Dunsandel funnel and big hail

Location: Canterbury, New Zealand

  • Funnel
  • ,
  • Hail
  • ,
  • Lightning

It was a long time waiting but a good setup was finally on the way and alot of us Christchurch chasers were free! I put the word out to a few storm enthusiast friends to come over as they wanted to do a group chase, and then we headed out when things looked good. Most of the time as bad as it may sound I don’t like to do group chases as I don’t want to have to make decisions for others while in the field, if it’s just me I can deal with my own decisions whether they end up being fruitful or if nothing happens at all then I don’t have to worry whether others might be let down etc..

Convection started off quite early on this day, the main trigger (a convergence) we were expecting wasn’t due till the afternoon however the air was unstable once the surface temperature got up enough in the morning. Banks Peninsula acted as a trigger and a cumulonimbus cloud formed around 10am which then produced quite an amazing looking waterspout! My cousin Lanie Astley who lives up on the Port Hills managed to snap this shot of it, it went down into the water just off Scarborough. There are quite a few other great photos of this event and a search on the internet may reveal others. We gathered around midday then headed up to the top of Kennedys Bush Road to see what was going on over the plains.

We couldn’t deduce much at this stage and briefly thoughts of missing the main event of the day started to creep in, was the thunderstorm that happened in the morning it?? But we thought of course more is to come, we headed back to my place and had a look at the weather radar and saw some development south of the Rakaia River and so that’s where we headed. Once near the Synlait Milk factory in Dunsandel the clouds started looking really good, we turned off the main highway and followed a road around the back of the factory when a funnel came into view! All of us terribly excited by this jumped out of the car and started photographing it and videoing. I didn’t have the tape on my video camera at the right spot unfortunately and missed videoing most of it apart from a little bit as it dissipated towards the end. Stephen Burrows managed to get a photo of it though but it quickly became rain wrapped and we had to jump back in the car.

Here’s a “link” to a video Andrew Massie took of the funnel while out chasing with us.

After the funnel had looked to of died we decided to move further southwest, an interesting aspect of these initial storms was in a way at the surface they were moving from northeast to southwest which is a very unusual track for storms in Canterbury to take. Most of the time they will move southwest to northeast. From memory an eventual southwesterly change moved through pushing this system to the north later on in the day. We crossed the Rakaia river then headed south a bit more before going inland and set up waiting for further action, the skies did look quite thundery. Eventually a wall of hail looked to form and started moving towards us, even the sheep in the paddocks near by knew something was up as on mass they all started heading for the shelter of the hedges.

The hail got closer and closer then started falling pinging off the car everywhere, it seemed to go on for quite a while and was relentless. It also got quite big, some of the biggest hail I’ve been in while out chasing in Canterbury up to around 2cm in size.

The roads near the end of this event became quite white and when we drove off driving became difficult for a time.

We drove south after this to just north of Ashburton where we waited around for a bit at a rest area, other people looked to have the same idea to as the weather conditions made driving quite treacherous. Not much seemed to be happening so we started to make the journey home, on the drive north we could see a storm had developed just south of Christchurch and looked to be moving over the city. Steven Graham went out and managed to capture a few photos of lightning with his digital camera at the time which are superb!

Mike Stewart and Jason Tippet who were following us in their car for most of the chase arrived back to Christchurch and the streets were flooded near Mike’s place in Addington! Especially the intersection of Lincoln and Wrights Roads. A memorable chase for us all that day with a funnel sighted and big hail!!

Weather Maps

1800z 17/1/2009
0000z 18/1/2009
0600z 18/1/2009