Raw data of NWS winds aloft plots

Does anyone know if it is possible to access the raw data that is used
for the winds aloft plots on aviationweather.gov? At first I assumed
it was an interpolation of the classical FD text data. But then I
realized that the graphical plots have a finer time increment than the
FD text data. It is quite possible that they might be interpolating in
space and time, but I would like to know if there is another data set
that I am not aware of.