Step change, almost overnight, last week from ~40s F to ~70s F. MPG up from average of about 59 to 69. 10mpg, consistently, and still climbing as temperatures rise. For instance, today's ride into work and some errands was ~37 miles and I am showing 73mpg. Temp was about 5 degress wamer this morning than it has been. Why: I notice in the warm temperature, the car uses EV much more. Further, the car will go in EV all the way down to 1 bar in the battery. It will also hold EV sometimes mid way between the "eco" line and the "power" line on the hybrid system display.