Met Office predicts unusual 'coronal hole fast wind' potentially leading to northern lights on November 4 and 5
by Ben Hurst · Wales OnlineThe Met Office has said that an unusual astral event could see a serious display of the northern lights. Those watching the skies this evening and tomorrow (November 4 and 5) could be in for a treat as the nation’s forecaster has said there is the possibility Earth may connect with a coronal hole fast wind.
The Met Office said in its Space Weather Forecast: ”Through 04 Nov there is the possibility Earth may connect with a coronal hole fast wind, this may allow aurora to become visible at times across the far north of the UK and similar latitudes on the evening of the 05 November. Later into the period aurora is expected to return to background levels.”
Experts said that they were expecting moderate to High solar activity with Moderate flares expected, and a slight chance of Strong flares. The best time to spot the Northern Lights tends to be between 10pm and 2am. Aurora displays occur when charged particles collide with gases in the Earth’s atmosphere around the magnetic poles. In the northern hemisphere, most of this activity takes place within a band known as the aurora oval, covering latitudes between 60 and 75 degrees.
When activity is strong, this expands to cover a greater area – which explains why displays can be occasionally seen as far south as the UK. Northern lights are caused by a phenomenon called coronal mass ejections (CMEs) that erupt from an active sun spot. Combined with solar flares, they can create solar storms that interact with Earth’s magnetic field or magnetosphere.
In terms of the last 24 hours the Met Office space weather report says: “Solar Activity: Activity was moderate with four Moderate flares, the largest of which from a developing region in the southeast. There are thirteen active regions, including three as yet unnumbered regions.
“The spot mentioned above has become larger and more complex in recent hours and has been responsible for several moderate flares, with a region approaching centre disc also showing some complexity. Numerous spots are set to rotate off the western limb in coming days with several also rotating over the eastern limb which will have to be further analysed as they rotate further onto the disc. The other spots on the disc have remained fairly stable, or are showing signs of decline. “
It adds that in terms of solar activity it’s expected to be moderate or high, with flares potentially strong. A coronal mass ejection which happened on Oct 31, could give a ‘glancing blow’ to the Earth today (November 4) meaning northern lights.
NASA has confirmed the onset of a ‘solar maximum’, which is set to supercharge the night sky with stunning displays over the coming year. Occurring every 11 years, this phase is marked by an uptick in sunspots and solar flares. The Met Office has indicated that this could mean “an ongoing chance of further space weather activity, and ultimately the potential for aurora visibility here on Earth”.
The Northern Lights, also known as the aurora borealis, have already graced UK skies recently, courtesy of solar winds from solar flares or coronal mass ejections (CMEs) mingling with our atmosphere. With the solar maximum poised to amplify such events, the chances of witnessing the Northern Lights even in lower latitudes across the UK are looking up.
Krista Hammond, Space Weather Manager at the Met Office Space Weather Operations Centre, has given some insight into the current solar cycle. She said: “We’re now in the solar maximum phase, which means there’s more frequent sunspots and solar activity in general. While it’s not possible to know precisely what this means for individual Earth-directed solar events, it does mean there will likely be further chances of aurora visibility in the UK in the coming months.”
Ms Hammond also noted that the solar maximum phase could last a year, making it difficult to pinpoint exactly when the number of sunspots peaked until after the event. The Met Office highlighted in a blog post that a geomagnetic storm caused by solar flares and CMEs in May was the strongest in two decades.
After the solar maximum, solar activity will decrease, reaching the solar minimum, during which aurora sightings will become less frequent. However, they will not vanish completely. Ms Hammond clarified: “While the total number of sunspots will start to reduce after solar maximum, we will continue to see space weather throughout the solar cycle, even as overall activity declines. Indeed, in some solar cycles, the larger events can happen as the Sun transitions back towards solar minimum.”