Snow showers are expected to develop from Wednesday evening lasting into Thursday.
These, combined with strong winds, could lead to locally very poor travel conditions.
Wind gusts up to 55 mph are expected in exposed coastal areas and on hills in association with snow showers, leading to temporary blizzard conditions.
As well as reduced visibility, 2-5 cm of snow could accumulate anywhere within the warning area, with 10-20 cm possible above 300 m.
Lightning may accompany the heaviest showers, with potential disruption to power supplies as a consequence.
Be aware of the potential for disruption to transport due to lying and blowing snow.