In an internal memo – seen by ITV News – a senior consultant tells colleagues of the "incredibly challenged" position at the Leeds Teaching Hospitals Trust and warns that the worst could be yet to come.
It says the number of patients with the virus at Leeds General Infirmary and St James's Hospital could exceed 450 next week – higher than the 360 seen at the peak of the last wave a year ago.
The author of the memo begins by wishing colleagues a "happy new year". But, with almost 1,300 staff isolating because of Covid-19, she adds: "It's not proving to be a very joyful new year in terms of the number of Covid patients that are flooding into the trust."
The doctor goes on to lay bare the huge challenges facing hospital staff:
An increase in Covid patients from 48 on Christmas Eve to 254 within a little over a week
An instruction to stand down all planned surgery except where it is "immediately life, limb or sight saving"
Medical consultants facing an "awful position", with an "unmanageable" workload
A call for specialist doctors to "step out of our comfort zone" to support general medical practitioners.
The memo adds: "I can't stress enough how much pressure our medical colleagues are under – the situation is dire."
Dr Hannah Barham-Brown, of the British Medical Association, told ITV News: "The worst is yet to come and I'm quite scared of the situation we already have.
"Across health and social care we are in a dire situation. It's the worst I've ever seen it."
Today, the trust's chief medical officer Dr Phil Wood said its hospitals had seen a "significant increase" in the number of Covid-19 patients since Christmas.
He added: "We are experiencing increased numbers of staff who are off with Covid or Covid-related illness, so that puts our hospitals under strain over and above what we might normally expect."
But he urged people not to stay away from hospital if they needed treatment.
Dr Phil Wood speaks to ITV News reporter Jon Hill
What does the official data show?
There is a lag in the government's published statistics on hospital admissions, which only go up to 28 December.
On that day there were 95 Covid-19 patients in the hospitals run by Leeds Teaching Hospitals Trust, 11 of them admitted that day. There were 11 on ventilation on the same day.
During December 27 people died within 28 days of a positive test.