The Irish Coast Guard has warned lives could be lost as it appealed to the public to avoid coastal areas over the next 36 hours.
Flood and storm alerts have been issued for parts of the west of Ireland and the Coast Guard and other emergency services are braced for tumultuous conditions.
All vessels off the west and south coast of Ireland have been advised to seek shelter after forecaster Met Eireann issued two wind warnings for most of the country on Monday and Tuesday.
Coast Guard director Chris Reynolds said: "The storm has the potential to lead to a loss of life. We have had a number of deaths this year when members of the public who would not have been used to being on exposed rocks or piers are suddenly overwhelmed by a wave and pulled into the sea.
"There are no rogue waves, only unpredictable ones. So please exercise extreme caution over the next 36 hours, particularly if you are with young children.
"The seas will be at their most treacherous in the afternoon on the east coast, and early evening on the south and west. Our message is stay back, stay high and stay dry."
Co Clare on the west coast has been among the hardest hit by previous severe conditions.
Emergency agencies are warning of a significant risk of localised flooding in all parts of the county due to a combination of strong gale to storm force southerly winds, heavy rainfall, high tides and already saturated ground.
Motorists also are being advised to avoid unnecessary travel on Tuesday night and during Wednesday as all roads are at risk of being flooded.
The council warned that water levels along the Lower River Shannon are likely to increase further in the coming days.
Belfast Coast Guard posted on social media: "As Storm Frank bears closer to us, Coastguard would like to remind the public to avoid exposed coastal areas and cliff tops.
"Wave dodging may look fun, but the power of the water is more than enough to knock you off balance."