The storm is expected to bring heavy rain between 6am on Friday and 6pm on Saturday, particularly over south-facing hills.
A Status yellow wind warning is in place for counties Carlow, Kildare, Kilkenny, Laois, Longford, Offaly, Westmeath, Cavan, Monaghan, Leitrim, Roscommon, Limerick and Tipperary, from midnight on Thursday until Friday morning.
The warning for Cork and Kerry is valid from Thursday 11 October 2018 22:00 to Friday 12 October 2018 09:00.
An orange weather warning will be in place for all coastal counties from 10pm, and will be valid until tomorrow morning.
STV's weather presenter Sean Batty says the north and west of the country will be worst affected as Storm Callum arrives. Gusts 50 to 60 miles per hour are likely in some places, with potential for gusts of 70 to 80 miles per hour around exposed coasts and hills.
"Some exposed locations could see as much as four inches by the end of Friday".
Latest iOS update fixes iPhone charging problems
A bug was causing some of these models to hook up with a slower 2.4GHz Wi-Fi network instead of a faster 5GHz signal. The new software also tackles a WiFi annoyance that some users had been reporting.
Victoria BID raising awareness for World Mental Health Day
World Mental Health Day is organised by the World Health organisation and aims to raise awareness around mental health issues. Schools will also be given help to measure their students' health, including their mental wellbeing, under the plans.
Microsoft's xCloud Gaming Service Will Bring Console Games to Mobile
Project xCloud is created to let you stream games anywhere - whether you're on PC, console, or even your phone . Microsoft plans to begin public trials in 2019 to "learn and scale with different volumes and locations".
On Saturday, areas over high ground could see a further 50 to 80mm of rain.
Very strong winds are predicted, making driving conditions hazardous, especially for the more vulnerable road users, e.g. cyclists, pedestrians, motorcyclists and high sided vehicles.
After the worst of the wind has swept the country, the tail-end of Hurricane Leslie will bring rainfall, raising the prospect of coastal and river flooding.
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.
Wales and the North West could have the heaviest deluge.
Ireland will bear the brunt of the storm, but gusts of 80mph are expected in parts of Scotland, with up to 10cm of rain falling. "There is also a risk that the high winds associated with Storm Callum, combined with high tides, may lead to some coastal impacts due to large waves".
There is also the risk of further severe Southerly winds impinging onto Southern and Eastern coastal areas during the day.