Phoenix Forecast
AQI Scale
Air Quality UPDATED: Sun. Jun 24, 2018 7:20 AM
This report is updated Monday through Friday and is valid for areas within and bordering Phoenix, Arizona
Today | Sunday 6/24/2018
87
Ozone
MessageHealth Statement:Unusually sensitive people should consider reducing prolonged outdoor exertion.
Tomorrow | Monday 6/25/2018
108
Ozone
MessageHealth Statement:Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.
Extended | Tuesday 6/26/2018
101
Ozone
MessageHealth Statement:Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.
Extended | Wednesday 6/27/2018
93
Ozone
MessageHealth Statement:Unusually sensitive people should consider reducing prolonged outdoor exertion.
Extended | Thursday 6/28/2018
84
Ozone
MessageHealth Statement:Unusually sensitive people should consider reducing prolonged outdoor exertion.

Air Pollutant Breakdown
Pollutant Yesterday
6/23/2018
Sunday
6/24/2018
Monday
6/25/2018
Tuesday
6/26/2018
Wednesday
6/27/2018
Thursday
6/28/2018
O3 93 87 108 101 93 84
CO 5 8 9 9 8 7
PM10 61 45 57 60 59 57
PM2.5 40 28 31 30 30 29
O3 = Ozone, CO = Carbon Monoxide, PM10 = Particles 10 microns and smaller, PM2.5 = Particles smaller than 2.5 microns

Synopsis & Discussion
Forecaster: -M. Pace
The Phoenix valley exceeded the federal health standard for ozone on Friday with an AQI of 101 and yesterday (Saturday), came close at 93 AQI.

Today, high pressure is located west of Arizona as a trough brushes the state to the north. This pattern should allow for enough breezes at the surface and just above the surface to enable ozone levels to drop slightly from what was observed yesterday.

Monday and Tuesday, the broad area of high pressure will slide eastward and be over Arizona. This will result in another episode of calm winds and clear skies which is an ideal pattern for ozone formation here in the Valley of the Sun. As a result, an Ozone High Pollution Advisory is in effect for Phoenix tomorrow (Monday) with another advisory possible on Tuesday.

By Wednesday into Thursday, the ridge continues moving east and will be center over New Mexico as a trough drops down the West Coast. As a result, southwesterly winds will be on the rise. With Wednesday being more of a transition day, ozone will likely be elevated so an Ozone Health Watch will be possible. By Thursday, ozone levels are forecast to drop below health watch or advisory levels.

As for PM-10 (dust) expected spikes in the morning with reduced readings by the afternoon given how warm afternoon high temperatures will be through the forecast period.

What Flag Should I Fly?
Sunday: Yellow
Monday: Orange

Useful Links
- Subcribe to the Forecast
- Yesterday's Monitor Data
- Year-to-Date Reports
- Maricopa County Air Monitoring Site
- Read current issue of "Cracking the AQ Code"


Main Office
1110 W.Washington Street
Phoenix, AZ 85007
P: 602.771.2300
azdeq.gov