Review of yesterday's event... an EWP perspective

24-hour UWCI nowcasts (top left), overshooting top (top right) and thermal couplet detections (bottom left), and SPC storm reports (bottom right) for 17 June 2010.
Today we discussed yesterday's event over ND/MN/IA and I wanted to mention a few things we discussed with the forecasters regarding the performance of the UWCI and OTTC products leading up to and during the event. We showed the forecasters the 24-hour accumulations of UWCI, cloud-top cooling, overshooting top and thermal couplet detections with regards to severe reports from the SPC (see images above), as well as their own experiences. Forecasters did notice that cloud-top cooling was occurring on southern edge, but it was already ongoing on radar. The first UWCI signals were seen at 1855 UTC with the convection that was developing over ND and MN. The first overshooting top was detected at 1915 UTC over northern MN. These occurred just prior to beginning operations in the HWT, so it is hard to determine the CI lead times for this event given that we did not see the first detections of CI. I reiterated that we are hoping to expand the experiment in the future years by having overlapping shifts that would provide additional time to evaluate GOES-R Proving Ground products in a nowcasting perspective, which is what they are meant for originally. Forecasters did not see any thermal couplets in real-time, but did notice a few overshooting tops, especially when they began. However, they mentioned that the storms seem more low topped in nature and this may have hindered the products ability to detect these features. They were honest with me in saying that as soon as they moved into warning operations they turned the GOES-R stuff off because they did not feel it provided them with additional warning information and needed the window space for their traditional radar products.

Jordan Gerth did show the forecasters an AVHRR image that demonstrated similar to what GOES-R would see regarding overshooting tops and thermal couplets and noted that the detection efficiency would be much better. The forecasters were impressed with this and agreed that the products would perform much better in the future and appreciated us showing them the products now. The forecasters also did note that in the case of a line forming upstream from main convective area, convective initiation being detected in the line behind would help prevent getting tunnel vision and increase their situational awareness.