This is from some service data.
"Note: The transmission fluid level should be checked at normal operating temperatures, 66°C - 77°C (150°F - 170°F), on a level surface. The normal operating temperature can be reached after approximately 32 km (20 miles) of driving. However, you can check the fluid level without driving if the outside temperature is above 10°C (50°F). When the vehicle has not been driven, and the outside is above 10°C (50°F), the fluid level should be between the holes on the indicator. If the transmission fluid is to be checked when the fluid is at room temperature, the fluid level indicator could indicate that fluid should be added if the indicator is misread. If fluid is added at this time, an overfill condition could result when the vehicle reaches operating temperature of 66°C - 77°C (150°F - 170°F)."