Also known as “explosive cyclogenesis
,” this term refers to a rapidly deepening extratropical
with a central pressure
that falls on the average of at least 1 hPa h−1
for 24 h, after applying an adjustment to a latitude
of 60° using the following equation: r
), where r
is the observed pressure fall (hPa h−1
) and ϕ
is the cyclone’s latitude. This adjustment accounts for variations in the geostrophic wind
speed induced by equivalent pressure gradients
at different latitudes. Consequently, it requires a larger pressure drop to qualify as a bomb cyclone at higher latitudes compared to lower latitudes.
This predominantly maritime, cold-season event is usually found approximately 750 km downstream
from a mobile 500-hPa trough
, within or poleward of the maximum westerlies
, and within or ahead of the planetary-scale troughs.
Sanders, F., and J. R. Gyakum, 1980: Synoptic-dynamic climatology of the “bomb”. Mon. Wea. Rev., 108, 1589–1606, https://doi.org/10.1175/1520-0493(1980)108<1589:SDCOT>2.0.CO;2.
Term edited 3 July 2023.
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