Are the currents shown surface currents or undercurrents?
They are supposed to be surface currents as described here:
However I have not been able to find any information about ocean currents data provided by NESDIS / NOAA.
IMHO this data is rather from OSCAR / NASA
With a 0.25° grid, the resolution of OSCAR model corresponds effectively to 22km as said by Windy (longitudinally at USA latitude).
By the way earth.nullschool.net show the same type of data:
but it is said provided by OSCAR:
In case the data is confirmed to be provided by OSCAR, it must be noted that "The model calculates a surface current averaged over the top 30m of the upper ocean".
Please could you check data/provider of Currents layer for correction or confirmation.