Abstract
Mesoscale Convective Systems (MCS) are common over Europe and can
produce severe weather, including extreme precipitation, which can lead
to flash floods.
The few studies analyzing the climatological characteristics of MCS over
Europe are either based on only few years of data or focus on limited
sub-areas.
Using the recent Integrated Multi-satellitE Retrievals for Global
Precipitation Measurement (IMERG) satellite precipitation climatology,
we identify and track MCS for 16 years over Europe.
We devise a spatial filter and track cells according to the overlap of
filtered rain patches between consecutive time steps.
By fitting an ellipse to these patches, we determine their overall shape
and orientation.
To distinguish convective rain patches we condition on lightning data,
thus reducing potential identification errors.
We analyze this new European MCS climatology to characterize MCS
rainfall properties:
MCS overall occur most frequently over the Mediterranean and Atlantic
during fall and winter, whereas during summer, they concentrate over the
continent.
Typically, more than half of seasonal precipitation can be attributed to
MCS, and
their contribution to extreme precipitation is even greater, often
exceeding 70\%.
MCS over the continent display a clear diurnal cycle peaking during the
afternoon, and some continental areas even show a second, nocturnal
peak.
The MCS diurnal cycle for coastal and oceanic regions is more
variable.
Selecting sub-areas, we find that the spatio-temporal distribution of
MCS precipitation throughout the year can be well explained by the
spatio-temporal distribution of specific environmental variables, namely
(sea) surface temperature, fronts occurrence and convective instability.