NGM AND THE SURFACE PATTERN
OVERDEVELOPS SURFACE LOWS OVER LAND ESPECIALLY TO THE LEE OF THE ROCKIES
UNDERDEVELOPS LOWS OVER WATER
HAS NORTHERLY DISPLACEMENT ERROR OVER ROCKIES AND IMMEDIATELY IN THEIR LEE
HAS BIG PROBLEMS HANDLING ARCTIC AIR MASSES (ESPECIALLY ALONG THE FRONT RANGE OF MOUNTAIN RANGES)