| In the scope of the European project Hydroptimet, INTERREG
IIIB-MEDOCC programme, limited area model (LAM) intercomparison of
intense events that produced many damages to people and territory
is performed. As the comparison is limited to single case studies,
the work is not meant to provide a measure of the different
models' skill, but to identify the key model factors useful to
give a good forecast on such a kind of meteorological phenomena.
This work focuses on the Spanish flash-flood event, also known as
"Montserrat-2000" event.
The study is performed using forecast data from seven operational
LAMs, placed at partners' disposal via the Hydroptimet ftp site,
and observed data from Catalonia rain gauge network. To improve the
event analysis, satellite rainfall estimates have been also
considered.
For statistical evaluation of quantitative precipitation forecasts
(QPFs), several non-parametric skill scores based on contingency
tables have been used. Furthermore, for each model run it has been
possible to identify Catalonia regions affected by misses and
false alarms using contingency table elements. Moreover, the
standard "eyeball" analysis of forecast and observed
precipitation fields has been supported by the use of a
state-of-the-art diagnostic method, the contiguous rain area (CRA)
analysis. This method allows to quantify the spatial shift
forecast error and to identify the error sources that affected
each model forecasts.
High-resolution modelling and domain size seem to have a key role
for providing a skillful forecast. Further work is needed to
support this statement, including verification using a wider
observational data set. |