1. Linking operational activities and research
Aida Diongue-Niang
ANACIM/Senegal Met. Service
African THORPEX Regional Committee co-chair
ICSC-9, Geneve, September 2011

2. Weather Forecasting: Forcaster’s tasks
observations
Model analyses
Analysis of the current meteorological situation
Examination of the Future Evolution of the atmosphere and choice of the most likely scenario
one or more Deterministic Models forecasts: poor’s man ensemble
Ensemble prediction Systems, single or multi-model
Experience
Monitoring and Updating
Description of the evolution of the atmosphere and the expected weather
Distribution of products to end-users
Decision on issuing warning in case of severe weather
Verification /Validation

3. Advances in Africa
African National Met. Services have free access to some global model products through Eumetcast (e.g. ECMWF, UK) or Internet (e.g. GFS) to facilitate operational weather forecasting.
Forecasters’ weather stations for receiving, processing and display (e.g. Messir. Com, MSG, Synegy)
Regional and local modelling are preformed in few NMS to take more account their regional/local chracteristics, provide diagnostics needed, for applications (e.g Marine, air quality)
Pioneers: South Africa and then Morocco
Less than six countries running operational weather models

4. Challenges of Op. Weather Forecasting in Africa
Mainly related to:
Poor observing network,
Model performance,
Gap in modelling and model use,
Lack of training to catch-up with new tools (e.g GPS, EPS) and to update knowledge (interactions research- operational)
Poor Technical environment
Lack of documentation (e.g Forecaster’s handbook, systematic reports) and systematic verification

5. Challenges related to observing systems to construct initial conditions: surface observations

6. Statistics for synop reports

7. Challenges related to observing systems to construct initial conditions: upper-air

8. Challenges in Weather Forecasting: Precipitation
Measures of Forecast Skill
Anomaly Correlation Coefficient
(over European Sector)
500 hPa Heights
Precipitation
Potential Vorticity
ECMWF

9. ACC Asian Monsoon Rainfall
Monotonic improvement in skill
12UTC deterministic forecasts are used. Approximately 180 SYNOP stations are used each day

10. ACC North African Monsoon Rainfall
Little or no skill
12UTC deterministic forecasts are used. Approximately 20 SYNOP stations are used each day

11. Trends in 1-SEEPS (larger is better) : a skill based on contingency tables and precipitation categories defined by the local climatological probabilities
T. Haiden

12. Model background errors in NWP and Climate models over Africa (JJA)‏
Met Office, UK
Climate 20Year:
HadGEM2 - GPCP
NWP :
Day 1 - GPCP
GPCP:
NWP 2005: Day 1 - GPCP
NWP 1992: Day 1 - GPCP
Just to illustrate the strong link between NWP and climate this shows the day 1 error from NWP forecasts over a 15 year period and the 20 year
© Crown copyright Met Office 12

13. Model errors in “dynamic” fields: AEJ in the framework of JET2000
hPa s N
120h Forecast

14. ICSC-9, Geneve, 21-22 September 2011
Summary
High-impact weather: a major thread for Africa
Predicting High-impact weather particularly challenging in Africa
Need to assess predictive skill of HIW and model ability to predict HIW in order to determine systematic errors and model limits
Operational community invited to do systematic report of HIW events and basic verification of the forecast for feedback to research community and NWP centres
Reseaerch community invited to do more analysis and modelling studies based on selected cases by operational community
NWP centres invited to improve models globally
ICSC-9, Geneve, September 2011

15. Template for reporting HIW basis SWFDP templates
First, define threshold
Example of template to discuss
ICSC-9, Geneve, September 2011