This alert applies mainly to higher parts of Connacht and Ulster from about 0400h to 1500h Thursday 23rd, but could briefly be extended into other parts of the country.
Much colder air accompanied by strong westerly to northwesterly winds that may gust to 90 km/hr will produce wintry showers especially on higher terrain (above 150 metres a.s.l.) in the northwestern counties, notably Donegal, Derry, Tyrone, Leitrim, Sligo, Mayo, higher northern parts of Galway and Roscommon.
These conditions will likely be "hit or miss" and not continuous, but be aware especially if planning to drive any longer distances that conditions may at times be quite poor in sleet, hail or even snow blowing across open countryside.
Intervals of bright sunshine will present their own hazards especially if your windshield is gummed up with the residue of these recent wintry showers.
Many of the larger urban areas will probably escape this first onslaught of a wintry period to come without much if any action, but be prepared if you're driving in the northwest tomorrow. These conditions could reappear at times on Friday in much the same parts of the country, although with perhaps somewhat lower wind speeds.
A longer-time-scale alert may be required for Monday night or Tuesday as there are some signs of an organized frontal band without much warmth to prevent a wintry mix of precip developing then. This might be more of an east Ulster to Leinster event, once again more likely to produce at higher elevations. Stay tuned on that one.