Hi there,
The wind displayed on your ND corresponds to the instant wind. It is computed by the IRS after 100 kts.
The computation of the wind direction and force uses the real time difference between the heading and track of the aircraft, as seen by the IRS. Therefore as long as your aircraft is on the ground, the display corresponds to longitudinal component of the wind. Moreover during the take off roll anemometric disturbance may cause an erroneous wind value to be displayed on the ND.
Once airborne, since lateral drift can be measured, the IRS are able to compute and display the wind direction and force.
I hope this helps anwering your question
TFCM