"Northwesterly winds" means winds that blow from the northwest direction, coming towards you from the northwestern part.
Full definition
Typically, classic nor'easter s that strike southern New England as well as the Mid-Atlantic do so when the confluence zone, or area of strong west - to -
northwesterly winds well north of the storm system, is located further to the north and west, across Quebec, compared to this setup.
The shape and location of the Rockies help to cause a persistent wave in the Jet Stream, with a trough in over eastern North America which brings cold continental air,
via northwesterly winds, to northeastern North America, and a crest over the eastern north Atlantic and western Europe which brings warm maritime air, via southwesterly winds, to northern Europe.
San Miguel is the westernmost island, and as a result receives the brunt of
the northwesterly winds, fog, and severe weather from the open ocean.
The cool, dry westerly and
northwesterly winds — driven by the East Asian winter monsoon (pdf) circulation — typically blow pollutants away from the city.