The forecast you see in a trip planner became more realistic
Last week Tesla updated the user manual of their cars with an important point. Now electric cars will estimate the range on a current level of charge considering weather conditions and the elevation on route.
Such methodology should allow the trip planner to forecast the charge level to remain at the final destination and thus suggest points of charging on the way.
The updated algorithm is especially important for cold regions and regions with huge elevation. Such factors may influence a 10-15% difference between planned and real rate of discharge.