Reports have been flooding in on social media this morning on a rather unusual and eerie yellow or orange sky and reddish hue to the sun across the Channel Islands, southwest England, Wales, Midlands and northern England. Also people have been reporting an acrid burning smell.
The phenomenon is due to Storm Ophelia, currently arriving off the SW tip of Ireland and battering the south coast with 80-90mph winds, dragging a plume of tropical air containing dust from the Sahara Desert all the way from North Africa. Ophelia was a category 3 hurricane for a time over the weekend to the east of the Azores. The hurricane tracked northeast from south of the Azores over the last few days, before becoming extratropical last night as it was picked up by the jet stream and polar front, losing its ‘eye’ and turning it into an intense mid-latitude depression.
Its track towards Ireland from so far south in the North Atlantic has drawn a strong and deep southerly flow originating over North Africa, picking up dust from the Sahara but also bringing smoke particles from wildfires that have been raging across the Iberian Peninsula recently. Explaining the burning smell. The strange hue to the sky and sun has been caused by the higher concentration of dust particles refracting and reflecting the light from the sun, making it appear red. The highest concentration of dust appears to be carried in a narrow corridor just ahead of a cold front moving east across the UK, where southerly winds are enhanced. So eastern parts of the UK will probably see the sky and sun turn shades of yellow and orange too this afternoon, as the corridor of dusty air moves east ahead of the cold front.
A cold front, associated with cooler and fresher air from the Atlantic being pulled under Storm Ophelia as it tracks northeast, will sweep eastwards this afternoon, which will result in a cleaner and clearer southwesterly flow off the Atlantic removing the dusty air and removing high humidity levels, making it feel cooler and fresher tonight. Temperatures were as high as 20C across Cornwall before dawn this morning and temperatures have climbed to 23C across SE England this lunchtime.