Horizontal convective rolls, also known as horizontal roll vortices or cloud streets, are long rolls of counter-rotating air that are oriented approximately parallel to the ground in the planetary boundary layer.

Horizontal rolls are counter-rotating vortex rolls that are nearly aligned with the mean wind of the Planetary Boundary Layer (PBL). They can be caused by convection in the presence of a moderate wind and/or dynamic inflection point instabilities in the mean wind profile.

Apr 1, 1997 · The environmental conditions necessary for sustaining rolls and for influencing the aspect ratio, ratio of roll wavelength to convective boundary layer (CBL) depth, and orientation are examined.

Cloud streets are technically called horizontal convective rolls. Convection rolls and the formation of cloud streets. Image via NOAA. Cloud streets are most readily seen in satellite photography, though they can be viewed from the ground too. The U.S. National Aeronautics and Space

representing roll orientation • Large L x/L y means rolls parallel with the vertical shear vector (longitudinal rolls). Small L x/L y means rolls oriented perpendicular to shear (transverse rolls) • Vertical axis (labeled at right) is amplification rate for various roll orientations More…

Jan 6, 2024 · Cloud streets are long rows of cumulus clouds that are oriented parallel to the direction of the wind. Their technical name, more specifically, is horizontal convective rolls. As a matter of...

Mar 31, 2024 · (Also known as horizontal roll vortices, boundary layer rolls.) Counter- rotating horizontal vortices that commonly occur within the convective boundary layer; their major axes are aligned with the mean boundary layer wind-shear vector.

When the buoyancy flux reached a critical value of 35–50 W m22, the first form of boundary layer convection resolved by radar was rolls. It was noted that two-dimensional convective rolls can evolve in a convective boundary layer in the absence of significant wind speed and shear.

Apr 9, 2021 · Horizontal convective rolls (HCRs) and cellular convection (cells) have been a topic of study since Woodcock (1940) explored the flight patterns of herring gulls in the cold season off the coast of Massachusetts.

Apr 1, 1997 · Data from the Convection and Precipitation/Electrification (CaPE) project, as well as results from numerical simulations, are used to study horizontal convective rolls.