Jet Stream 250 mb isotach Main Upper Tropospheric Jets Closely Associated with the Tropopause Tropopause Tropopause Height http://www.atmos.washington.ed u/~hakim/tropo/tropo.html Subtropical Jet Stream Subtropical Jet Stream Often Associated with a cloud band • http://itg1.meteor.wisc.edu/wxwise/AckermanKnox/chap7/subtropical_jet.html Jet Stream’s Relationship to Temperature Can Be Shown through Thermal Wind Arguments 250 mb isotach 1000-500 mb thickness-large thickness gradient and thus thermal wind near jet core Or alternatively… The Jet Stream Recall the horizontal temperature effects on the pressure: 500 mb 700 mb 850 mb Warm Cold Psurface The Jet Stream Consider the balance of forces at each level: Co PGF 500 mb 700 mb 850 mb Warm Cold Ps There are a variety of jet stream configurations that are wellknown