Rain and winds of up to 70mph could continue to batter northern England over the Christmas period.
Storm Eva could bring further misery to Cumbria, where some areas are dealing with the aftermath of flooding for the third time in a month.
Appleby, Glenridding, Keswick and Kendal were all hit after rivers burst their banks on Tuesday.
Environment Secretary Liz Truss said military staff and 700 Environment Agency workers would support residents.
She said they would be "looking at what the potential scenarios are".
Speaking to the BBC after chairing a meeting of the government's emergency committee Cobra, Ms Truss said: "We are still too far out to have an exact prediction of the weather but we do know there will be further storms, probably on Boxing Day so we are making sure we have all the resources ready to go should they be needed."
She also said local councils are helping residents find accommodation and said the government will provide £60m for repairs.
Ms Truss said: "It's a terrible situation for people and it couldn't have happened at a worse time of year and we have got every sympathy for those who are suffering."
An Environment Agency spokesman said: "We will issue further flood alerts and warnings if required."
Roy Ashley, whose garage business and home in Appleby have been damaged once again, said the flooding had destroyed lives.
He said: "It has taken people's homes. Some people have lost businesses."
His wife Charlotte said: "No-one's ever seen this, it's unbelievable.
"The water two weeks ago was above my head in the garage - you can't deal with that kind of thing."
Hundreds of properties were flooded when Storm Desmond brought a record amount of rainfall during the weekend of 5 December.
Four days later there was a further deluge, in which Glenridding was particularly badly hit.
Speaking about the latest flooding, Appleby resident Sarah McKay said: "It's just before Christmas and everybody has already lost everything. It's terrible."
Mark Hook, who runs a guesthouse near Ullswater, said water was lapping at his door.
He said: "It's quite a scary thought really... once yes, twice worrying, but three times is not good at all.
"When you've just cleaned everything up and are getting ready for decorating or carpet relaying, you're thinking 'should I do this? should I hold on?'."
A fundraising appeal for victims of the flooding launched in the wake of Storm Desmond has increased its target to £6m.
The Cumbria Community Foundation said it had raised almost £3.5m so far, and the higher amount reflected "a growing sense of the true scale of the need".
Organisers said priority would be given to individuals and families suffering financial hardship, and community relief and rebuilding projects.
Meanwhile, two flood warnings remain in place across Cumbria.
Live flood warnings from the Environment Agency and the Scottish Environment Protection Agency.
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