Editing Lake-effect snow (section)

=== Wind shear ===
Directional [[Wind shear|shear]] is one of the most important factors governing the development of squalls; environments with weak directional shear typically produce more intense squalls than those with higher shear levels. If directional shear between the surface and the height in the atmosphere at which the barometric pressure measures {{convert|700|mb|kPa|abbr=on}} is greater than 60°, nothing more than flurries can be expected. If the directional shear between the body of water and the vertical height at which the pressure measures {{convert|700|mb|kPa|abbr=on}} is between 30° and 60°, weak lake-effect bands are possible. In environments where the shear is less than 30°, strong, well organized bands can be expected.<ref name="Wind Shear">{{cite web |url=http://www.comet.ucar.edu/class/smfaculty/byrd/sld014.htm |title=Lake Effect Snow: Wind Shear |first=Greg |last=Byrd |date=June 3, 1998 |website=University Corporation for Atmospheric Research |url-status=dead|archive-url=https://web.archive.org/web/20080511162642/http://www.comet.ucar.edu/class/smfaculty/byrd/sld014.htm |archive-date=2008-05-11}}</ref>

Speed shear is less critical but should be relatively uniform. The wind-speed difference between the surface and vertical height at which the pressure reads {{convert|700|mb|kPa|abbr=on}} should be no greater than {{convert|40|kn|km/h}} so as to prevent the upper portions of the band from shearing off. However, assuming the surface to {{convert|700|mb|kPa|abbr=on}} winds are uniform, a faster overall velocity works to transport moisture more quickly from the water, and the band then travels much farther inland.<ref name="Wind Shear" />

[[File:Lake effect deltat chart.svg|thumb|right|Temperature difference and instability are directly related, the greater the difference, the more unstable and convective the lake-effect precipitation will be.]]