John Curtin, Executive Director of Flood & Coastal Risk Management at the Environment Agency, tweeted this week: "Latest intel on #StormDennis - sadly looking at 420 flooded but 18,500 properties defended - both numbers likely to rise."
Only a week prior to Storm Dennis, the UK was lashed by Storm Ciara, which in some regions blasted the UK with 97mph winds.
According to Mr Curtin, some 800 properties were flooded during Storm Ciara, almost double the current tally for Storm Dennis, but this figure is likely to increase as hundreds of flood warnings and alerts have been issued for today (Tuesday).
As of 8am on Tuesday, 225 flood alerts are in place across England, meaning to prepare for possible flooding.