[Ref US AIM Section 3 Airport Operations 4-3-7]

How do pilots know if there is low-level wind shear (LLWS) near airport? (in USA)

Ans: Controllers (ATC) will provide low-level wind shear (LLWS) information to pilots by giving the pilot the airport wind followed by the boundary wind.

EXAMPLE−
Wind shear alert, airport wind 230 at 8, south boundary wind 170 at 20.

What’s the different between “Wind shear alert” and “microburst alert” ? (US)