Visual Reference and Comparison of ECMWF Operational, ERA5, ERA-Interim, and NOAA Daily Weather Map 500 mb Height and Winds for 2016-01-01 12:00:00 UTC
Notice the low pressure systems (cyclones) south southeast of the Alaska Peninsula, and north of Hudson Bay. There is also a cut-off low developing over northern California. A high pressure anticyclone spins clockwise over Washington state and southern British Columbia. A high pressure ridge extends from east of the Caribbean to the Pacific, and the polar jet stream is clearly visible over north central Canada (up to 82 knots, 94 mi hr-1, 42 m s-1). Vector wind grid point locations will vary from image to image. Geopotential height contour values are the same in all figures. (ECMWF results computed by CISL RDA from spectral vorticity and divergence, and spectral geopotential.)
2016-01-01 12:00:00 UTC ECMWF Operational IFS CY41r2 5120x2560 (N1280, T1279, 7.8 km, 0.07°) 500 mb vector U and V winds (in m s-1) computed from spectral vorticity and divergence. Corresponding geopotential height (x10 gpm) computed from spectral geopotential. Cylindrical equidistant projection.	2016-01-01 12:00:00 UTC ECMWF ERA5 IFS CY41r2 1280x640 (N320, T639, 31 km, 0.28°) 500 mb vector U and V winds (in m s-1) computed from spectral vorticity and divergence. Corresponding geopotential height (x10 gpm) computed from spectral geopotential. Cylindrical equidistant projection.
2016-01-01 12:00:00 UTC ECMWF ERA-Interim IFS CY31r2 512x256 (N128, T259, 78 km, 0.7°) 500 mb vector U and V winds (in m s-1) computed from spectral vorticity and divergence. Corresponding geopotential height (x10 gpm) computed from spectral geopotential. Cylindrical equidistant projection.	2016-01-01 12:00:00 UTC NOAA Daily Weather Map (produced with GFS-GDAS/FNL) 1440x720 (27.7 km, 0.25°) 500 mb vector U and V winds (wind barbs indicate knots) with corresponding geopotential height (x10 gpm). Lambert conformal projection. 1 m s-1 = 2.23694 mi hr-1 = 1.94384 knots.