300-200 hPa layer-mean potential vorticity (shaded in PVU; yellow=-2, orange=-4, red=-6, pink=-8) and wind (standard barbs in knots in white) and 850-700 hPa layer-mean potential vorticity (black contours and shaded according to the color bar in PVU) and wind (standard barbs in knots in black).
These plots are derived from the NCEP GFS analyses and forecasts on a 0.25x0.25o latitude-longitude grid.