[ADEQ Forecasts] ADEQ AIR QUALITY FORECAST FOR FRIDAY, DECEMBER 12, 2008

[forecasts@lists.azdeq.gov]

http://www.azdeq.gov/ensemble.pdf

For transportation alternatives:
http://www.valleymetro.org

Health message for Thursday December 11: Unusually sensitive people
should consider reducing prolonged or heavy exertion.

Health message for Friday December 12: Unusually sensitive people should
consider reducing prolonged or heavy exertion.
 
Synopsis and Discussion
A PM-2.5 HEALTH WATCH REMAINS IN EFFECT THRU THURSDAY DECEMBER 11
A strong (7-8 deg C) and tall (~3300') surface-based radiation inversion
formed overnight and latest ACARS sounding data reveals that the best
Valley mixing depth today will be near 3K' with POOR to MARGINAL
dispersion.  Although no large spikes in fine particle (PM-2.5)
concentrations have occurred during the past few overnight periods,
latest data from the Durango monitoring site indicates that readings are
much above those of 24 hours ago and peaked near 30ug/m3 at 10:00 a.m.
Since increasing and thickening high clouds will tend to inhibit
vertical mixing today as well, today's PM-2.5 Health Watch will remain
in effect thru midnight.  Another stagnant day is likely to occur on
Friday; the approach of a weak upper level disturbance, however, should
improve dispersion a bit due to some cooling aloft and perhaps a bit
more wind.  A change to windy and potentially wet conditions will begin
on Saturday as a large and powerful trough in the mid-latitude storm
track - guided by a 180+knot polar front jet stream - develops over the
western U.S.  -Reith  

**********************************************************************
NOTICE: This e-mail (and any attachments) may contain PRIVILEGED OR 
CONFIDENTIAL information and is intended only for the use of the specific 
individual(s) to whom it is addressed.  It may contain information that is 
privileged and confidential under state and federal law.  This information 
may be used or disclosed only in accordance with law, and you may be 
subject to penalties under law for improper use or further disclosure of the 
information in this e-mail and its attachments. If you have received this e-
mail in error, please immediately notify the person named above by reply e-
mail, and then delete the original e-mail.  Thank you.