Crews took advantage of cooler temperatures and higher humidity settling over the fire area on Monday, but there was still no containment on the northeast side of the fire, officials said.
The Mosquito Fire is among numerous blazes currently burning in Western states, blanketing the skies with smoke and spurring air quality alerts across much of California, Washington, Oregon and Idaho.
Smoke from the Mosquito Fire advanced across state lines into Nevada, where a time-lapse video posted by the National Weather Service in Reno, showed a wall of smoke crashing into the state Sunday. The smoke created unhealthy to hazardous air quality in the region and was expected to linger in the Tahoe Basin and Reno area through Monday, the weather service said.
Wildfire smoke can hurt the eyes, irritate the respiratory system, and worsen chronic heart and lung diseases, according to the Centers for Disease Control and Prevention. The smoke can be particularly dangerous for children, people with heart or lung disease, older adults and pregnant people.
Numerous wildfires ravage parched lands in the West
Crews in the Sierra Nevada mountains were among several engaged in grueling firefights against raging wildfires this week.
Widespread high temperatures in the West — coupled with low humidity and spurts of lightning strikes — continue to exacerbate wildfire conditions, fire center officials said.
Drought-stricken Western states are home to large swaths of dry brush that can transform into fuel for infernos, particularly in mountain communities.
CNN’s Taylor Romine contributed to this report.