[ADEQ Forecasts] ADEQ Daily Air Quality Forecast - Wednesday, September 28, 2011

[forecasts@lists.azdeq.gov]

Health message for Tuesday September 27:  Unusually sensitive people
should consider reducing prolonged or heavy exertion outdoors.

Health message for Wednesday September 28:  Unusually sensitive people
should consider reducing prolonged or heavy exertion outdoors. 


Synopsis and Discussion
OZONE:  Despite weather conditions to the contrary, local ozone levels
cratered again on Monday and it appears that there is an ozone precursor
imbalance that is strongly curtailing production.  Pretty difficult to
forecast when this situation will change (a thunderstorm outflow
boundary would do it), but in the meantime have lowered the forecast AQI
values to better reflect the current circumstances. 
PARTICLES:   Overnight inversion formation along with relatively light
winds contributed to some hourly PM-10 (coarse particle) concentrations
above 100ug/m3 at several monitoring sites this a.m. including Durango,
West Forty Third, and Buckeye where the highest reading of 197.9ug/m3
occurred.  A return of summer monsoon moisture to the Valley does not
look likely the next few days.  However, tropical moisture from now
Hurricane Hilary may bring showers and thunderstorms to the Phoenix
metro area by Friday along with a chance for gusty winds and blowing
dust.  Until then, relatively light westerly breezes during the
afternoons will be the rule thru Wednesday becoming southeasterly on
Friday.   


For more information, please visit our Web page:
www.azdeq.gov/environ/air/ozone/ensemble.pdf 

For transportation alternatives:
www.valleymetro.org 


If you have any questions or comments regarding this forecast please
contact:

Arizona Department of Environmental Quality
Office of Communications
1110 W. Washington St., Phoenix, AZ 85007
(602) 771-2215
ms15@azdeq.gov