"Jet streams are fast flowing, narrow, meandering air currents found in the atmosphere of some planets, including Earth. On Earth, the main jet streams are located near the altitude of the tropopause and are westerly winds (flowing west to east)."
(Wikipedia definition)
Considering global will feature live weather, will it feature the jet streams that cross the Atlantic? They can speed up aircraft by almost 100 miles an hour, and are very important for trans Atlantic travel, so it would be important (and realistic) to feature them in global.