Natural Resources Wales (NRW) warned that weather conditions at sea could also cause flooding with large waves, strong winds and a tidal surge.
Widespread travel disruption and flooding is predicted across the country as conditions deteriorate from Thursday into Friday morning, with a series of Met Office weather warnings already in force.
In wet weather drivers are urged to slow down if the rain and spray from vehicles is making it hard to see and be seen and remember that stopping distances will be at least double in wet weather, keep well back from the vehicle in front, and ease off the accelerator and slow down gradually if the steering becomes unresponsive. If it drifts further east, we would be in for stronger winds.More news: Nokia 3.1 Plus, Nokia 8110 4G launched in India
The effects of Storm Callum are expected from 10 tonight - when the orange weather warning kicks in for counties Cork and Kerry.
Winds that could top 80mph are forecast to batter western Scotland on Friday followed by downpours across more of the country on Saturday. There are also risks of coastal flooding, and the warning is in place from 10pm Thursday until 12pm Friday. Lowest temperatures of 8 to 10 degrees will occur early in the night. This is also set to elapse at 9am on Friday morning. The Western Isles could get another hit of severe gales and high gusts on Saturday afternoon, again not as stormy as on Friday but worth bearing in mind. It means southern parts of Wales especially are at risk of being flooded.
The strongest winds are likely in western Ireland, although North Western parts of the United Kingdom can expect severe gales.More news: Michael: Most violent United States hurricane since 1969
A yellow warning for wind is in place across the west coast of Scotland, including Glasgow and parts of the central belt, throughout Friday.
"Possibly damaging and disruptive southeast winds will veer southwest after the passage of this front, with the strongest of the winds set to impact coastal areas".
A spokesperson said the western county was experiencing a period of "very high astronomical spring tides".More news: Selena Gomez receiving treatment after suffering emotional breakdown
A combination of winds up to 60 miles per hour and heavy rainfall are set to make driving conditions hazardous - including along the coast at times of high tides. "Elsewhere, however, the winds should remain below warning thresholds".