Tropopause

The tropopause is the boundary between the troposphere and the stratosphere, where an abrupt change in lapse rate usually occurs. It is defined as the lowest level at which the lapse rate decreases to 2 °C/km or less, provided that the average lapse rate between this level and all higher levels within 2 km does not exceed 2 °C/km.
Definition by the ▸WMO (World Meteorological Organization).

The following charts show the temperature and the geopotential height of the tropopause for today and the next few days.

Charts for analysis and forecast

Geopotential height

Temperature