Using temperature layered VIL as automated lightning warning guidance

The 45th Weather Squadron (45 WS) is the U.S. Air Force unit that provides weather support to America's space program at Cape Canaveral Air Force Station (CCAFS) and NASA Kennedy Space Center (KSC). CCAFS/KSC is located in east central Florida, at one end of °¥Lightning Alley' in the U.S. One of the many duties of 45 WS is to issue lightning watches and warnings for 14 circles of 5 nmi radius centered on a key operational locations where outdoor work is performed. The 45 WS has developed many techniques for lightning forecasting at CCAFS/KSC, most of which have been reported previously. However, one technique has not been reported. This technique uses radar vertically Integrated Liquid (VIL) above 0„aC as an automated lightning warning guidance product. If the temperature layered VIL meets or exceeds an empirically tuned threshold, then lightning is likely to initiate in that area. This empirical threshold is tuned for the occurrence of any lightning, including lightning aloft as opposed to just cloud-to-ground lightning, to match the 45 WS policy on lightning watches and warnings. A graphical display highlights the areas that meet or exceeds the threshold and is updated each volume scan as guidance to the forecaster on where the initiation of lightning is likely in the near future.

This paper will review the previously reported 45 WS techniques for lightning forecasting and then cover the temperature layered VIL technique in more detail. Finally, possible ways to improve the temperature layered VIL technique will be discussed.