Category Archives: Hailstorms

Storms that produce hailstones

Supercell with very large hailstones near Ebor 10th January 2018

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Supercell with very large hailstones near Ebor 10th January 2018

What can be said, in some respects a perfect chase tactically and with very large hailstones - something missing in the most recent chases. Critical errors had been made at critical times that led to unplanned outcomes. My philosophy is if I had not targeted a storm then I didn't deserve getting it. In this case, targets had been set but distractions had totally quashed any recollection of those targets. Well - that is until after the chase! Enough said... It is often said that too much data can add to the confusion!

Leaving Sydney early, I wasted little time in getting to the target of Ebor. I was fully aware that much depended on the positioning of boundaries as to storm initiation. First stop lunch at Thora at the foot hills of the Dorrigo Plateau and then Dorrigo.  The waiting game was short lived with the usual suspect cumulus developing near Ebor. 

Arrival to Target

I progressed towards this cumulus cautiously checking whether cumulus had developed further back. Instead, something was wrong - the cumulus had not consolidated near Ebor. More cumulus had developed further west that seemed higher based. Nerves kicked in. Was it the confusion, or was it the wait? Had I come up for nothing! Once again, I had to remind myself that CAPE values on the models were near or in excess of 2000 J/kg with good moisture and lower level turning. It was early and patience required.

Entertaining myself between Ebor and Guyra, the cumulus nearby dominated with any hope of development in the Dorrigo to Ebor corridor diminished. The boundary was set further west - the nerves settled.

A couple of showers developed but the one east of Armidale although weak had tapped low level moisture with a consistent lowered base. It was difficult to ascertain its direction - radar providing the key.

Developing Supercell Structure

An east-northeasterly course put the storm's intercept point at Ebor. My first move was merely a tactful one - after all, the storm was not intense. The lowered base continued to feed off the moisture. Inflow structure persisted as I made the Wollomombi turnoff. I felt emotions of frustration and excitement! The storm had remained organised and dumped hail as I approached the anvil canopy. Lightning increased and the storm literally exploded! But views were limited and I had to make do with what view options arose!

The storm to my surprise had made a northerly track - just in time too! This was turning into a beast with a consolidated rippled base and inflow tail in what seemed to be a wall cloud and shelf cloud combination. And that green tinge! Wow! It was like a fluorescent glow. Cloud base just above the ground with shelf or inflow feeding off the ground! Over a hill, I could simply not resist another perspective shot! The anvil streamed off to the east! It was pumping lightning at an increased rate but I was here for one thing - hail!

The Core Punch

Out to the main road presented an ominous sight! Tripod and camera out there capturing time-lapse and then the infamous error that had plagued this trip - the recording had stopped. No time for panic - IPhone 8 should be fine to capture video holding as still as I can this North Coast style spectacle. The shelf cloud and wall cloud region extended to it's northwest and seemed to wrap (Nick Moir texts me a little later to indicate what seemed to be a hook). 

very large hailstones

very large hailstones

Then I heard something nearby on the road. Looked around. Nothing. Then moments later another. It seemed like I was hearing hail but unable to see anything. Then it dawned upon me. I had dismissed the distant constant sound. Then another splatter. I captured over a minute of video and then could see hail was imminent. They were not small either 2 to 3cm hailstones.

Back in the car, hail increased in intensity. no chance of escape unfortunately. Pure hail now falling intensely. I carefully U-turned and headed west northwest - the cloud mass and base lining the road - the core about to unleash. Hail almost covered the road as the torrent of near pure hail fell profusely. Deeper into the core and thud! Even larger hailstones! Demister on it was still difficult to see. An immediate hail fog had set in for good measure! After about a kilometre or so, a side road opportunity presented an open area to move away from trees. Constant gold balls or larger hail pounded the vehicle. Tree leaves were being stripped constantly.

I positioned myself just in case larger hailstones feel as the main core passed over. The torrent continued for what seemed more than 5 minutes. I attempted to check some hailstone sizes but I was getting drenched with continuous rain. And of course occasional crackling thunder did not make it safe! I went further up the road and the sporadic very large hailstones were still falling. Soon, all that remain was the annoying rain. Difficult to measure without being soaked and cold.

Hail measurement time

Given the storm had moved into sparse road regions, I remained to document what I could. 4cm hailstones in my location was simply not right. Further up the road, I checked intermittently measuring hail 4 to 5 cm and then finally hail length of some of the wierdest fused hailstones I had ever come across at this size neared 6cm. Stripped leaves littered the road for about 10 kilometres!

After several measurements along the several kilometre path, I decided to head west where other storms had developed. Furthermore, it would allow me to see whether this storm was still severe. It seemed to have weakened back-building somewhat. However, on approach to Guyra, one major pulse invited me to the next phase.

The challenge was to intercept prior to Glen Innes Grafton route. On approach to Glen Innes, the storm on radar seemed to line out with a northwest back-building behaviour. Instead, I turned down towards Inverell for peak of other active storms. Within 30 kilometres, it was evident the storms were high based! You wouldn't believe it, an intense black cored storm on radar had side swiped Guyra. About turn and my determination was to get to Glen Innes Grafton road once again.

A magnificent shelf that blended into the undulating landscape  greeted me! So, although not intense, at least a secondary storm was observed. It was reasonably lightning active and I allowed the whale mouth to pass across to the northeast. This basically ended my chase day. An intense few hours with a few more anvil crawlers and bolts observed on the way to much awaited meal at the local club.

A very enjoyable day indeed.


Rotating Base and Hook Echo Grafton to Yamba supercell

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rotating base with hook echo on radar

Rotating Base and Hook Echo Grafton to Yamba supercell 1st January 2018

A spectacular day in north east NSW with a supercell producing a hook echo. With a target of Coffs Harbour to Grafton, everything timed to perfection. I ended up having lunch at Coffs Harbour and ventured north with a full tank of fuel. 

rotating base with hook echo on radar

rotating base with hook echo on radar

Conditions were meant to be ideal for supercells and low bases. Perhaps the upper levels were a little warmer than ideal but with sufficient heating and dew points, the cap would be over come and storm tops reach high up. Upper level shear was excellent thanks to an upper level sub-tropical jet!

The first cell developed almost in timing when I was near Nana Glen. An anvil greeted me and streamed off overhead. The side anvil although immensely crisp showed signs this storm was not mucking around. At Glenreagh, it became apparent that viewing would be difficult due to the lowered bases! I knew this region and immediately relocated in the region 10 to 15 kilometres north. Although just in sunshine, the base presented itself with a lowering. At first I scoffed it off but within the next 20 minutes it became organised showing rotating wall cloud structure! 

Wall cloud and Hook Echo on radar appears!

Fortunately, I had for the first time realised there was a road option and I followed it to the Pacific Highway. Disaster! My camera could not shoot with an error! A base was clearly turbulent and likely rotating overhead! IPhone time! But as if nothing had happened, with a little less panic and fiddling with the camera, it worked and I got the shots. 

No enroute to Grafton, radar indicated a direct course to Yamba. And it was possible to keep up! The hook behaviour could clearly be observed with with hail shafts in a circular fashion at the read of the storm. Finally at Meclean, I was in time to observe the low base and inflow streamers. Dew points along the coast including Yamba were 26C! Insane! The combination of this and sufficient heating allowed the storm to traverse the coastline. Added to the spectacle were the pulsating bolts - obviously a new updraft exploding overhead. The bolts were dropping in front of the structure!

rotating base with hook echo on radar

rotating base with hook echo on radar









See : 128km Radar Loop for Grafton, 13:00 31/12/2017 to 13:00 01/01/2018 UTC

Supercell Outbreak Darling Downs and NE NSW 26th December 2017

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Supercell Outbreak Darling Downs and NE NSW 26th December 2017

Models had been excited for about a week with the possibility of a supercell outbreak including some intense supercells across SE Qld and North West Slopes and Plains. The instability was in place together with a likely dryline further west. The convergence of boundaries and this dryline coupled with favourable shear profiles produced ideal conditions for supercells.

The cap held down throughout the afternoon and eventually the storms exploded first in NSW and then in SE Qld. Three isolated supercells developed across the Darling Downs allowing for sufficient space for energy. One particular supercell produced hailstones to 11cm in diameter!

Unfortunately, we made a wrong move and took bad road options although we slavaged a chase with a storm coming to and across the border of NSW to Queensland. This was to be the 3rd supercell in a line from the northern intense supercell. Although it seems a wall cloud was in view in specific phases, it was not sustained and then outflow dominated any attempt to organise. Updrafts can be clearly seen to rotate. Lightning was pretty intense in some of the phases particularly once the storms punched into the upper atmosphere.

Another storm intercepted briefly on the way amongst a break in the rain near Inglewood.