Dust from Sahara leaves its mark

DEEP red sunsets and a downpour of red rain on Tuesday have been attributed to dust from the Sahara.

Meteorologist Vincent O’Shea said the very red sunsets of late are due to dust high in the atmosphere.

But it was the rain on Tuesday that brought it out of the atmosphere and down to earth, landing on every surface, and leaving people with a big clean-up.

West Cork-based Vincent  described how a cut-off jet stream, which originated over the western Sahara desert, has been streaming up over Ireland in recent days. This is, he said, in part responsible for the unusually fine warm weather we are enjoying.  

He described how the reddish sand particles get whipped up from the desert and are carried aloft where the southerly winds are particularly strong above about 10km. 

In such situations, Mr O’Shea said, the southern part of Ireland is most vulnerable to fallout of the sand or dust particles.

Although the phenomena was reported widely, West Cork got the heaviest deposits as some showery rain also affected the area on Tuesday morning. While not unprecedented, he said, it is quite rare to have all the necessary conditions operating in concert, especially rainfall. It is generally regarded as harmless.

A notable past occurrence was in November 1979.

This mostly affected the West Cork and Waterford regions.

The weather system has also been the cause of the recent stormy and wet weather over Spain and Portugal, but the meteorological conditions are expected to change and dissipate by the weekend.