I make no excuses for the fact I love severe weather. It’s been in my blood since I was young and the excitement of experiencing mother-nature behaving badly, has never left me. However this winter, in the UK, I got to experience a relatively rare but potent meteorological phenomenon. Not once, but twice within the one winter!
On the 8th of December, I headed for the Scottish coastline to capture video and take windspeed readings during, what was forecast to be, a fairly typical Atlantic wind storm for Scotland. However what I encountered was wind speeds higher than I had anticipated, with gusts reaching 78.4 MPH. (There’s a video I shot of the day’s events here)
Graph of the wind speeds I recorded in the 8th of December storm:
But this was no typical Atlantic storm, of which I’ve experienced many. This potent low pressure system formed what is known as a Sting Jet, a phenomenon which is a relatively recent meteorological discovery, after being first identified in the late 80’s.
The deservingly foreboding name is derived from the appearance of a scorpions tail, a good analogy for a hooked-shaped area of cloud at the southern edge of the low pressure’s centre. It’s at the very tip of this pointed cloud formation, where the edge of the cloud is evaporating, that the characteristically potent winds are found.
Since the Sting Jet was first identified, only a handful of atlantic storms have reproduced the phenomenon. In order to form, a Sting Jet requires the energy produced in a rapidly deepening low pressure system (one that is undergoing ‘rapid cyclogenesis’). However the UK is battered by many low pressure systems that have rapidly intensified, yet have not gone on to produce the elusive Sting Jet. The exact reasons why some low pressure systems produce the phenomenon and some don’t, is still the subject of discussion.
The formation of a sting jet has the potential to enhance the surface wind speeds by a further 25-30MPH, over those forecast for a typical Atlantic wind storm. Little did I know at the time of the 8th of December storm, that this was just a precursor to a future storm, which would bring disruption and structural damage to Scotland and Northern England on a scale not seen for decades.
On the lead up to the 3rd of January, the UK’s government meteorological agency, known simply as the Met Office, was already issuing weather advisories for an incoming low pressure Atlantic storm. The weather models were indicating the low pressure system would take a ride on a strong jet stream, and undergo rapid cyclogenesis, so the country was already preparing for a windy time. However this storm was looking to be nothing overly exceptional, especially for Scotland where we’re quite used to blowy weather!
As dawn broke on the 3rd of January, wind speeds increased rapidly over a very short space of time, accompanied by a rapid drop in humidity the textbook indicator of an approaching Sting Jet. Satellite imagery later confirmed this was indeed a sting jet event.
Here’s a graphic representation of data obtained from my home weather station as the sting jet approached, clearing showing the approaching sting jet by the rapid humidity drop accompanied by the sudden rise in wind speed (just after 5am):
The position of the sting jet itself, aligned perfectly with the heavily populated central belt of Scotland. There was structural damage experienced in almost every town and village within the central belt. After the storm had passed, it was hard to go anywhere without seeing the impact of the storm. Roofing tiles were blown onto nearby cars, trees were uprooted or snapped off and in some cases, entire sections of masonry and roofing material, were ripped from buildings. A number of trucks were even blown onto their side as they travelled on the busy motorways across the central belt.
Although the gust speeds in the 3rd of January storm were not as high as those recorded back in early December, the sustained wind speeds were much higher in comparison, attributing to the widespread damage.
Incredibly and thankfully, there was no loss of life in either wind storm. Given the extent of the structural damage, it was somewhat surprising there were not more debris-related injuries.
This winter has certainly reaffirmed my belief that weather still holds the element of surprise, even in this age of satellite imagery, radar and forecast modelling. Given the plethora of records that have been broken by this somewhat bizarre winter, I’m wondering what summer might now have in store for us living across the pond!