Evaluating Extended Range Convection Products

AWT participants had the opportunity to look at new extended range convective forecast products this week with the goal of exploring various ways of depicting hazard information to support strategic planning for the next day and beyond. Evaluations included examining both automated and user generated forecast products.

Participants generated convective coverage forecasts over 6 hr windows (09-15z, 15-21z, 21-03z, 03-09z) during the Day 2 period. These forecasts depict areas of high confidence in convective coverage areas in the same manner as current standard TCF forecasts, communicating threat areas for strategic planning to focus on for the Day 2 period. Participants have provided positive feedback for these forecast products, indicating that they have potential to provide useful information for planning at extended ranges. During the week, emphasis has been placed on the importance of consistent forecast messaging between a Day 2 and a Day 1 product.

Participant generated convective coverage forecast graphic

In terms of automated guidance, participants evaluated two automated products currently produced at the Aviation Weather Center (AWC) for extended range convection. Comparisons were made between the Extended Convective Forecast Product (ECFP), which shows convective probabilities over a 6 hour window, and the Extended Traffic Flow Management Convective Forecast (eTCF), which displays a convective coverage forecast at 2 hour snapshots. Participants have found that the eTCF provided more useful guidance in the Day 2 period compared to the ECFP, as the inclusion of convection allowing model (CAM) guidance in the eTCF allows for greater detail in the evolution and timing of convection.

Comparison of operational and variant eTCF forecasts (upper left, upper right, lower left) with observations (lower right)

Additionally, participants evaluated two experimental variants of the operational eTCF, which is created through a blend of models which include convection parameterization and CAM guidance. Both variants were comprised of a blend of solely CAM guidance and have performed better than the operational eTCF in both subjective and objective evaluations. The improved performance of the variants can be attributed to the ability of the CAM guidance to better forecast the evolution and timing of convective processes. Based on these results, a potential upgrade to the operational eTCF will be explored in the near future.