"This remarkably mild winter follows an exceptionally hot 2006 autumn, which has not been seen before in the 1950-2006 period and without doubt even for several centuries," Meteo France said in a statement.
It added that northeast France was especially mild, with temperatures almost 3 C above normal in the three winter months. It said the outlook was for a hotter-than-normal spring.
A government committee held a monthly meeting on the water situation in France on Thursday and urged users, especially farmers, to be careful, saying rainfall between September and February was slightly lower-than-average.
"The water situation is worrying and one must remain attentive," Environment Minister Nelly Olin said, adding that water restrictions looked almost certain in some areas.
(Additional reporting by Paule Bonjean)