The atmosphere over Britain is set to be touched by a saharan dust cloud later this week, carrying fine sand and minerals from North Africa and promising dramatic sunrises and sunsets. Satellite imagery on Tuesday (ET) showed a brown haze over Spain as the plume began its northward journey on warm southerly air. Forecasters warn the same dust, when mixed with rain, can leave dirty deposits on cars and windows known colloquially as ‘blood rain’.
Saharan Dust Cloud: What to expect
The plume is composed of fine sand and mineral particles lifted from desert regions of North Africa and transported thousands of miles on warm southerly currents. As these tiny particles remain suspended several kilometres high in the atmosphere, they scatter sunlight — filtering out the shorter blue and violet wavelengths and allowing the longer red and orange tones to dominate. The result will be striking displays of deep gold, amber and burnt orange at sunrise and sunset, with the brightest colours expected on Thursday and continuing into Friday (ET), especially when skies are clear at those times.
Immediate reactions
Forecasters at the Met Office warned of practical impacts as well as spectacle. Met Office: “The combination of warm air and Saharan dust may lead to some dusty deposits on cars or outdoor surfaces as the frontal rain washes the dust out of the atmosphere overnight into Friday. ” Honor Criswick, Met Office meteorologist, added that the band of cloud and rain could be heavy at times and that many areas will still see long sunny periods before any frontal rain arrives.
Quick context
The dust plume has been drawn north after Storm Regina tracked eastward into the western Mediterranean and pulled warm southerly winds up from Iberia, lifting dust high into the atmosphere. Movement of Saharan dust to the UK is a natural, fairly frequent phenomenon that usually happens a few times each year, most often in late winter and spring when southerly flows carry warm air north.
What’s next
Expect the most vivid skies across southern and central parts of England and Wales on Thursday and into Friday (ET), with clearer and cooler conditions arriving from the west by the end of the week (ET). Watch for dusty coatings on parked cars and windows after any rain front pushes through overnight into Friday (ET); the saharan dust cloud will likely linger in the high atmosphere for days before gradually drifting and settling. Officials will monitor skies and any washout effects as the plume moves across the country.
