Storm Eunice - the second of two storms in just a few days - will sweep across Northern Ireland today having already made landfall in the Republic of Ireland this morning, with gusts of more than 81 mph being reported in Counties Kerry and Cork.
Snow and sleet has already been reported in westerly areas of Northern Ireland.
The yellow warning in Northern Ireland is in place until 6pm today, with disruption to travel possible.
Forecasters say that there will be outbreaks of rain and snow this morning, with the snow predicted to be heavy on high ground.
They say it will become brighter this afternoon with wintry showers. It will feel cold in the strong to gale force north to northwesterly winds.
The maximum temperature will be 5 C.
Tonight there will be frequent wintry showers, which will be heavy at times. The showers and strong winds will ease later in the night and skies will clear to lead to some frost and icy patches. The minimum temperature will be 0 C.
What to expect with a yellow weather warning for snow
* A chance of travel delays on roads, possibly with stranded vehicles and passengers, along with delayed or cancelled rail and air travel.
* A slight chance that some rural communities could be temporarily cut off.
* A small chance that power cuts will occur and other services, such as mobile phone coverage, may be affected.