1. Convective Forecast Verification Operational Impact Assessment
Jennifer Mahoney, Mike Kay, Sean Madine, Joan Hart
Forecast Systems Laboratory
Barbara Brown
National Center for Atmospheric Research

2. Background
Verification techniques are strongly tied to the product definition and intended use of a forecast. Therefore, the verification problem becomes very difficult when the forecast is not clearly defined.
Goals:
Clarify the product definition and intended use of Collaborative Convective Forecast Product (CCFP).
Demonstrate techniques for evaluating the operational impact of CCFP.

3. Verification of CCFP Product Definition (Meteorological) – Use –
A region spanning at least 3,000 sq. miles and containing at a minimum, echoes of at least 40 dbZ composite reflectivity, covering at least 25% of the CCFP region, with tops at least 25,000 ft.
Use –
CCFP is a strategic tool used for developing a plan or framework for managing the impact of convective weather on the air traffic flow system (e.g., Baseball).
Operational impact –
CCFP region contains the convection as well as a measure of the possible impact of the convection on the flow of air traffic.

5. Convective Constrained Area (CCA)
Raw Observations
30 June 2004
CCA-10
CCA-20

6. Operational Impact Coverage Field
Flight handbook rules
Raw observations
CCFP product
definition
Operational Impact
Coverage Field -
Guidance for a CCFP
30 June 2004

7. Future Work
Regionalize the operational impact coverage field by region, sector, and time of day.
Incorporate echo top information into the convective constrained area.
Evaluate flight track data to quantify the impact of convection on the flow of air traffic.

8. Conclusions
CCFP should only be used as a tool for establishing a plan for managing the flow of air traffic.
Verification methods can be developed for CCFP that incorporate the operational impact of convective weather on the flow of air traffic.
There is no right answer. There are many ways to evaluate a forecast. All methods tell you something about the quality and usefulness of the forecast.

9. Acknowledgments Thanks to
Tom Fahey
Fred Johnson
Jack May
Dave Rodenhuis
for numerous discussions and valuable in site.