We compared footage captured by our ABC30 skycams at various locations in the Central Valley - and the difference in one week is stunning.
For the last 10 days, residents in Fresno and surrounding counties have been living and breathing in dangerously polluted air and it's likely to continue.
RELATED: Unhealthy air quality continues in the Valley as smoke expands to other states
Wildfires burning across California have caused the Valley's air quality to plummet to dangerously unhealthy levels, the San Joaquin Valley Air Pollution Control District says.
Where earlier there were clear skies and panoramic views, there is now only a dirty grey haze swallowing up the horizon and in some cases, everything in sight.
At another time of the year, it could easily be mistaken for mist and fog. But now, at the height of summer, there's no disguising it - smoke, soot, ash and other particulate matter. It's not uncommon to see this toxic mix falling from the sky, as many ABC30 viewers have filmed and sent us, or to find a layer of it coating cars.
Since the air quality worsened, paramedics and firefighters say they've noticed a spike in the number of people calling for emergency services.
Several residents have told Action News they're having trouble breathing, or that their eyes and throat are burning after spending some time outdoors.
Alarmed medical experts have urged residents, especially those with respiratory conditions, to stay indoors if they can.
But some are not so fortunate.
The unhealthy air, combined with the extreme heatwave sweeping California and the risk of contracting COVID-19 are posing a triple threat to many essential Valley workers like farm laborers who can neither avoid working outdoors, nor always keep a 6-feet distance from coworkers.
But the Valley air district has some hope to give desperate residents - it says the potential for windy conditions at times this week could help disperse the smoke a bit.