Upper-right: abbreviated geopotential height (this is the last three digits of the height value). If below 500 hPa, value is in meters, otherwise it is in dam.
Wind barb: wind speed in knots and wind direction
Black solid lines: geopotential height each 6 dam analyzed with Barnes algorithm from upper-air observations and first guess model data
Filled color contours with dashed lines: temperature each 4 deg C analyzed with Barnes algorithm from upper-air observations and first guess model data
Decoding time stamp example:
210804/0100
210804/0100: year=2021; month=08 (August); day=04; 1200=12:00 UTC
