Garmin G1000:Socata Pilot's Manual page 337

Along squall lines (multiple cells or clusters of cells in a line) individual cells may be in different stages
of development. Areas between closely spaced, intense targets may contain developing clouds not having
enough moisture to produce a return. However, these areas could have strong updrafts or downdrafts.
Targets showing wide areas of green are generally precipitation without severe turbulence.
Irregularities in the target return may also indicate turbulence, appearing as hooks, fingers, or scalloped
edges. These irregularities may be present in green areas with no yellow, red, or magenta areas and should
be treated as highly dangerous areas. Avoid these areas as if they are red or magenta.
Thunderstorm development is rapid. A course may become blocked within a short time. When displaying
shorter ranges, periodically select a longer range to see if problems are developing further out. That can
help prevent getting trapped in a blind alley or an area that is closed at one end by convective weather.
190-00709-00 Rev. A
Steep Gradient
Figure 6-42 Cell Irregularities
Figure 6-43 The Blind Alley - Horizontal Scan
Garmin G1000 Pilot's Guide for the Socata TBM 850
Squall Line
Hook or Finger Scalloped Edge
HAZARD AVOIDANCE
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