ESS5
Prof.
Jin-Yi Yu
–Graupel are ice crystals that undergo extensive riming
•Lose six sided shape
and smooth out
•Either falls to the
ground or provides a nucleus for hail
–Hail
forms as concentric layers of ice build around graupel
•Formed as graupel is
carried aloft in updrafts
•At high altitudes,
water accreting to graupel freezes, forming a layer
•Hail falls but is eventually carried aloft again by an updraft
where the process repeats
•The ultimate size of
the hailstone is determined by the intensity of the updraft.
•Great Plains = highest
frequency of hail events
Graupel and Hail