Taking the temperature outside A&E could give staff an accurate way to predict number of injuries and who will suffer them.
Experts know that extreme weather can affect A&E patient numbers.
Warwick University researchers found that even 5C falls or rises could make a difference to injury rates.
Rates for children were up to 70% higher in summer compared with winter, the Emergency Medicine Journal reported.
Many trusts plan ahead for winter, when the arrival of frost, snow and ice, as well as flu and pneumonia, is traditionally linked to busier shifts.
The study of 60,000 patients found that each 5C drop in minimum temperature during the day meant a three per cent rise in serious accidents to adults.