NAM AIR QUALITY DIAGNOSTIC DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1023 AM EDT WED AUG 15 2012


*** The following information pertains to initialization errors
noted on the 12Z NAM that may negatively impact the performance of
the 12Z CMAQ output as used for air quality forecasting.
Specifically, errors that apply to temperature, winds, relative
humidity and precipitation are included. This discussion only
applies to geographical regions of the CONUS where air quality is
currently forecast to be degraded (i.e. CODES:
YELLOW/ORANGE/RED/PURPLE/MAROON). ***


...INTERIOR VALLEYS OF CALIFORNIA...

NO SIGNIFICANT INITIALIZATION ERRORS WERE NOTED.


...SERN CA/AZ/NM/WESTERN TX...

NAM INITIALIZED SURFACE TEMPERATURES WERE 6 TO 12 DEGREES TO COOL
ALONG THE CA/AZ BORDER AS WELL AS SOUTHERN AZ. INITIALIZED SURFACE
TEMPERATURES WERE 5 DEGREES TOO COOL ACROSS EXTREME WESTERN
TEXAS...NEAR EL PASO.


...SNAKE RIVER VALLEY OF EASTERN IDAHO/NORTHERN WASATCH IN UTAH...

NAM INITIALIZED SURFACE TEMPERATURES AVERAGED 5 TO 10 DEGREES TOO
COOL IN THE SNAKE RIVER VALLEY AS WELL NEAR SALT LAKE CITY. NAM
INITIALIZED 10-METER WIND SPEEDS ACROSS THIS AREA WERE 5 TO 15
KNOTS TOO LOW IN SOME AREAS.


...WASHINGTON STATE...

NAM INITIALIZED SURFACE TEMPERATURES WERE AS MUCH AS 5 DEGREES TO
COOL...PARTICULARLY IN THE LOWER ELEVATIONS WEST OF THE CASCADES.


...COLORADO...

NAM INITIALIZED SURFACE TEMPERATURES WERE 7 TO 13 DEGREES TOO COOL
IN PORTIONS OF COLORADO...PARTICULARLY AROUND DENVER AND COLORADO
SPRINGS.


...CENTRAL/SOUTHERN PLAINS TO MIDWEST AND OHIO RIVER VALLEY...
...SOUTHEASTERN STATES...
...MID-ATLANTIC/NORTHEAST...

NO SIGNIFICANT INITIALIZATION ERRORS WERE NOTED.


RYAN