Saharan dust has reached up through Europe this week. Calima is the Spanish phrase for this warm haze and there have been stunning satellite images and noticeable dust coverings.
Credit: European Union, Copernicus Sentinel-3 imagery
This week has seen western Europe sprinkled with Saharan dust as a warm flow brought suspended sandy particles up from NW Africa. In a moist, humid air stream it blanketed southern Spain and managed to reach southern England by midweek. The synoptic set up lead to some stunning satellite images from above and at the surface, the settling dust gave intriguing covering to many objects. There have been yellow, orange, red and purple skies. Thick dust and poor air quality. Rain, wind and high waves for Iberia and the western Mediterranean with the resulting combination producing #BloodRain, a reddish drizzle. Other hashtags of the week have been #PolvoSahariano (Saharan dust) and #Calima.
The low 'Celia' in the western Med. and the expansive frontal boundary from western Europe up to Scandinavia, with bright white cirrus, the dust and even a darker shadow showing along the distinct cloud edge.
Calima is a Spanish word for sand or dust suspended in the air. Like haze, it can be from natural particles or pollution. Air quality then suffers. These Saharan dust events do occur quite regularly but more so in summer. The Canary Islands are more prone, being off the coast of NW Africa and just catching the Trade Winds. The sky turns orange, pink or red and it can cause health problems as everything is surrounded by dust. If it rains it is known as mud rain or blood rain, and this can help coat surfaces with the distinctive mess.
The dust reached Germany and Switzerland as AEMET (Spanish Met Service) called the event ‘extraordinary’ due to its duration and extent. Also, the concentration of the dust in the air was very high. Visibility and air quality were poor which impacted travel in the south of Spain and to the Canary Islands. There were jokes about it looking like a Martian landscape with yellow skies and a blanket of orangey-red dust over southeast Spain to start the week.
By Wednesday, the skies across the UK were strange colour almost eerie at times as the dust arrived.
More Saharan dust still feeding towards the Canary Islands at the end of the week.
A huge buckle in the Jetstream had left a cut off low pressure near Iberia. A blocking high pressure over northern Europe stopping all incoming traffic from the Atlantic. A low, Storm Celia was named and as this rotated in place, it churned up plenty of unsettled weather which continued all week. Strong winds disturbed the desert dust and sand and it was thrown northwards from Algeria and Morocco across the Mediterranean picking up moisture. Celia kept the weather unsettled and active.
A frontal boundary extended up through mainland Europe, with a mass of high cloud and the suspended dust. This came up against a nose of high pressure coming over southern UK and incoming colder air from Iceland. So there were clear skies butting up against the ribbon of white cloud giving distinctive satellite images. Some showing the pinky orange of the dust.
For the UK, there were pretty colours in the skies and people in southern Britain and the Channel Islands saw a covering of sandy dust. Annoying for those who had washed their car or windows, intriguing for others. The dust is getting mixed up in the atmosphere over Europe, still swirling about but more diffuse now.
Spanish mountain snow with a pinkish tinge
Over the UK there will be fine, settled weather this weekend. Nearby high pressure (1050hPa) will keep our weather dry and on Saturday, western areas will feel warm, around 18 or 19C for sheltered NW Scotland. Looking fine and warmer more widely next week.
