2020 crv hybrid.

Does cold weather drop mpg. I noticed it seemed to on my hyundai.
for months the mpg on screen didn't move at all. Then, in this cold it dropped to a low of 31 from 40! Not only that but I've been able to watch mpg rise and lower in real time.

 

yes cold weather will drop milage as much as 25 % oil gets thicker, if you drive through slosh this will cause the engine to work harder consuming more fuel.

 

If you spend any time warming up the car when it is frigid outside then the gauge could read lower for MPG.
Also, engine would spend more energy towards heat if you are using electrical heaters such as heated seats??
On top of that, when air in take is not at optimal temperatures then the efficiency of the engine drops. Too hot or too cold.