Tunisian National Institute
of Meteorology
ALADIN Forecasters Meeting
Plan
Introduction
Experiences
- Missed situation by Aladin model
- Well-forcasted situation by Aladin
Challenges
Expectations
Introduction
- Properties of weather in Tunisia
- Availables models
Properties of weather in Tunisia
 The classic disturbances are North-West
ones : a core of lower geopotential field is formed
on Greenland, advance towards the British Isles
and France. Arriving on the Mediterranean and
associated with the Gene’s Golf of or Lyon’s Gulf
depression, the minimum advances to Tunisia
while absorbing moisture from the sea.
 Theses situations caused rains on northern
and central Tunisia locally.
Models availables
ARPEGE model
 There
are three versions of ARPEGE model
which are availables on SYNERGIE station.
 The most usable one is the model which runs
with a resolution of 50 kilometers.
 It offers many parameters than others models
which are available on SYNERGIE station.
ARPEGE’S TOOLS on SYNERGIE
station
ALADIN TUNISIA
 This
model has been declared operational since
2004.
 The model runs with a resolution of 12.5
kilometers.
 It offers many parameters than others models
which are available on SYNERGIE station.
The interface of ALADIN model
ALADIN’S TOOLS on SYNERGIE
station
Experiences
Missed situation by Aladin : The case of
19/05/2014
-
5 death in Kairouan
-
45 mm in 3 hours
-
Wind gusts (104 km/h)
- Hail in Mahdia and
Mounastir
Source of picture : http://tn.webradar.me/
ARPEGE model outputs provided for 15 h
Sattellite picture taken at 15h UT
Informations provided by ALADIN
and ARPEGE Model
The cumulative rainfall provided by the two models
 We can note that the two models were unable
to predict the best localisation for the intensive
rains
 also, they were unables to predict the exact
quantities for the rains
 On southern Tunisia we had just stored 2 mm
in Remeda, for the others places there are praticly
no precipitations.
Well-forcasted situation by Aladin
19/09/2013
- disruptions in traffic
- water infiltration in homes,
commercial buildings and
public facilities
- 91 mm was stored in sfax
Source : http://directinfo.webmanagercenter.com/
ARPEGE model outputs provided for 12 h
Sattellite picture taken at 16h UT
Informations provided by ALADIN
and ARPEGE Model
The cumulative rainfall provided by the two models
 We can note that Aladin model was better than
ARPEGE in point of view localisation and
quantification for the intensive rains
 On northern Tunisia we had stored quantities of
rain which were not forcasted by two models
 Generally, in convective situations, ALADIN
model is not so bad. But in situations of frontal
thunderstorms, it can find big problems
CHALLENGES
We are in the obligations to work with praticly 3
models :
- ARPEGE to make short-term forecasts.
- ALADIN to neat and define our forcasts.
- ECMWF to prepare medium-term
forecasts.
EXPECTATIONS
-
-
-
To get more outputs of model to properly
analyze weather situations.
To have a meteorological radar that helps us
certainly in the immediate forecast.
To have others models with differents
properties which will allow us to better studying
meteorological situations.
Products of arome and aladin models for the
situation of 19/05/2014
Products of arome and aladin models for the
situation of 19/09/2013
Thank you for your attention