It was so hazy, the Santa Clara County Public Health Department issued a health advisory for the most vulnerable people to stay indoors.
You could see the problem easily from Mt. Hamilton looking west across the Santa Clara Valley. The smoke was thick and unhealthy.
So noticeable that Monica Perez and daughter Miranda changed their afternoon play plans.
"Just because of what's going on, you never know what we're breathing," said Perez.
Miranda on the other hand, wasn't too worried.
The county Health Department sided with mom, and county health officer Dr. Marty Fenstersheib, says the warning is not just for children, but also for those with respiratory problems or older adults.
"If you're a jogger, I'm a jogger and I didn't run this morning, or if you're a biker, we are asking people to not do that today because it's not very healthy and it's not good for your lungs," said Dr. Fenstersheib.
Over at the county health building, Jennifer Owens was worried about her first grade daughter Destiny.
"She has chronic asthma and needs different medications to inhale. This smoke and heat, different things cause her to have breathing problems," said San Jose resident Jennifer Owens.
Jennifer didn't need to worry so much her little girl. The San Jose Unified District took one smell of the air and looked at the sky, and left it up to the individual schools whether to have any strenuous outdoor P.E.
At Trace elementary, the bad air cost the school good money. No strenuous activity meant no Jump for the Heart fundraising event.
"Because it is a strenuous activity of 30 minutes of straight jump rope, we were asked not to have P.E. activities, but we will reschedule it for next Friday," said Trace Elementary principal Mary Martinez.