Dark smoke from heavy fuels in the upper elevations of Pima Canyon obscures the rising sun during the Bighorn Fire in the Santa Catalina Mountains in Coronado National Forest north of Tucson on June 9, 2020.

 Rick Wiley / Arizona Daily Star

A wildfire that began near Pusch Ridge as a 200-acre blaze has grown to more than 10 times in size and could send smoke drifting into Tucson as wind directions change, fire officials said Monday.

"Those with smoke sensitivity are urged to take adequate precautions," a federal news release said Monday.

Pima County's environmental department said the impact may be felt most keenly in north Tucson, Oro Valley and Catalina.

The county has issued air pollution health watch urging children, older adults and those with respiratory issues to avoid the outdoors when smoke is in the air.

The Bighorn Fire, which began June 5, covered about 2,300 acres by midday Monday, June 8, the news release said.

The Bighorn Fire glows as it burns into Pima Canyon in the western reaches of the Santa Catalina Mountains above Tucson, Ariz., just after sunset June 8, 2020. During its third day, the lightning sparked wildfire chewed a wind driven path east and higher into the range.

The lightning-induced blaze, visible from much of the city and surrounding areas, is about 10% contained and additional resources have been added to the firefighting team, said Heidi Schewel, spokeswoman for the Coronado National Forest.

At last report, the fire was moving northeast toward Table Mountain and had reached the elevations of Pima Canyon, the news release said.

The number of personnel assigned to fight the fire has more than doubled, from 80 initially to more than 175 as of Monday. They include five hot shot crews, 12 engines of different types, nine water tenders and four helicopters equipped to drop water or fire retardant.

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