Current plans for NHS services this winter "lack sufficient energy", MPs on the Commons' health committee have warned.
Their report out today said it was "mindful of the pressures that will build this winter" as accident and emergency resources struggle to cope.
A&E departments are already acting as a 'safety valve' by picking up the slack from other struggling care services.
MPs found hospitals did not fully understand the challenges facing A&E or, astonishingly, who is responsible for managing them.
Now the fear is that the urgent care boards supposed to be managing the system do not come up with sufficiently robust plans for their areas before winter arrives.
"We were not convinced that the plans presented to us represented an adequate response to the challenges the system faces," committee chair Stephen Dorrell said.
“We were concerned that witnesses disagreed about the nature of demand for urgent and emergency care.
"The system is 'flying blind' without adequate information about the nature of the demand being placed upon it."
MPs called on ministers to seek greater clarity from NHS England about its plans for urgent care boards.
The committee wants the Department for Health to ensure that they, or health and wellbeing boards, are required to account for an urgent care plan for their area by September 30th this year at the latest.
MPs said it was "extraordinary" that consultant coverage is only guaranteed for 16 hours a day in just 17% of designated A&E departments.
The problem was even worse at weekends, when recent reports have revealed a higher death rate in the NHS.
"We know that early assessment by a senior clinician can improve outcomes and accelerate a patient's progress through hospital, but for this to happen there must be sufficient numbers of senior staff in the emergency department," Dorrell added.
Labour said the report showed the blame for the problem rested firmly with the government.
"This A&E crisis has developed on David Cameron's watch," shadow health secretary Andy Burnham said.
"The time for excuses and blame-shifting is over. Cameron must act on this report without delay if this coming winter is not to turn out even worse than the last."