![](\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2023\/02\/230224_goes18_visible_infrared_glmFlashExtentDensity_SoCal_tornado_warning_anim.gif\")
<\/a>GOES-18 “Red” Visible (0.64 \u00b5m) and “Clean” Infrared Window (10.3 \u00b5m) images, with\/without an overlay of GLM Flash Extent Density [click to play animated GIF | MP4<\/strong><\/a>]<\/p><\/div>1-minute Mesoscale Domain Sector GOES-18 (GOES-West) <\/em>“Red” Visible (0.64 \u00b5m<\/strong><\/a>) and “Clean” Infrared Window (10.3 \u00b5m<\/strong><\/a>) images (above)<\/strong><\/em>, with and without an overlay of GLM<\/strong><\/a> Flash Extent Density, showed convection moving onshore in Southern California during the late morning hours on 24 February 2023<\/strong><\/a> — which prompted NWS Los Angeles<\/strong><\/a> to issue a Tornado Warning<\/strong><\/a> at 1807 UTC. There was a notable lightning jump that began at 1803 UTC, 4 minutes prior to the issuance of the Tornado Warning.<\/p>\n GOES-18 “Red” Visible (0.64 \u00b5m) images, with an overlay of GLM Flash Extent Density and contours of LightningCast Probability [click to play animated GIF | MP4<\/strong><\/a>]<\/p><\/div>1-minute GOES-18 Visible images (above)<\/strong><\/em> include contours of LightningCast<\/strong><\/a> Probability. Cursor-sampled maximum values of LightningCast Probability within each contour (below)<\/strong><\/em> indicated that while the offshore probability values were fairly low (ranging from 12% to 22%), they did begin to appear as early as 1748 UTC<\/strong><\/a> (19 minutes prior to the Tornado Warning) — and probability values increased to a more modest 33% at 1815 UTC<\/strong><\/a> as the tornado-warned storm moved farther inland (and the aforementioned lightning jump was still underway).<\/p>\n<\/a>