NAM AIR QUALITY DIAGNOSTIC DISCUSSION
NWS HYDROMETEOROLOGICAL PREDICTION CENTER COLLEGE PARK MD
1029 AM EDT THU AUG 23 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). ***

...OHIO VALLEY/MID-ATLANTIC STATES...

NO SIGNIFICANT INITIALIZATION ERRORS.

...MIDWEST...

NO SIGNIFICANT INITIALIZATION ERRORS.

...SOUTHEAST...

NO SIGNIFICANT INITIALIZATION ERRORS.

...SOUTHERN PLAINS AND WESTERN GULF COAST...

THE NAM DID NOT DEPICT OR WAS TOO SLOW TO DEPICT...THUNDERSTORMS
THAT WERE OBSERVED MOVING ONSHORE THIS MORNING. THE THUNDERSTORMS
WERE OBSERVED ALONG THE IMMEDIATE GULF COAST FROM SOUTHWEST OF
GALVESTON TO SOUTH OF LAKE CHARLES. OTHERWISE...NO SIGNIFICANT
TEMPERATURE OR WIND ERRORS WERE NOTED IN THIS REGION.

...INTERMOUNTAIN POPULATION CENTERS INCLUDING BOISE...SALT
LAKE...AND PARTS OF COLORADO...

THE NAM INITIALIZED TEMPERATURE REASONABLY WELL...WITHIN 5 DEGREES
OR LESS OF OBSERVATIONS...OVER THE COMPLEX TERRAIN IN COLORADO AND
NORTHERN UTAH. THE MODEL INITIALIZED 5 TO 10 DEGREES TOO COOL IN
THE LOWER SNAKE RIVER VALLEY NEAR AND WEST OF BOISE.

...SOUTHERN ARIZONA TO SOUTHERN CALIFORNIA AND THE CENTRAL
VALLEY...

THE NAM INITIALIZED SURFACE TEMPERATURE 5 TO 7 DEGREES TOO COOL IN
A RELATIVELY SMALL AREA OF THE FOOTHILLS NEAR PALM SPRINGS.
ELSEWHERE IN THIS REGION THE MODEL WAS WELL INITIALIZED.

...INTERIOR VALLEYS OF NORTHERN CALIFORNIA OVER TO RENO NEVADA...

THE NAM INITIALIZED 10 TO 15 DEGREES TOO WARM IN SOME OF THE
MOUNTAIN VALLEYS WEST OF RENO...SUCH AS NEAR LAKE TAHOE. ELSEWHERE
IN THIS REGION...THE MODEL INITIALIZED WELL.

BURKE