From Monday night to perhaps Wednesday we are in for some raw weather as a strong Northwesterly flow introduces some polar air to Western shores. Because of the strong gradient it will quickly pass over the Warmer Atlantic and get a slight Maritime mix at lower levels but there should be less modification of the airmass.
This has all the ingredients of thunder activity and the spawning of comma features.
A Polar Low is not out of the equation as a capsule of -40 air at 500mb gets drags off Greenland. There is some 510 true polar dam air at the beginning that helps to feed this North westerly flow.
An interesting mix of heavy rain sleet and snow showers especially over higher ground is very likely and combined with the strong winds would give whiteout conditions at times. So Thundersnow and blizzards are in there for parts of higher Ulster and Connaught. Munster could see something similar AND parts of the Midlands in the strong flow.
Very interesting setup for the North and Western half of Ireland. As mentioned a Strong gradient so Midlands could see some wintry falls too.
This is a watch for sure. There's also a strong risk of travel disruption to areas mentioned.