Lightning cessation typically occurs when a storm decays to the point of no longer producing lightning. It is indicative of a weakened updraft. This is an important event for forecasters to predict well, as event managers and other users need good guidance on when they can expect a lightning threat to be over.
LightningCast predicts the probability of lightning in the next hour, including before first-flash events in storms, and for lightning cessation. LightningCast v1 uses solely ABI inputs. This sometimes makes it difficult to discern lightning cessation, particularly when the reflective bands are not present (or strongly illuminated) and when there is thick ice present with a “smooth” look at cloud-top, which often is the case when storms decay, leaving an anvil cloud.
The animation below demonstrates LightningCast v2 (on the left) vs. LightningCast v1 (on the right). LightningCast v2 incorporates the MRMS Reflectivity -10C as a predictor at 1-km resolution. This helps the LCv2 to “see” the diminishing lightning signal sooner than in LCv1, due to a collapsing updraft and reflectivity core, which often precedes warming cloud tops in satellite imagery.
LCv2 (left) reduces lightning probabilities for the storm on the Oklahoma/Kansas border much more rapidly than LCv1 (right).
Toggling of LCv1 vs. LCv2 at 11:46 UTC helps us see the false-alarm-area reduction in south-central Kansas for LCv2. Predicting lightning cessation is one important scenario where we feel that LCv2 improves upon LCv1.
