Introduction
This work illustrates the operational performance of LAMBO (Limited Area
Model Bologna) in forecasting the intense and continuous precipitation,
which caused the flood event that occurred on the 5th and 6th of November
1994. As described in the previous paper of this Newsletter(Buzzi et al.
1995, hereafter referred as BA95), precipitation occurred principally on
the 5th due to the persistent impinging of a low-level southerly flow,
which moistened during the passage over the sea and was blocked by the
Alpine chain. LAMBO, running operationally at SMR/ER, is a grid-point
primitive equation model mainly based on the 1989 version of the Limited
Area Model operational at the National Meteorological Centre of Washington
(NMC). The SMR operational chain consists of two runs of LAMBO; the first
run is performed at about 40 km horizontal resolution and the second one at
about 20 km. Initial Conditions and Boundary Conditions are taken from
ECMWF (European Centre for Medium Range Weather Forecast) operational
objective initialized analyses and forecasts. All the operational
numerical integrations are performed on a CRA Y C94 machine of the CINECA
computer centre (University Computer centre) in Bologna. The two
operational runs at different horizontal resolutions are compared with
observations, and they show a generally good performance of the model with
a noticeable impact of the horizontal resolution, in particular with regard
to the representation of precipitation maxima. Some of the precipitation
data and the meteorological description of the situation are not included
in this paper, and the reader is referred to the aforementioned BA95.
Description of the model
The meteorological limited area model LAMBO operational at SMR/ER is a
grid-point primitive equation model based upon a version dated 1989 of the
ETA (UB/NMC) model (now operational at the National Meteorological Centre
of Washington, NOAA-NMC, see Mesingeret al., 1988; Black, 1988; Janijc,
1990; Lazic and Telenta 1990). LAMBO has recently been upgraded in some
parts of the physical parameterization schemes from the new version of the
NMC code, and with a new radiation code from Meteo-France (Ritterand
Geleyn, 1992). Since the radiation code has not yet been modified to allow
for the ETA vertical coordinate, the operational version of the model is at
the moment
MAP Newsletter. October '00