A tilted updraft (also known as a tilted storm) is a

thunderstorm A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by the presence of lightning and its acoustic effect on the Earth's atmosphere, known as thunder. Relatively weak thunderstorms are some ...

which is not vertically erect. This happens as a result of unidirectional

wind shear Wind shear (or windshear), sometimes referred to as wind gradient, is a difference in wind speed and/or direction over a relatively short distance in the atmosphere. Atmospheric wind shear is normally described as either vertical or horizont ...

, or a change in wind speed with height. In such an environment, the top of the

updraft In meteorology, an updraft is a small-scale current of rising air, often within a cloud. Overview Localized regions of warm or cool air will exhibit vertical movement. A mass of warm air will typically be less dense than the surrounding regi ...

is pushed further

downstream Downstream may refer to: * Downstream (bioprocess) * Downstream (manufacturing) * Downstream (networking) * Downstream (software development) * Downstream (petroleum industry) * Upstream and downstream (DNA), determining relative positions on DNA ...

than the lower parts as a result of stronger winds pushing the top, as it is higher in the atmosphere. Storms that occur in environments with wind shear are more likely to be severe.

References

Severe weather and convection {{climate-stub fr:Technique de Lemon#Technique