Does the number you use for average mph change drastically depending on factors such as weather? And what number do people generally use? 50 mph? Again, not sure what made me think of this, just curious I guess.
I usually use 55 mph to trip plan if my route is primarily interstate driving. You do still have to know if you could have traffic issues in a large metro area( DC, NY, LA Atlanta etc.) and add a little more time. Then sometimes all good plans will fall apart with an accident or bad weather.
I use 50 because I driver slower to save fuel. Weather ALWAYS changes things as does driving thru major metro areas. If my route is on a secondary road, I use 40. Those slowdowns as you go thru each town really take a toll on your time.
