NAM AIR QUALITY DIAGNOSTIC DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER CAMP SPRINGS MD
1004 AM EDT TUE AUG 09 2011
 
*** 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 SOUTHERN CALIFORNIA...
...DESERT SOUTHWEST...

THE NAM INITIALIZED AS MUCH AS 10-15 DEGREES TOO COOL NEAR THE
MOUNTAINS...AS A RESULT OF TERRAIN RESOLUTION.


...NORTHERN WASATCH FRONT...

THE NAM INITIALIZED 10-15 KNOTS TOO LIGHT WITH THE SURFACE WINDS
OVER THE REGION.


...CENTRAL OHIO VALLEY...
...MID ATLANTIC STATES...
...CAROLINAS...

NO SIGNIFICANT MODEL INITIALIZATION ERRORS WERE NOTED OVER THESE
REGIONS.


CISCO



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