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Forecast Products Users'Meeting, 15-17 June 2005 HB 1
Users’ meeting SummaryPerformance of the Forecasting System (1)Main (deterministic) model
- Outstanding performance last winter over NH
- Excellent results and consistent upward trend for Europe as measured by ANC Z500hPa
- The average lead over an ensemble of centres has been maintained, as confirmed by ‘gain’ statistics, however, some centres have also progressed significantly
EPS- Performance continues to improve, recent changes to the
forecasting system had a positive impact
- Upward trends in performance are reflected in RPSS scores for Z500 and in skill scores for weather parameters
Forecast Products Users'Meeting, 15-17 June 2005 HB 2
Users’ meeting SummaryPerformance of the Forecasting System (2)Severe weather event prediction
- Tropical cyclone forecasts have improved significantly last year, providing generally good guidance
Core pressure is underestimated, better in higher resolution
Bias towards slow movement
Delineating the TC in the analysis is important, bogussing should be re-
considered
Some overconfidence in strike probabilities
- First steps towards verification of the EFI
Station verification of ‘extreme’ precipitation events over Europe using
the EUMETNET/ECSN Climate Atlas
Self-calibrating properties of the EFI provide improved guidance over
‘raw’ model probabilities
- Example of successful indication of freak waves in analysis and forecast
Forecast Products Users'Meeting, 15-17 June 2005 HB 3
Users’ meeting SummaryPerformance of the Forecasting System (3)Weather parameters
- One day gain per decade in predictive skill of moderate amounts of precipitation
- Same improvements cannot be demonstrated for large amounts- Up-scaled precipitation analysis based on high resolution observing
network is used for verification in delayed mode Provides more reliable and robust results obtained at the
scale of the model Reduced frequency bias in particular for small amounts
compared with verification results obtained when using scattered SYNOP network
- Problems with treatment of low level clouds during persistent inversions over central Europe in winter, improved boundary layer cloud scheme was introduced in April 2005 and will help alleviate these deficiencies
- Some evidence of positive trend in T2m forecasts over North America and parts of Europe
- Episodes of strong low level inversions and extreme cold conditions over Europe in February contribute to larger errors
Forecast Products Users'Meeting, 15-17 June 2005 HB 4
Users’ meeting SummaryPerformance of the Forecasting System (4)Monthly forecasts
- Operational since October 2004, dissemination was added spring 2005
- ROC area score indicates skill in T2m over persistence for days 12-18, to a lesser extent for days 19-32
- Good predictions of transition between flow regimes last winter
- Outer quintiles for T2m are skilful
- Meteo France finds moderate skill in T2m forecasts for week 3 over France
Forecast Products Users'Meeting, 15-17 June 2005 HB 5
Users’ meeting SummaryPerformance of the Forecasting System (5)Seasonal forecasts
- Predictions of the monsoon precipitation for JJA 2004 verified well
- Good representation of ocean currents in tropical Pacific
- Over the West Pacific basin the forecast predicted successfully higher tropical storm activity than the climatology; over the Atlantic the forecast has not been as good
- Dry conditions over the Iberian Peninsula were consistently predicted since November 2004
- Potential benefit from multi-model system: reduced rms error and improved correlation, eg for NINO3 SST forecasts
Forecast Products Users'Meeting, 15-17 June 2005 HB 6
Users’ meeting SummaryDevelopment of the Forecasting System(1)
Cy29r2 end June, to include- 3-hourly EPS post-processing to 132 hours
- Near-real-time hindcast runs to create model climate for EFI
Plans to implement higher resolution forecasting system in autumn 2005 (T799L91/T399L62)- First test data in Mars end June
- E-suite data in Mars from mid-July
- Test dissemination by arrangement early September
- Information on web
Unified system (VAREPS) with extension to 15 days end 2005
VAREPS to merge with monthly forecast early 2006Seasonal forecast system3
Forecast Products Users'Meeting, 15-17 June 2005 HB 7
Users’ meeting SummaryDevelopment of the Forecasting System(2)Product development
- Extended EPSgrams for Unified System
- Global and regional multi parameter EFI maps
- Prototypes of combined multi-model seasonal products
- New monthly forecast products, eg synoptic view of temperature and flow anomalies
Additional archiving from monthly forecasting system- Weekly anomalies
- Terciles
Additional verification from monthly system on webFields from up-scaled precipitation data to be in MARS
Forecast Products Users'Meeting, 15-17 June 2005 HB 8
Users’ meeting SummaryUse and evaluation in Member States (1)
Users report on a wide range of applications and usage of medium and extended range products- Early delivery system improved the usefulness of the forecasts,
also in the early stages of the forecast range
- Presentation of probabilistic forecast information to the public
On the web (DK, NL,…), EPS spread expressed as range, probabilities used for exceeding thresholds
Weather scenarios are presented for days 7-9 (DK) Newspaper (S,..) On TV (NL, S..)
- Several case studies of successful severe weather event forecasts (HUN, DWD, N,…)
- Influence of weather data (T, precipitation, wind) on energy markets, probabilistic information is used to create level of confidence
- Weather risk applications
Forecast Products Users'Meeting, 15-17 June 2005 HB 9
Users’ meeting SummaryUse and evaluation in Member States (2)
Limited area ensemble prediction (COSMO-LEPS, LAMEPS)- Encouraging results were reported from several applications
- Aiming at downscaled severe weather event prediction
- Use of LAMEPS output in Eurorisk project, storm surge model, input to hyrdological models (N)
Ensemble prediction- Ensemble mean is found useful for point forecasts
- Benefits of probabilistic forecast information was emphasized
- EFI used to alert forecasters (e-mail sent automatically (SUI))
- Probability forecasts under development for locations along the Finnish coast
- Meteo France plans to study the skill in predicting weather regimes in the monthly forecasts
- Used as input for hydrological forecasts (river discharge)
- Experimental use of new CAPE parameter (NL)
- Automatic generation of weather alarms for forecasters (NL)
Forecast Products Users'Meeting, 15-17 June 2005 HB 10
Users’ meeting SummaryUse and evaluation in Member States (3)
Other issues- IRI reported on the potential benefit of extended range
forecasts for predicting rainfall in regions epidemically affected by malaria outbreaks
- MetO reported on significant problems with the generation of convective snowfall over the North Sea in north-easterly flow in late winter 2005
- MetO further investigated the verification results for early warnings, previously experienced anomalies in the results with a maximum in skill disappear when applying verification procedures which are more in line with standard NWP procedures
- KNMI presented a web catalogue of high impact weather events, using ERA-40 as a documentary
Forecast Products Users'Meeting, 15-17 June 2005 HB 11
Users’ meeting SummaryUser requirements
Medium range forecasting system
- Provide 3-hourly post-processing from the EPS
- Consider the development and extension of suitable products to 15 days with the planned extension of the forecast range
- Develop suitable products for the unified forecast system
- Requirement for hindasts/learning sample prior to model upgrades
Forecast Products Users'Meeting, 15-17 June 2005 HB 12
Users’ meeting SummaryUser requirements (2)
Monthly forecasting system
- Increase the number of members (from currently 5) in the hindcast ensembles
- Time of the runs and the delivery should be reviewed
Multi-model seasonal forecasting system
- Develop combined and calibrated multi-model products
- Standardize the hindcast periods
- Standardize the reference periods for anomalies
- Standardized toolbox for verification is of interest
Support for time critical applications run at the Centre by Member States
Forecast Products Users'Meeting, 15-17 June 2005 HB 13
Users’ meeting SummaryUser requirements (3)
Requests for productsTimely updating of products on the web is importantExtend the range of web productsGlobal EFI products to be made available to WMO
membersCAPE parameter in future ERATimes of product delivery to be reviewed after the
implementation of the planned upgrades in 2005/early 2006