as I was walking through the fields more organized structures moved in.
This began as a long row of black cu towers running in a straight line from W to E. All the towers got organized very quickly and merged together into one system. The black base of this linear structure with high vertical extent had numerous areas of rapid rotation. All these lumps of scud over a wide area were rotating and looked capable of dropping something.
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I was now located between two fields along a tractor path which had a high bump in the middle and lower level muddy tracks on either side. It took a bit of messing to get the tripod set up and leveled. Look at the effects of wind shear on this system. The inflow (foreground) and outflow (distance) are very well separated. Look at the highly structured base and wide precip curtain falling from the other side. This is highly organized. The last time I seen a base like that was in early May which produced a brief thunderstorm with the largest hail stones I have ever seen from here. There was a thunderstorm in Ballymena and some scattered sferics but why was this not producing any?. It certainly looked the part. You can see just how intense the rain is, and that the rain drops themselves are of large size. This is a shutter speed of about 400/sec (still a bit bright) but if you look at the dark clouds from the centre of the image to the L you can see numerous large rain drops caught in the image. They are trailed out as they fell similar to star trail images taken by a long exposure at night. The structure is moving away from me here. I headed home after this soaked to the skin and quite hungary but I had a fabulous time. I was happy just to see that gust front despite everything else. However the day was not over yet and the universe had a surprise waiting for me which would form a few hours later. This will feature in my next image report.
Martin McKenna