Mid Yorkshire Hospitals Trust has teamed up with other NHS Organisations and local authorities to draw up its Winter Plan for safe patient care.
The trust, which runs Pinderfields, Pontefract and Dewsbury hospitals, said cold conditions were expected to be caused by the El Nino weather phenomenon this winter.
The Winter Plan report said: “For the first time since 2009, computer simulations are suggesting that an El Nino event is likely in the second half of 2015.
“Initial reports from the Met Office are predicting temperatures to be colder than the seasonal average throughout the whole of winter, with accompanied storms in December and January and a higher chance of a deep snowfall in late January.”
The trust was working to avoid unnecessary hospital admissions during the winter to ease demand on A&E departments.
The report said: “No patient should have to attend A&E as a walk in because they have been unable to secure an urgent appointment with a GP.
“Rapid Assessment and treatment should be in place to support patients in A&E and acute medical units to receive safer and more appropriate care as they are reviewed by senior doctors early on.”
Measures include an increased presence from social work staff to help hospital patients return home.
The report said: “During the winter period there will be increased hours for social work in hospital over seven days, including all Bank Holidays.”
The trust was also aiming to vaccinate 75 per cent of staff against flu. Almost 20 per cent had been vaccinated so far.
The report said: “In order to minimise the impact of the seasonal flu, a robust influenza immunisation programme has been developed for all our staff.”
The report also said staff holidays would not be agreed until wards were fully staffed.
It said: “This should take into account sickness absence and maternity leave and vacancies.”