The rain will be heavy and preceded by sleet and snow across the north and east and may give accumulations over high ground.
The warning is valid from Thursday, December 7 4pm to 6pm Friday, December 8.
Last night Met Eireann issued a status yellow snow-ice warning for the entire country which will come into force later today.
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Tanto que retomo meu trabalho no Hospital Universitário e não participei do processo de escolha do sucessor. Durante entrevista coletiva à imprensa, ele informou que pediu demissão por motivos particulares.
Met Éireann says there'll be scattered snow showers later on Thursday, overnight and into Friday.
Forecasters warn of snow showers over the evening, as well as on Friday. As a result people are also advised to be careful on icy roads and footpaths. Widespread frost early and late.
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No seminário "As lições de Pedrógão Grande", em Coimbra, Viegas afirmou que existiu "demora no socorro e no tratamento médico".
"The showers will turn increasingly wintry with falls of hail and snow - especially in the north, and a few will push further south this evening. Lowest temperatures -2 to +3 degrees, coldest inland in the north".
"There will be a cold spell for the next ten days".
Temperatures will drop to zero or below zero tonight for the bulk of the country, he said, but will hit as low at minus 3C in the northwest tomorrow.
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While both sides have called for a United Nations peacekeeping force in eastern Ukraine, they disagree on the terms of its deployment, and there was no sign of progress at Thursday's meeting.
Meanwhile, the Road Safety Authority has warned motorists to expect the unexpected with high winds and icy conditions.