Chief Meteorologist Frank Saunders said: "Strong winds at this time of year can increase the rate of leaf fall which can potentially block drains or culverts and, with the heavy rainfall expected over Friday and Saturday, could well heighten the potential for flooding".
Higher wind speeds will impact all areas of the province, with exposed coasts and hills the worst affected.
In total, 13 counties have an orange weather warning in place - the second highest level of severity - they include: Donegal, Galway, Mayo, Sligo and Clare, Dublin, Louth, Wexford, Wicklow, Meath and Waterford.
"Preparations are well underway to ensure we have engineers and equipment and customer care teams on hand to respond to faults should they come in".
A yellow alert was in place at the beginning of the week, as the city battles gale-force winds and flash floods due to high volumes of rain. Expect the unexpected. Watch out for falling/fallen debris on the road and vehicles veering across the road.
Pembrokeshire County Council is working with multi-agency partners to monitor the situation.
With the storm set to move north during Friday and Saturday, electricity distributor SP Energy Networks has issued advice in case of power cuts in North Wales.
However, it is Friday (October 12) which will see the full force of Storm Callum.
Sioned Warrell, Natural Resources Wales Duty Tactical Manager, said: "The rain could cause flooding, especially in south and west Wales, and we are urging people to prepare themselves". Rain will clear to showers in Northern parts but further heavy rain is likely to spread into Southern and Eastern areas with the ongoing flooding risk.
Natural Resources Wales (NRW) warned that weather conditions at sea could also cause flooding with large waves, strong winds and a tidal surge.
Where flooding may occur there is a chance of delays or cancellations to train and bus services.