LATEST: The bad weather has resulted in a number of crashes across the city including a car crashing into a pole on the Old Youghal Road, by St Josephs Church.
In Ballyvolane there are reports of a “very serious” crash by the Applegreen garage on the North ring road.
Cork is experiencing hailstorms along with thunder and lightning as Storm Dennis rumbles on.
EARLIER: There are unconfirmed reports of blackouts in various spots across the city, including some of the shops on Opera Lane. Officially there are outages in Whitechurch and Lissarda.
There are also reports of a number of collisions around the city and county, as weather conditions and fallen trees make driving conditions hazardous.
Met Eireann issued a Status Orange weather warning for Cork yesterday with southwest winds expected to reach mean speeds of 60 to 80 km/h with severe gusts of up to 120km/h. The strongest winds will be on exposed hills and coasts, with a risk of coastal flooding.
The warning has been in place since 10am this morning and is there until 10pm tonight.
The rest of today is expected to be very windy and stormy with sunny spells and widespread heavy thundery showers along with the added risk of hail.
Thunder is going to be frequent in Cork for the afternoon and temperatures will be between six to nine degrees.
Tonight, the weather is expected to continue being windy and stormy, with strong to gale force and very gusty southwest winds. Later in the night winds will ease somewhat, but will continue fresh to strong and gusty. Heavy showers of rain and hail will continue with a risk of thunder. Lowest temperatures of two to four degrees, with a touch of frost in more sheltered spots.
Monday will be a cold, bright, blustery day with sunny spells and widespread heavy showers, again with a risk of hail and thunder. Some of the showers turning wintry over high ground. Highest temperatures of 5 to 8 degrees with mostly fresh, gusty westerly winds, strong on coasts.
EARLIER: Dennis continues to hit Cork, with a Status Orange warning in place until 10pm.
A Yellow rainfall and wind warning has been in place nationwide since yesterday, with the storm hitting the country since early morning on Saturday.
The warning has been upgraded to Orange for Cork from 10am until 10pm today, with conditions set to deteriorate throughout the day.
Met Éireann says: "Southwest winds with mean speeds of 60 to 80km/h with severe gusts of up to 120km/h, strongest on exposed hills and coasts, with a risk of coastal flooding."
Over the last 24 hours, there have been fallen trees on the N22 in Cork, and at Whitehall Cross, Cloyne and near Crossbarry.
Power outages were logged in areas across east Cork, with power restored to hundreds of homes yesterday evening.
Met Éireann says there will be spells of heavy, thundery rain, which will lead to some flooding.
Speaking ahead of Storm Dennis, forecaster Deirdre Lowe said:
"There is a risk of flooding in parts, especially near rivers that are very high at the moment and coastal areas in the very strong and gusty, south to south-westerly winds.
"Winds are expected to pick up further on Sunday, especially on the west coast as Storm Dennis lingers over the country."
However, she said Sunday is when Storm Denis will hit hardest, adding: "Sunday we're going to have the worst of the winds."
The AA's Barry Aldworth is urging anyone out on the road to drive carefully and sensibly.
Mr Aldworth said: "The most important tip we always give people is to reduce your speed, allow extra distance between yourself and other vehicles in front of you.
"Only attempt to drive through flashes of water in the road if you feel comfortable that you know the level of the water. If you are unsure, it's better to try and find another way around it. Drop your gears, drive through it slowly."