SMOKE FROM CALIFORNIAN wildfires has become entangled with a subtropical storm that will hit Ireland this evening.

The tail-end of Storm Ernesto, which formed over the North Atlantic last weekend and became a subtropical storm earlier this week, will bring a spell of heavy rainfall to Ireland and the United Kingdom overnight.

Met Éireann has issued a status yellow weather advisory for all counties, valid from 8pm tonight until 4am on Sunday morning.

Storm Ernesto is visible as the white mass of the west coast of Ireland. Met Éireann Met Éireann

Ernesto may bring short but heavy or intense bursts of rainfall in places, with a risk of spot flooding.

While it is not expected to be a severe storm, it does have one unusual characteristic – it’s bringing smoke, visible from space, in its wake.

It’s not yet clear how this smoke will manifest itself in Ireland, some of which is already in the atmosphere over Europe, aside from being visible in satellite imagery.

Smoke from wildfires in California, some 8,000 kilometres away on the western coast of the United States, has drifted across to the east coast and onacross the Atlantic.

Weather.com says the plume is located high in the atmosphere, and its unusual path was discovered using a model normally used to forecast the origin of Atlantic air masses.

In images released by the National Oceanic and Atmospheric Administration (NOAA) in the United States, the smoke plume is visible being dragged across the Atlantic by Storm Ernesto.

NOAA has put together this GIF to show the system in action.

NOAA Satellites / Twitter NOAA Satellites / Twitter / Twitter

The same haze is visible here – centre and far right – in the latest GOES-East satellite imagery.

GOES-East / NOAA GOES-East / NOAA / NOAA

Here’s further modelling suggesting how the smoke travelled so far (click here to view on mobile)

Sky News, citing forecasters, reports that you may even be able to smell smoke when Storm Ernesto hits, and some soot may be detectable.

However, it’s not clear if that will be the case.

Met Éireann was unable to confirm whether these tangible effects of the smoke would be present in Ireland, and said that their day-to-day forecasting operations they wouldn’t look into this kind of development, instead ‘focusing on predicting the weather’.

California has been hit with the largest wildfires in the state’s history, with firefighters still battling several blazes.

The wildfires have left at least nine people dead, including four firefighters, and forced tens of thousands of residents to abandon their homes.

As many as 14,000 firefighters from around the country and abroad are involved, as well as about 1,000 National Guard personnel supporting wildfire operations in California, with another 450 in Oregon and 170 in Washington state.

Additional reporting by AFP